Network Working Group Barr Hibbs
INTERNET-DRAFT (no affiliation)
Category: Standards Track Glenn Waters
Nortel Networks
November 2002
Dynamic Host Configuration Protocol (DHCP) Server MIB
<draft-ietf-dhc-server-mib-07.txt>
Saved Monday, November 04, 2002, 4:29:26 AM
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
Copyright Notice
Copyright (C) 2002, The Internet Society. All Rights Reserved.
Abstract
This memo defines an experimental portion of the Management
Information Base (MIB) for use with network management protocols in
the Internet Community. In particular, it defines objects used for
the management of Dynamic Host Configuration Protocol (DHCP) and
Bootstrap Protocol (BOOTP) servers.
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Table of Contents
1. Introduction...................................................2
2. Overview.......................................................3
2.1. Relationship to Other MIBs.................................5
2.1.1. DHCP MIB Extensions...................................5
2.1.2. Host System MIB Extensions............................5
2.1.3. DHCPv6 Server MIB Extensions..........................5
2.1.4. DHCP Client MIB Extensions............................6
2.1.5. DHCP Relay Agent MIB Extensions.......................6
2.2. Textual Conventions Introduced in this MIB.................6
2.2.1. DhcpTimeInterval......................................6
2.2.2. HardwareAddressType...................................6
2.2.3. HardwareAddressLength.................................6
2.2.4. MacAddress............................................6
2.2.5. PhysicalAddress.......................................6
2.2.6. DhcpLabel.............................................7
2.3. BOOTP and DHCP Counter Groups..............................7
2.4. BOOTP and DHCP Optional Statistics Group...................7
2.5. Response Times and ICMP Echo...............................9
3. Definitions....................................................9
4. Intellectual Property.........................................42
5. Notes.........................................................42
5.1. Issues....................................................43
5.2. Changes from Prior Drafts.................................43
6. Acknowledgements..............................................45
7. Security Considerations.......................................45
8. References....................................................46
9. Editors' Addresses............................................48
10. Full Copyright Statement.....................................49
1. Introduction
This memo was produced by the DHCP Working Group and defines a
portion of the Management Information Base (MIB) for use with network
management protocols in the Internet community. In particular, it
describes a set of extensions that DHCP and Bootstrap Protocol
(BOOTP) servers implement. Many implementations support both DHCP
and BOOTP within a single server and hence this memo describes the
MIB for both DHCP and BOOTP servers.
This memo does not cover DHCP/BOOTP client nor relay agent MIB
extensions: these are possibly the subjects of future investigation
[see discussion in section 3.1.] Also excluded from this MIB
extension in the interest of simplicity are DHCP Dynamic DNS
Updating, Failover, Authentication, and Load Balancing: these
functions and features could be subjects of future MIB extensions.
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Provision is also made for Standards-Track additions to the DHCP
Message Type (option 61.)
This memo is based on the Internet-standard Network Management
Framework as defined by documents [RFC2578, RFC2579, RFC2580].
Objects defined in this MIB allow access to and control of DHCP
Server Software. Servers MAY also provide additional management
capabilities through the use of the Applications MIB [RFC2287].
The key words "MUST," "MUST NOT," "REQUIRED," "SHALL," "SHALL NOT,"
"SHOULD," "SHOULD NOT," "RECOMMENDED," "MAY," and "OPTIONAL" in this
document are to be interpreted as described in document [RFC2119].
2. The SNMP Management Framework
The SNMP Management Framework presently consists of five major
components:
o An overall architecture, described in RFC 2571 [RFC2571].
o Mechanisms for describing and naming objects and events for the
purpose of management. The first version of this Structure of
Management Information (SMI) is called SMIv1 and described in STD
16, RFC 1155 [RFC1155], STD 16, RFC 1212 [RFC1212] and RFC 1215
[RFC1215]. The second version, called SMIv2, is described in STD
58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58,
RFC 2580 [RFC2580].
o Message protocols for transferring management information. The
first version of the SNMP message protocol is called SNMPv1 and
described in STD 15, RFC 1157 [RFC1157]. A second version of the
SNMP message protocol, which is not an Internet standards track
protocol, is called SNMPv2c and described in RFC 1901 [RFC1901]
and RFC 1906 [RFC1906]. The third version of the message
protocol is called SNMPv3 and described in RFC 1906 [RFC1906],
RFC 2572 [RFC2572] and RFC 2574 [RFC2574].
o Protocol operations for accessing management information. The
first set of protocol operations and associated PDU formats is
described in STD 15, RFC 1157 [RFC1157]. A second set of
protocol operations and associated PDU formats is described in
RFC 1905 [RFC1905].
o A set of fundamental applications described in RFC 2573 [RFC2573]
and the view-based access control mechanism described in RFC 2575
[RFC2575].
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A more detailed introduction to the current SNMP Management Framework
can be found in RFC 2570 [RFC2570].
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. Objects in the MIB are
defined using the mechanisms defined in the SMI.
This memo specifies a MIB module that is compliant to the SMIv2. A
MIB conforming to the SMIv1 can be produced through the appropriate
translations. The resulting translated MIB must be semantically
equivalent, except where objects or events are omitted because no
translation is possible (use of Counter64). Some machine readable
information in SMIv2 will be converted into textual descriptions in
SMIv1 during the translation process. However, this loss of machine
readable information is not considered to change the semantics of the
MIB.
3. Overview
In the tradition of the Simple Network Management Protocol (SNMP) the
minimum number of objects possible are defined in this MIB, while
still providing as rich a set of management information as possible.
An object is left out of this MIB when it can be derived from other
objects that are provided. Further to the tradition of the SNMP,
computationally intense operations are left to the domain of the
management station. Thus, this MIB provides a set of objects from
which other management information may be derived.
The examples provided in sections 3.3 through 3.5 are not meant to be
comprehensive but are illustrative of the potential uses of the
objects defined by this MIB.
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3.1. Relationship to Other MIBs
3.1.1. DHCP MIB Extensions
The DHCP MIB extensions will be the "dhcp" branch of the standard
MIB-2 tree, as illustrated by the following diagram:
+ -- -- -- -+
| MIB-2 |
+ -- -+ -- -+
|
|
+ -- -+ -- -+
| dhcp |
+ -- -+ -- -+
|
|
+ -- -- -- -- -- -- -- -+ -- -- -- + -- -- -- -- -+ -- -- -- --
-- -- -- -- -- -- -+
| | | |
+ -- -- -+ -- -- -+ + -- -- -+ -- -- + + -- -- -- -+ -- -- -- --
+ + -- -- -- + -- -- -- +
| dhcp-v4 | | dhcp-v4 | | dhcp-v4 | | dhcp-v6 MIB |
|Server MIB | |Client MIB| |Relay Agent MIB | | Extensions |
|(this memo)| | (future) | | (future work) | | (future) |
+ -- -- -- -- -- -+ + -- -- -- -- -- + + -- -- -- -- -- -- -- --
+ + -- -- -- -- -- -- -+
The MIBs will share a common branching point, but are independently
defined.
3.1.2. Host System MIB Extensions
The Host System MIB [RFC1123] provides for information, command, and
control of the host computer system on which a DHCP server resides.
The DHCP Server MIB specifically does not include any objects that
may be accessible using the Host System MIB.
3.1.3. DHCPv6 Server MIB Extensions
When this set of MIB extensions is developed, it will share a common
branch point in the MIB tree with the other DHCP MIB Extensions.
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3.1.4. DHCP Client MIB Extensions
If this set of MIB extensions is ever developed, it will share a
common branch point in the MIB tree with the other DHCP MIB
Extensions, and will use many of the same textual conventions.
3.1.5. DHCP Relay Agent MIB Extensions
If this set of MIB extensions is ever developed, it will share a
common branch point in the MIB tree with the other DHCP MIB
Extensions, and will use many of the same textual conventions.
3.2. Textual Conventions Introduced in this MIB
Several conceptual data types have been introduced as textual
conventions in this DHCP MIB document. These additions will
facilitate the common understanding of information used by the DHCP
server. No changes to the SMI or the SNMP are necessary to support
these conventions.
3.2.1. DhcpTimeInterval
This data type measures time intervals since the beginning of some
epoch in milliseconds.
3.2.2. HardwareAddressType
This data type contains the type of hardware address represented by
MacAddress, as defined for ARP messages.
3.2.3. HardwareAddressLength
The length in octets of MacAddress is contained in this type.
3.2.4. MacAddress
The actual layer 1 hardware address is contained in this data type.
3.2.5. PhysicalAddress
This data type combines the hardware type octet with the length and
hardware (NIC or MAC) address to produce a unique address type.
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3.2.6. DhcpLabel
This data type contains labels used as identifiers by DHCP servers.
3.3. BOOTP and DHCP Counter Groups
This section describes some of the management information that may be
derived from the objects provided in the counter groups.
The total number of valid DHCP packets received by the server is
computed as the sum of the dhcpCountDiscovers, dhcpCountRequests,
dhcpCountReleases, dhcpCountDeclines, dhcpCountInforms and
dhcpCountLeaseQueries objects. The total number of valid packets
(BOOTP and DHCP) received is computed as the total number of valid
DHCP packets plus the value of the bootpCountRequests object. The
total number of packets received is computed as the total number of
valid packets plus the sum of bootpCountInvalids and
dhcpCountInvalids.
Similar to the received computations, the total number of DHCP
packets sent by the server is computed as the sum of the
dhcpCountOffers, dhcpCountAcks, dhcpCountNacks,
dhcpCountForcedRenews, dhcpCountKnowns, and dhcpCountUnknowns
objects. The number of packets (BOOTP and DHCP) sent by the server
is computed as the total number of DHCP packets sent plus the value
of the bootpCountReplies object.
3.4. BOOTP and DHCP Optional Statistics Group
This section describes some of the management information that may be
derived from the objects provided in the optional statistics group.
Given time 1 (t1) and time 2 (t2) greater than t1, the mean inter-
arrival time of valid DHCP messages for the interval t1 to t2 can be
computed as (dhcpStatLastArrivalTime at t2 minus
dhcpStatLastArrivalTime at t1) divided by (valid DHCP received packet
count at t2 minus valid DHCP received packet count at t1).
Under the simplifying assumption that the capture of packet counts
and times is discontinuous (that is, for the measurement interval the
captured data represents the complete set for the server) the
variance of the mean may be computed as
(dhcpStatSumSquaresArrivalTime at t2 less
dhcpStatSumSquaresArrivalTime at t1) divided by (valid DHCP received
packet count at t2 less valid DHCP received packet count at t1).
Standard deviation of the mean is the square root of the variance.
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Calculation of statistics for message response time is entirely
similar to the calculations for inter-arrival time, except that the
response time objects are used for the calculations.
Calculation of statistics for BOOTP is similar to the calculations
for DHCP, except that the similar objects from the
bootpOptionalStatistics group are used instead of the objects from
dhcpOptionalStatistics group.server Configuration Group
The server configuration group contains objects that describe the
configuration information that is contained in the server. Some of
the configuration information is static (e.g., a statically
configured IP address) and some of the configuration is dynamic
(e.g., an assigned DHCP lease). The intent of the server
configuration group is to be able to read the server's configuration.
Mechanisms outside of the SNMP are currently in use (e.g., vendor
defined solutions) and are being standardized (e.g., the Directory
Enabled Networks [DEN] initiative) to update a server's
configuration.
The configuration information defines a minimal set of information
that most servers should be able to provide. Each row of the
serverSubnetTable lists the subnet, the subnet mask, and the subnet
that is equivalent to this subnet. Equivalence is defined as more
than one subnet being present on the same network segment as some
other subnet.
The serverRangeTable lists the start and end IP addresses of the
ranges and the subnet of which the range is a member. The
serverRangeInUse object indicates the amount of the range that is
currently in use, either through dynamic allocation or being
reserved. The range size can be computed by taking the difference of
the serverRangeStart and serverRangeEnd objects.
The serverAddressTable provides information about the static and
dynamic addresses that the server contains in its configuration.
Addresses may be:
o Static, in which case they are predefined though the server's
configuration. Static addresses may or may not have been
previously served by the server;
o Dynamic, in which case the server has served the addresses and
it is currently in active use by a host;
o Expired, in which case the server had previously assigned for
which the lease time has expired, but is retained by the server
for possible future use by the same client;
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o Configuration-reserved, in which case the address is not
available for the server to allocate to a client. A
configuration-reserved address is one that has been reserved by
the administrator. An example of a configuration-reserved
address is an address that is assigned to a client, not through
DHCP (e.g., statically assigned), and the address is within a
DHCP range; and
o Server-reserved, in which case the server has taken the address
out of use. Examples of server-reserved addresses are those
which have been declined (i.e., through a DHCPDECLINE) by a
client or those which have responded to an ICMP echo before they
were assigned.
The protocol used to allocate the address may be determined from the
serverAddressServedProtocol object. This object indicates whether
the address has never been served, or whether BOOTP or DHCP was used
to allocate the address.
3.5. Response Times and ICMP Echo
According to [RFC2131], servers SHOULD try to determine if an address
is in use before assigning it. Some servers choose not to perform
this check, letting the client determine for itself if the address is
in use. Other servers perform an ICMP echo (Ping) just prior to
assigning an address. Servers that perform a Ping before responding
to a DHCPDISCOVER should not include in the response time the time
from when the Ping was transmitted until the time that either a
response was received or that the server timed out waiting for a
response.
4. Definitions
-- definitions for a DHCP (Dynamic Host Configuration Protocol)
server
DHCP-SERVER-MIB DEFINITIONS ::= BEGIN
IMPORTS
Counter64, Counter32, Gauge32, Unsigned32, mib-2, MODULE-IDENTITY,
OBJECT-TYPE, OBJECT-IDENTITY
FROM SNMPv2-SMI
TEXTUAL-CONVENTION, RowStatus, TruthValue, DateAndTime
FROM SNMPv2-TC
SnmpAdminString FROM SNMP-FRAMEWORK-MIB
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InetAddressType, InetAddress, InetAddressIPv4,
InetAddressPrefixLength
FROM INET-ADDRESS-MIB
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF;
dhcp OBJECT-IDENTITY
STATUS current
DESCRIPTION
"The dhcp branch in the standard network management framework."
::= { mib-2 99 } -- IANA will make official assignment
serverMIB MODULE-IDENTITY
REVISION "2002-11-04 04:29Zö
DESCRIPTION "Initial Version, published as RFC xxxx."
-- RFC Editor assigns xxxx
LAST-UPDATED "2002-11-04 04:29Z"
ORGANIZATION "IETF DHC Working Group"
General Discussion: dhcwg@ietf.org
Subscribe: http://www1.ietf.org/mailman/listinfo/dhcwg
Archive: http://www1.ietf.org/mailman/listinfo/dhcwg
Chair: Ralph Droms, rdroms@cisco.com
CONTACT-INFO
" Richard Barr Hibbs
Postal: 952 Sanchex Street
San Francisco, California 94114-3362
USA
Tel: +1-(415)-648-3920
Fax: +1-(415)-648-9017
E-mail: rbhibbs@pacbell.net
Glenn Waters
Postal: Nortel Networks, Inc.
310-875 Carling Avenue
Ottawa, Ontario K1S 5P1
Canada
Tel: +1-(613)-798-4925
E-mail: gww@NortelNetworks.com "
DESCRIPTION
"The MIB module for entities implementing the server side of
the Bootstrap Protocol (BOOTP) and the Dynamic Host
Configuration protocol (DHCP) for Internet Protocol version
4(IPv4). This MIB does not include support for Dynamic DNS
(DDNS) updating nor for the DHCP Failover Protocol."
::= { dhcp 1 }
serverMIBObjects OBJECT-IDENTITY
STATUS current
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DESCRIPTION
"DHCP Server MIB objects are all defined in this branch."
::= { serverMIB 1 }
serverSystem OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Group of objects that are related to the overall system."
::= { serverMIBObjects 1 }
bootpCounters OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Group of objects that count various BOOTP events."
::= { serverMIBObjects 2 }
dhcpCounters OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Group of objects that count various DHCP events."
::= { serverMIBObjects 3 }
bootpOptionalStatistics OBJECT-IDENTITY -- /*renamed*/
STATUS current
DESCRIPTION
"Group of objects that measure various BOOTP statistics."
::= { serverMIBObjects 4 }
dhcpOptionalStatistics OBJECT-IDENTITY -- /*renamed*/
STATUS current
DESCRIPTION
"Group of objects that measure various DHCP statistics."
::= { serverMIBObjects 5 }
serverConfiguration OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Objects that contain pre-configured and dynamic configuration
information."
::= { serverMIBObjects 6 }
bootpClients OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Objects that map BOOTP clients to IP addresses."
::= { serverMIBObjects 7 }
dhcpClients OBJECT-IDENTITY
STATUS current
DESCRIPTION
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"Objects that map DHCP clients to IP addresses."
::= { serverMIBObjects 8 }
-- Textual conventions defined by this memo
DhcpTimeInterval ::= TEXTUAL-CONVENTION
SYNTAX Unsigned32
STATUS current
DESCRIPTION
"The number of milliseconds that has elapsed since some epoch.
Systems that cannot measure events to the millisecond
resolution SHOULD round this value to the next available
resolution that the system supports."
HardwareAddressType ::= TEXTUAL-CONVENTION
SYNTAX OCTET
STATUS current
REFERENCE "RFC 2131"
DESCRIPTION
"The value of the hardware type field, as used in ARP messages
(e.g., 1 for Ethernet, 6 for token ring). IANA maintains the
list of registered numbers for this field."
HardwareAddressLength ::= TEXTUAL-CONVENTION
SYNTAX OCTET
STATUS current
REFERENCE "RFC 2131"
DESCRIPTION
"The length in octets of the hardware address field (e.g., 6
for Ethernet). IANA maintains the list of registered numbers
for this field."
MacAddress ::= TEXTUAL-CONVENTION
SYNTAX OCTET STRING (SIZE (1..16))
DISPLAY-HINT "t,l,xx[:xx...]"
STATUS current
REFERENCE "RFC 2131"
DESCRIPTION
"A Layer 1 address, the hardware address of the MAC (Media
Adapter Card) interface. The address length is fixed for a
given hardware address type, but varies by type."
PhysicalAddress ::= TEXTUAL-CONVENTION
SYNTAX SEQUENCE OF {
HardwareAddressType,
HardwareAddressLength,
MacAddress
}
DISPLAY-HINT "t,l,xx[:xx...]"
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STATUS current
REFERENCE "RFC 2131"
DESCRIPTION
"A Layer 1 address which includes the hardware type space as
well as the usual MAC address. This encoding is intended to
mirror the representation of physical addresses in DHCP."
DhcpLabel ::= TEXTUAL-CONVENTION
SYNTAX SnmpAdminString (SIZE (1..100))
DISPLAY-HINT
STATUS current
DESCRIPTION
-- serverSystem Group
serverSystemDescr OBJECT-TYPE
SYNTAX SnmpAdminString (SIZE (0..255))
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A textual description of the server. This value should
include the full name and version identification of the
server."
::= { serverSystem 1 }
serverSystemObjectID OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The vendor's authoritative identification of the network
management subsystem contained in this entity. This value is
allocated within the SMI enterprise subtree (1.3.6.1.4.1) and
provides an easy and unambiguous means for determining 'what
kind of server' is being managed. For example, if vendor
'VeryBigServers, Inc.' is assigned the subtree
1.3.6.1.4.1.4242, it may assign the identifier
1.3.6.1.4.1.4242.1.1 to its `Hercules DHCP Server'."
::= { serverSystem 2 }
-- dhcpCounters Group
-- DHCP received packet counters
dhcpCountDiscovers OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
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DESCRIPTION
"The number of DHCPDISCOVER (option 53 with value 1) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 1 }
dhcpCountRequests OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPREQUEST (option 53 with value 3) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 2 }
dhcpCountReleases OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPRELEASE (option 53 with value 7) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 3 }
dhcpCountDeclines OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPDECLINE (option 53 with value 4) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 4 }
dhcpCountInforms OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPINFORM (option 53 with value 8) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 5 } -- /*renumbered*/
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dhcpCountLeaseQueries OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPLEASEQUERY (option 53 with value 9) packets
received."
REFERENCE
"draft-ietf-dhc-leasequery-02.txt."
::= { dhcpCounters 6 } -- /*new*/
dhcpCountPlaceHolder1 OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Placeholder for anticipated new DHCP option 53 message type."
REFERENCE
"None."
::= { dhcpCounters 7 } -- /*new*/
dhcpCountPlaceHolder2 OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Placeholder for anticipated new DHCP option 53 message type."
REFERENCE
"None."
::= { dhcpCounters 8 } -- /*new*/
-- DHCP sent packet counters
dhcpCountOffers OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPOFFER (option 53 with value 2) packets
sent."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 9 } -- /*renumbered*/
dhcpCountAcks OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
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DESCRIPTION
"The number of DHCPACK (option 53 with value 5) packets sent."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 10 } -- /*renumbered*/
dhcpCountNacks OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPNACK (option 53 with value 6) packets sent."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpCounters 11 } -- /*renumbered*/
dhcpCountForcedRenews OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPFORCERENEW (option 53 with value TBD)
packets sent."
REFERENCE
"draft-ietf-dhc-pv4-reconfigure-06.txt."
::= { dhcpCounters 12 } -- /*new*/
dhcpCountKnowns OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPKNOWN (option 53 with value TBD) packets
sent."
REFERENCE
"draft-ietf-dhc-leasequery-03.txt."
::= { dhcpCounters 13 } -- /*new*/
dhcpCountUnknowns OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPUNKNOWN (option 53 with value TBD) packets
sent."
REFERENCE
"draft-ietf-dhc-leasequery-03.txt."
::= { dhcpCounters 14 } -- /*new*/
dhcpCountActives OBJECT-TYPE -- /*new*/
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SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPACTIVE (option 53 with value TBD) packets
sent."
REFERENCE
"draft-ietf-dhc-leasequery-03.txt."
::= { dhcpCounters 15 } -- /*new*/
dhcpCountUnimplementeds OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPUNIMPLEMENTED (option 53 with value TBD)
packets sent."
REFERENCE
"draft-ietf-dhc-leasequery-03.txt."
::= { dhcpCounters 16 } -- /*new*/
dhcpCountPlaceHolder3 OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Placeholder for anticipated new DHCP option 53 message types."
REFERENCE
"None."
::= { dhcpCounters 17 } -- /*new*/
dhcpCountPlaceHolder4 OBJECT-TYPE -- /*new*/
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Placeholder for anticipated new DHCP option 53 message types."
REFERENCE
"None."
::= { dhcpCounters 18 } -- /*new*/
-- DHCP packet error counters
dhcpCountInvalids OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The number of DHCP packets received whose DHCP message type
(i.e., option number 53) is not understood or handled by the
server."
::= { dhcpCounters 19 } -- /*renumbered*/
dhcpCountDroppedUnknownClient OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCP packets dropped due to the server not
recognizing or not providing service to the client-id and/or
hardware address received in the incoming packet."
::= { dhcpCounters 20 } -- /*renumbered*/
dhcpCountDroppedNotServingSubnet OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCP packets dropped due to the server not being
configured or not otherwise able to serve addresses on the
subnet from which this message was received."
::= { dhcpCounters 21 } -- /*renumbered*/
-- dhcpOptionalStatistics group
dhcpStatMinArrivalInterval OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The minimum amount of time between receiving two DHCP
messages. A message is received at the server when the server
is able to begin processing the message. This typically occurs
immediately after the message is read into server memory. If
no messages have been received, then this object contains a
zero value."
::= { dhcpOptionalStatistics 1 } -- /*renamed*/
dhcpStatMaxArrivalInterval OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum amount of time between receiving two DHCP
messages. A message is received at the server when the server
is able to begin processing the message. This typically occurs
immediately after the message is read into server memory. If
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no messages have been received, then this object contains a
zero value."
::= { dhcpOptionalStatistics 2 } -- /*renamed*/
dhcpStatLastArrivalTime OBJECT-TYPE
SYNTAX DateAndTime
MAX-ACCESSread-only
STATUS current
DESCRIPTION
"The date and time that the last valid DHCP message was
received by the server. Invalid messages do not cause this
value to change. If no valid messages have been received, then
this object contains a date and time that is all zero."
::= { dhcpOptionalStatistics 3 }
dhcpStatSumSquaresArrivalTime OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sum of the squared DHCP packet inter-arrival times in
microseconds. This value may be used to compute the variance
and standard deviation of the DHCP arrival times. Note that a
microsecond resolution of this object requires a clock
resolution to the millisecond since the square of a millisecond
value produces a value with microsecond resolution."
::= { dhcpOptionalStatistics 4 } -- /*renamed*/
dhcpStatMinResponseTime OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The smallest time interval measured as the difference between
the arrival of a DHCP message at the server and the successful
transmission of the response to that message. A message is
received at the server when the server is able to begin
processing the message. A message is transmitted after the
server has no further use for the message. Note that the
operating system may still have the message queued internally.
The operating system queue time is not to be considered as part
of the response time. Invalid messages do not cause this value
to change. If no valid messages have been received, then this
object contains a zero value."
::= { dhcpOptionalStatistics 5 } -- /*renamed*/
dhcpStatMaxResponseTime OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
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DESCRIPTION
"The largest time interval measured as the difference between
the arrival of a DHCP message at the server and the successful
transmission of the response to that message. A message is
received at the server when the server is able to begin
processing the message. A message is transmitted after the
server has no further use for the message. Note that the
operating system may still have the message queued internally.
The operating system queue time is not to be considered as part
of the response time. Invalid messages do not cause this value
to change. If no valid messages have been received, then this
object contains a zero value."
::= { dhcpOptionalStatistics 6 } -- /*renamed*/
dhcpStatSumResponseTime OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sum of the response time intervals in milliseconds where a
response time interval is measured as the difference between
the arrival of a DHCP message at the server and the successful
transmission of the response to that message. A message is
received at the server when the server is able to begin
processing the message. A message is transmitted after the
server has no further use for the message. Note that the
operating system may still have the message queued internally.
The operating system queue time is not to be considered as part
of the response time. Invalid messages do not cause this value
to change. If no valid messages have been received, then this
object contains a zero value."
::= { dhcpOptionalStatistics 7 } -- /*renamed*/
dhcpStatSumSquaresResponseTime OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sum of the squared DHCP packet response times in micro-
seconds. This value may be used to compute the variance and
standard deviation of the DHCP response times. Note that a
microsecond resolution of this object requires a clock
resolution to the millisecond since the square of a millisecond
value produces a value with microsecond resolution."
::= { dhcpOptionalStatistics 8 } -- /*renamed*/
-- bootpCounters Group
bootpCountRequests OBJECT-TYPE
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SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of packets received that contain a Message Type of
1 (BOOTREQUEST) in the first octet and do not contain option
number 53 (DHCP Message Type) in the options."
REFERENCE
"RFC-1541."
::= { bootpCounters 1 } -- /*renamed*/
bootpCountInvalids OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of packets received that do not contain a Message
Type of 1 (BOOTREQUEST) in the first octet or are not valid
BOOTP packets (e.g., too short, invalid field in packet
header)."
::= { bootpCounters 2 } -- /*renamed*/
bootpCountReplies OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of packets sent that contain a Message Type of 2
(BOOTREPLY) in the first octet and do not contain option number
53 (DHCP Message Type) in the options."
REFERENCE
"RFC-1541."
::= { bootpCounters 3 } -- /*renamed*/
bootpCountDroppedUnknownClients OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of BOOTP packets dropped due to the server not
recognizing or not providing service to the hardware address
received in the incoming packet."
::= { bootpCounters 4 } -- /*renamed*/
bootpCountDroppedNotServingSubnet OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The number of BOOTP packets dropped due to the server not
being configured or not otherwise able to serve addresses on
the subnet from which this message was received."
::= { bootpCounters 5 } -- /*renamed*/
-- bootpOptionalStatistics group
bootpStatMinArrivalInterval OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The minimum amount of time between receiving two BOOTP
messages. A message is received at the server when the server
is able to begin processing the message. This typically occurs
immediately after the message is read into server memory. If
no messages have been received, then this object contains a
zero value."
::= { bootpOptionalStatistics 1 } -- /*renamed*/
bootpStatMaxArrivalInterval OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum amount of time between receiving two BOOTP
messages. A message is received at the server when the server
is able to begin processing the message. This typically occurs
immediately after the message is read into server memory. If
no messages have been received, then this object contains a
zero value."
::= { bootpOptionalStatistics 2 } -- /*renamed*/
bootpStatLastArrivalTime OBJECT-TYPE
SYNTAX DateAndTime
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The date and time that the last valid BOOTP message was
received by the server. Invalid messages do not cause this
value to change. If valid no messages have been received, then
this object contains a date and time that is all zero."
::= { bootOptionalpStatistics 3 } -- /*renamed*/
bootpStatSumSquaresArrivalTime OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The sum of the squared BOOTP packet inter-arrival times in
microseconds. This value may be used to compute the variance
and standard deviation of the BOOTP arrival times. Note that a
microsecond resolution of this object requires a clock
resolution to the millisecond since the square of a millisecond
value produces a value with microsecond resolution."
::= { bootpOptionalStatistics 4 } -- /*renamed*/
bootpStatMinResponseTime OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The smallest time interval measured as the difference between
the arrival of a BOOTP message at the server and the successful
transmission of the response to that message. A message is
received at the server when the server is able to begin
processing the message. A message is transmitted after the
server has no further use for the message. Note that the
operating system may still have the message queued internally.
The operating system queue time is not to be considered as part
of the response time. Invalid messages do not cause this value
to change. If no valid messages have been received, then this
object contains a zero value."
::= { bootpOptionalStatistics 5 } -- /*renamed*/
bootpStatMaxResponseTime OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The largest time interval measured as the difference between
the arrival of a BOOTP message at the server and the successful
transmission of the response to that message. A message is
received at the server when the server is able to begin
processing the message. A message is transmitted after the
server has no further use for the message. Note that the
operating system may still have the message queued internally.
The operating system queue time is not to be considered as part
of the response time. Invalid messages do not cause this value
to change. If no valid messages have been received, then this
object contains a zero value."
::= { bootpOptionalStatistics 6 } -- /*renamed*/
bootpStatSumResponseTime OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
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DESCRIPTION
"The sum of the response time intervals in milliseconds where a
response time interval is measured as the difference between
the arrival of a BOOTP message at the server and the successful
transmission of the response to that message. A message is
received at the server when the server is able to begin
processing the message. A message is transmitted after the
server has no further use for the message. Note that the
operating system may still have the message queued internally.
The operating system queue time is not to be considered as part
of the response time. Invalid messages do not cause this value
to change. If no valid messages have been received, then this
object contains a zero value."
::= { bootpOptionalStatistics 7 } -- /*renamed*/
bootpStatSumSquaresResponseTime OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sum of the squared BOOTP packet response times in micro-
seconds. This value may be used to compute the variance and
standard deviation of the BOOTP response times. Note that a
microsecond resolution of this object requires a clock
resolution to the millisecond since the square of a millisecond
value produces a value with microsecond resolution."
::= { bootpOptionalStatistics 8 } -- /*renamed*/
-- server configurationgroup
-- server shared network table
serverSharedNetworkTable OBJECT-TYPE
SYNTAX SEQUENCE OF serverSharedNetworkEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A list of shared networks that are configured in the server.
A shared network is the logical aggregation of one or more
subnets that share a common network segment (e.g., multi-tapped
coaxial cable, wiring hub, or switch). This table is present
ONLY for those servers that organize the ranges of addresses
available for assignment where a higher-level grouping (i.e.,
the "shared" network) exists above ranges and subnets."
::= { serverConfiguration 1 }
serverSharedNetworkEntry OBJECT-TYPE
SYNTAX ServerSharedNetworkEntry
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MAX-ACCESS not-accessible
STATUS current
INDEX { serverSharedNetworkName }
DESCRIPTION
"A logical row in the serverSharedNetworkTable."
::= { serverSharedNetworkTable 1}
ServerSharedNetworkEntry ::= SEQUENCE {
serverSharedNetworkName DhcpLabel,
serverSharedNetworkFreeAddresses Unsigned32,
serverSharedNetworkReservedAddresses Unsigned32, -- /*new*/
serverSharedNetworkTotalAddresses Unsigned32 --
/*renamed*/
}
serverSharedNetworkName OBJECT-TYPE
SYNTAX DhcpLabel -- /*modified*/
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The name of the shared network, which uniquely identifies an
entry in the serverSharedNetworkTable."
::= { serverSharedNetworkEntry 1 }
serverSharedNetworkFreeAddresses OBJECT-TYPE -- /*renamed*/
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The number of IP addresses which are available within this
shared network. If the server does not count free addresses by
shared network segment, this value will be zero."
::= { serverSharedNetworkEntry 2 } -- /*renumbered*/
serverSharedNetworkReservedAddresses OBJECT-TYPE -- /*new*/
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The number of IP addresses which are reserved (not available
for assignement) within this shared network. If the server
does not count reserved addresses by shared network segment,
this value will be zero."
::= { serverSharedNetworkEntry 3 }
serverSharedNetworkTotalAddresses OBJECT-TYPE -- /*new*/
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
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"The number of IP addresses which are available within this
shared network. If the server does not count total addresses
by shared network segment, this value will be zero."
::= { serverSharedNetworkEntry 4 }
-- server subnet table
serverSubnetTable OBJECT-TYPE
SYNTAX SEQUENCE OF serverSubnetEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A list of subnets that are configured in this server."
::= { serverConfiguration 2 }
serverSubnetEntry OBJECT-TYPE
SYNTAX ServerSubnetEntry
MAX-ACCESS not-accessible
STATUS current
INDEX { serverSubnet }
DESCRIPTION
"A logical row in the serverSubnetTable."
::= { serverSubnetTable 1 }
ServerSubnetEntry ::= SEQUENCE {
serverSubnet InetAddressIPv4,
serverSubnetMask InetAddressPrefixLength,
serverSubnetSharedNetworkName DhcpLabel, -- /*modified*/
serverSubnetFreeAddressLowThreshold Unsigned32,
serverSubnetFreeAddressHighThreshold Unsigned32,
ServerSubnetFreeAddresses Unsigned32 -- /*renamed*/
}
serverSubnet OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS read-only -- /*changed*/
STATUS current
DESCRIPTION
"The IP address of the subnet."
::= { serverSubnetEntry 1 }
serverSubnetMask OBJECT-TYPE
SYNTAX InetAddressPrefixLength
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The subnet mask of the subnet. This MUST be the same as the
value of DHCP option 1 offered to clients on this subnet."
::= { serverSubnetEntry 2 }
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serverSubnetSharedNetworkName OBJECT-TYPE -- /*renamed*/
SYNTAX DhcpLabel -- /*modified*/
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The shared subnet name (used as an index into the server
shared subnet table) to which this subnet belongs. This value
will be null for servers that do not organize or describe
networks in this manner."
::= { serverSubnetEntry 3 }
serverSubnetFreeAddressLowThreshold OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The low threshold for available free addresses in this subnet.
If the value for available free addresses in this subnet
becomes equal to or less than this value, a
serverSubnetFreeAddressLowThreshold event is generated for this
shared network. No more serverSubnetFreeAddressLowThreshold
events will be generated for this subnet during this execution
of the DHCP server until the value for available free addresses
has exceeded the value of
serverSubnetFreeAddressHighThreshold."
::= { serverSubnetEntry 4 }
serverSharedNetworkFreeAddressHighThreshold OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The high threshold for available free addresses in this
subnet. If a serverSubnetFreeAddressLowThreshold event has
been generated for this subnet, and the value for available
free addresses has exceeded the value of
serverSubnetFreeAddressHighThreshold, then a
serverFreeAddressessHigh event will be generated. No more
serverFreeAddressessHigh events will be generated for this
subnet during this execution of the DHCP server until the value
for available free addresses becomes equal to or less than the
value of serverSubnetFreeAddressHighThreshold."
::= { serverSubnetEntry 5 }
-- server range table
serverRangeTable OBJECT-TYPE
SYNTAX SEQUENCE OF serverRangeEntry
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MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A list of ranges that are configured on this server."
::= { serverConfiguration 3 }
serverRangeEntry OBJECT-TYPE
SYNTAX ServerRangeEntry
MAX-ACCESS not-accessible
STATUS current
INDEX { serverRangeStart }
DESCRIPTION
"A logical row in the serverRangeTable."
::= { serverRangeTable 1 }
ServerRangeEntry ::= SEQUENCE {
serverRangeStart InetAddressIPv4,
serverRangeEnd InetAddressIPv4,
serverRangeSubnetMask InetAddressPrefixLength,
serverRangeInUse Gauge32,
serverRangeOutstandingOffers Gauge32
}
serverRangeStart OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The IP address of the first address in the range. The value
of range start must be less than or equal to the value of range
end."
::= { serverRangeEntry 1 }
serverRangeEnd OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The IP address of the last address in the range. The value of
range end must be greater than or equal to the value of range
start."
::= { serverRangeEntry 2 }
serverRangeSubnetMask OBJECT-TYPE
SYNTAX InetAddressPrefixLength
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The subnet address mask for this range."
::= { serverRangeEntry 3 }
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serverRangeInUse OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of addresses in this range that are currently in
use. This number includes those addresses whose lease has not
expired and addresses which have been reserved (either by the
server or through configuration)."
::= { serverRangeEntry 4 }
serverRangeOutstandingOffers OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of outstanding DHCPOFFER messages for this range is
reported with this value. An offer is outstanding if the
server has sent a DHCPOFFER message to a client, but has not
yet received a DHCPREQUEST message from the client nor has the
server-specific timeout (limiting the time in which a client
can respond to the offer message) for the offer message
expired."
::= { serverRangeEntry 5 }
-- server address table
serverAddressTable OBJECT-TYPE
SYNTAX SEQUENCE OF serverAddressEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An optional list of addresses that are known by this server.
The list MUST contain addresses that have not expired. The
list MUST NOT contain addresses that have never been assigned
by the server UNLESS the lease is pre-configured in the server
(e.g., a static lease for a host). Expired leases MAY appear
during the time they are 'remembered' by the server for
subsequent assignment to the same host."
::= { serverConfiguration 4 }
serverAddressEntry OBJECT-TYPE
SYNTAX ServerAddressEntry
MAX-ACCESS not-accessible
STATUS current
INDEX { serverAddress }
DESCRIPTION
"A logical row in the serverAddressTable."
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::= { serverAddressTable 1 }
ServerAddressEntry ::= SEQUENCE {
serverAddress InetAddressIPv4,
serverAddressSubnetMask InetAddressPrefixLength,
serverAddressRange InetAddressIPv4,
serverAddressType INTEGER,
serverAddressTimeRemaining Unsigned32,
serverAddressAllowedProtocol INTEGER,
serverAddressServedProtocol INTEGER,
serverAddressMacAddress OCTET STRING,
serverAddressClientId OCTET STRING,
serverAddressHostName SnmpAdminString,
serverAddressDomainName SnmpAdminString
}
serverAddress OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The IP address of the entry."
::= { serverAddressEntry 1 }
serverAddressSubnetMask OBJECT-TYPE
SYNTAX InetAddressPrefixLength
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The subnet mask (DHCP option 1) provided to the client offered
this address. The subnet, resulting from logically ANDing the
subnet mask with the entry's IP address, must be configured on
this server and appear as a row in the dhcpSubnetTable."
::= { serverAddressEntry 2 }
serverAddressRange OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The starting IP address (serverRangeStart object) of the range
to which this address belongs. If the address does not fall
into one of the configured ranges (e.g., a statically
configured address on a subnet) the range may be 0.0.0.0."
::= { serverAddressEntry 3 }
serverAddressType OBJECT-TYPE
SYNTAX INTEGER {
static(1),
dynamic(2),
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expired(3), -- /*new*/
configuration-reserved(4), -- /*renumbered*/
server-reserved(5) -- /*renumbered*/
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The type of this address. Types are:
(1) Static addresses defined by the server configuration.
(2) Dynamic addresses defined by the server configuration
AND actually assigned by the server.
(3) Expired dynamic addresses, previously assigned by the
server and 'remembered' for subsequent assignment to the
same host.
(4) Addresses reserved (i.e., not assignable) by the server
configuration.
(5) Addresses previously assigned by the server, but
temporarily or permanently removed from assignable state
for some reason, e.g., the server received an ICMP
ECHOREPLY for the IP address or a DHCPDECLINE message
has been received for the IP address."
::= { serverAddressEntry 4 }
serverAddressTimeRemaining OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of seconds until the lease expires. A value of
4294967295 (i.e., 0xFFFFFFFF) should be used for leases that
have a lease time which is 'infinite' and for BOOTP leases."
::= { serverAddressEntry 5 }
serverAddressAllowedProtocol OBJECT-TYPE
SYNTAX INTEGER {
none(1),
bootp(2),
dhcp(3),
bootp-or-dhcp(4)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The type of protocol that is allowed to be used to serve this
address. A type of none (1) indicates that the address is not
available to be served (e.g., a reserved address).Type (2) are
reserved for BOOTP only devices, while type (3) are reserved
for DHCP only devices. A type of bootp-or-dhcp (4) may be
offered to any type of client."
::= { serverAddressEntry 6 }
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serverAddressServedProtocol OBJECT-TYPE
SYNTAX INTEGER {
none(1),
bootp(2),
dhcp(3)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The type of protocol that was used when this address was
assigned. This object will have the value of none (1) if the
address has not been served."
::= { serverAddressEntry 7 }
serverAddressHardwareAddress OBJECT-TYPE
SYNTAX PhysicalAddress
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The hardware type and hardware address of the client that has
been assigned this lease. The first octet of this object
contains the hardware type from the 'htype' field of the BOOTP
packet and the remaining octets contain the hardware address
from the 'chaddr' field of the BOOTP packet. This object may
be empty if the address has not been previously served."
::= { serverAddressEntry 8 }
serverAddressClientId OBJECT-TYPE
SYNTAX OCTET STRING (SIZE (0..255))
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The client-id of the client that has been assigned this lease.
The client-id is the value specified in option 61 (client-id
option) when the lease was assigned. This object may be empty
if the lease has not been previously assigned or if the client-
id option was not specified when the address was assigned."
::= { serverAddressEntry 9 }
serverAddressHostName OBJECT-TYPE
SYNTAX SnmpAdminString (SIZE (1..255))
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The host name (DHCP option 12) the client is configured to
use, or if no host name was configured then the host name that
the client supplied when requesting an address. While this
object has a maximum size of 255 octets, a Fully-Qualified
Domain Name (FQDN) consisting of a Host Name part and a Domain
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Name part is currently limited to 255 octets. Therefore, the
sum of the string lengths for this object and the
serverAddressDomainName must, in practice, be less than 256
octets."
::= { serverAddressEntry 10 }
serverAddressDomainName OBJECT-TYPE
SYNTAX SnmpAdminString (SIZE (1..255))
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The domain name (DHCP option 15) assigned to the client.
While this object has a maximum size of 255 octets, a Fully-
Qualified Domain Name (FQDN) consisting of a Host Name part and
a Domain Name part is currently limited to 255 octets, less the
separator (".") character. Therefore, the sum of the string
lengths for this object and the serverAddressHostName must, in
practice, be less than 256 octets."
::= { serverAddressEntry 11 }
-- Server Client Table
serverClientTable OBJECT-TYPE
SYNTAX SEQUENCE OF serverClientEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A list of clients that are known by this server. Details
about the clients may be found by indexing into the
serverAddressTable using the serverClientHardwareAddress and
serverClientAddress objects. This table is indexed first by
the MAC address of the client and then by the subnet address on
which the client resides. The subnet is included as an index
since a MAC address is only guaranteed to be unique within a
subnet (i.e., a MAC address is not globally unique)."
::= { serverConfiguration 5 }
serverClientEntry OBJECT-TYPE
SYNTAX ServerClientEntry
MAX-ACCESS not-accessible
STATUS current
INDEX { serverClientHardwareAddress, serverClientAddress }
DESCRIPTION
"A logical row in the serverClientTable. An entry in this
table may be a client that requested an address but was refused
(e.g., not authorized).Servers MAY track these types of clients
if desired and may choose to remove such client entries using a
server defined algorithm. As an example, a server may choose
to keep client request that does not map to an address for a
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one hour time period before removing that entry from this
table."
::= { serverClientTable 1 }
ServerClientEntry ::= SEQUENCE {
serverClientHardwareAddress PhysicalAddress
serverClientAddress InetAddressIPv4,
serverClientSubnetMask InetAddressPrefixLength,
serverClientLastRequestTime DateAndTime,
serverClientLastRequestType INTEGER,
serverClientLastResponseType INTEGER
}
serverClientHardwareAddress OBJECT-TYPE
SYNTAX PhysicalAddress
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The hardware type and hardware address of the client that has
been assigned this lease. The first octet of this object
contains the hardware type from the 'htype' field of the BOOTP
packet and the remaining octets contain the hardware address
from the 'chaddr' field of the BOOTP packet."
::= { serverClientEntry 1 }
serverClientAddress OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The IP address of the entry. May be used to index into the
serverAddressTable. May be 0.0.0.0 if an address is not
associated with this client."
::= { serverClientEntry 2 }
serverClientSubnetMask OBJECT-TYPE
SYNTAX InetAddressPrefixLength
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The subnet mask (DHCP option 1) applied to
serverClientAddress."
::= { serverClientEntry 3 }
serverClientLastRequestTime OBJECT-TYPE
SYNTAX DhcpTimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The timestamp of the last request received, to millisecond
precision if available on the server."
::= { serverClientEntry 4 }
serverClientLastRequestType OBJECT-TYPE
SYNTAX INTEGER {
bootprequest(0)
dhcpdiscover(1),
dhcprequest(3),
dhcpdecline(4),
dhcprelease(7),
dhcpinform(8)
dhcpleasequery(TBD), -- /*new*/
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The type of the last request message received for this
client.If the server does not capture this information, the
value 32,767 is returned."
REFERENCE
"RFC2131; RFC2132, section 9.6; draft-ietf-dhc-leasequery-
02.txt."
::= { serverClientEntry 5 }
serverClientLastResponseType OBJECT-TYPE
SYNTAX INTEGER {
bootpreply(1),
dhcpoffer(2),
dhcpack(5),
dhcpnak(6)
dhcpknown(TBD), -- /*new*/
dhcpunknown(TBD) -- /*new*/
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The type of the last response message sent to this client. If
the server does not capture this information, the value 32,767
is returned."
REFERENCE
"RFC2131; RFC2132, section 9.6;draft-ietf-dhc-pv4-reconfigure-
06.txt;draft-ietf-dhc-leasequery-02.txt"
::= { serverClientEntry 6 }
-- serverNotifyObjects: Objects which are used only in notifications
serverNotifyDuplicateIpAddress OBJECT-TYPE
SYNTAX InetAddressIPv4
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MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The IP address found to be a duplicate. Duplicates are
detected by servers which issue an ICMP ECHOREQUEST prior to
offering an IP address lease."
::= { serverNotifyObjects 1 }
serverNotifyDuplicateMAC OBJECT-TYPE
SYNTAX PhysicalAddress
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The offending MAC address which caused a duplicate IP address
to be detected, if captured by the server, else 00-00-00-00-00-
00."
::= { serverNotifyObjects 2 }
serverNotifyClientDuplicateIP OBJECT-TYPE -- /*renamed*/
SYNTAX InetAddressIPv4
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The IP Address offered by a server that the requesting client
has determined to be a duplicate, detected by means of a
gratuitous ARP message and reported through a DHCPDECLINE
message."
::= { serverNotifyObjects 3 }
-- Notifications
serverMIBNotificationPrefix OBJECT IDENTIFIER
::= { serverMIB 2 }serverMIBNotifications OBJECT IDENTIFIER
::= { serverMIBNotificationPrefix 0 }
serverFreeAddressLow NOTIFICATION-TYPE
OBJECTS {
serverSharedNetworkFreeAddressLowThreshold,
serverSharedNetworkFreeAddresses
}
STATUS current
DESCRIPTION
"This notification signifies that the number of available IP
addresses for a particular shared network has fallen below the
value of serverSharedNetworkFreeAddressLowThreshold for that
shared network."
::= { serverMIBNotifications 1 }
serverFreeAddressHigh NOTIFICATION-TYPE
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OBJECTS {
serverSharedNetworkFreeAddressHighThreshold,
serverSharedNetworkFreeAddresses
}
STATUS current
DESCRIPTION
"This notification signifies that the number of available IP
addresses for a particular shared network has risen above the
value of serverSharedNetworkFreeAddressHighThreshold for that
shared network."
::= { serverMIBNotifications 2 }
serverServerStart NOTIFICATION-TYPE
OBJECTS { serverNotifyClientDuplicateIP }
STATUS current
DESCRIPTION
"This notification signifies that the server of the specified
type has started on the host from which this notification has
been sent."
::= { serverMIBNotifications 3 }
serverServerStop NOTIFICATION-TYPE
OBJECTS { serverNotifyClientDuplicateIP }
STATUS current
DESCRIPTION
"This notification signifies that the server of the specified
type has stopped normally on the host from which this
notification has been sent."
::= { serverMIBNotifications 4 }
serverDuplicateAddress NOTIFICATION-TYPE
OBJECTS {
serverNotifyDuplicateIpAddress,
serverNotifyDuplicateMAC,
serverNotifyClientDuplicateMAC
}
STATUS current
DESCRIPTION
"This notification signifies that a duplicate IP address has
been detected. The DHCP server can detect this condition
through the ping-before-offer mechanism. Alternatively, the
client may have sent a DHCPDECLINE back to the server; this is
assumed to be the result of the client detecting that the
address was in use. In either case, the DHCP server marks the
IP address as unavailable for leasing to clients. The
serverNotifyClientDuplicateMAC object indicates whether the
client or server detected this condition."
::= { serverMIBNotifications 5 } -- /*renumbered*/
serverAddressConflict NOTIFICATION-TYPE
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OBJECTS { serverNotifyClientDuplicateIP }
STATUS current
DESCRIPTION
::= { serverMIBNotifications 6 } -- /*renumbered*/
-- Conformance
serverMIBConformanceOBJECT-IDENTITY
STATUS current
DESCRIPTION
"DHCP Server MIB objects are all defined in this branch."
::= { serverMIB 3 }
serverMIBCompliancesOBJECT IDENTIFIER
::= { serverMIBConformance 1 }
serverMIBGroupsOBJECT IDENTIFIER
::= { serverMIBConformance 2 }
-- Compliance groups
serverMIBCompliance MODULE-COMPLIANCE
MODULE -- this module
MANDATORY-GROUPS {
serverSystemGroup,
bootpCountersGroup,
dhcpCountersGroup,
serverConfigurationGroup,
serverClientsGroup
}
OPTIONAL-GROUPS {
bootpOptionalStatisticsGroup,
dhcpOptionalStatisticsGroup
}
STATUS current
DESCRIPTION
"Describes the requirements for conformance to the DCHP Server
MIB"
::= { serverMIBCompliances 1 }
-- Object groups
serverSystemGroup OBJECT-GROUP
OBJECTS {
serverSystemDescr,
serverSystemObjectID
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}
STATUS current
DESCRIPTION
"Objects belonging to the serverSystemGroup."
::= { serverMIBGroups 1 }
bootpCountersGroup OBJECT-GROUP
OBJECTS {
bootpCountRequests,
bootpCountInvalids,
bootpCountReplies,
bootpCountDroppedUnknownClients,
bootpCountDroppedNotServingSubnet
}
STATUS current
DESCRIPTION
"Objects belonging to the bootpBountersGroup."
::= { serverMIBGroups 2 }
dhcpCountersGroup OBJECT-GROUP
OBJECTS {
dhcpCountDiscovers,
dhcpCountRequests,
dhcpCountReleases,
dhcpCountDeclines,
dhcpCountInforms,
dhcpCountLeaseQueries
dhcpCountPlaceHolder1
dhcpCountPlaceHolder2
dhcpCountOffers,
dhcpCountAcks,
dhcpCountNacks,
dhcpCountForcedRenews
dhcpCountKnowns
dhcpCountUnknowns
dhcpCountActives
dhcpCountUnimplementeds
dhcpCountPlaceHolder3
dhcpCountPlaceHolder4
dhcpCountInvalids,
dhcpCountDroppedUnknownClient,
dhcpCountDroppedNotServingSubnet
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpCountersGroup."
::= { serverMIBGroups 3 }
bootpOptionalStatisticsGroup OBJECT-GROUP
OBJECTS {
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Internet Draft DHCP Server MIB November 2002
bootpStatMinArrivalInterval,
bootpStatMaxArrivalInterval,
bootpStatLastArrivalTime,
bootpStatSumSquaresArrivalTime,
bootpStatMinResponseTime,
bootpStatMaxResponseTime,
bootpStatSumReponseTime,
bootpStatSumSquaresResponseTime
}
STATUS current
DESCRIPTION
"Objects belonging to the bootpOptionalStatisticsGroup."
::= { serverMIBGroups 4 }
dhcpOptionalStatisticsGroup OBJECT-GROUP
OBJECTS {
dhcpStatMinArrivalInterval,
dhcpStatMaxArrivalInterval,
dhcpStatLastArrivalTime,
dhcpStatSumSquaresArrivalTime,
dhcpStatMinResponseTime,
dhcpStatMaxResponseTime,
dhcpStatSumResponseTime,
dhcpStatSumSquaresResponseTime
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpOptionalStatisticsGroup."
::= { serverMIBGroups 5 }
serverConfigurationGroup OBJECT-GROUP
OBJECTS {
serverSubnet,
serverSubnetMask,
serverSubnetSharedNetwork,
serverRangeStart,
serverRangeEnd,
serverRangeSubnetMask,
serverRangeInUse,
serverRangeOutstandingOffers,
serverAddress,
serverAddressSubnetMask,
serverAddressRange,
serverAddressType,
serverAddressTimeRemaining,
serverAddressAllowedProtocol,
serverAddressServedProtocol,
serverAddressHardwareAddress,
serverAddressClientId,
serverAddressHostName,
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serverAddressDomainName
}
STATUS current
DESCRIPTION
"Objects belonging to the serverConfigurationGroup."
::= { serverMIBGroups 6 }
serverClientsGroup OBJECT-GROUP
OBJECTS {
serverClientHardwareAddress,
serverClientSubnetMask,
serverClientAddress,
serverClientLastRequestTime,
serverClientLastRequestType,
serverClientLastResponseType
}
STATUS current
DESCRIPTION
"Objects belonging to the serverClientsGroup."
::= { serverMIBGroups 7 }
serverSharedNetworkObjectsGroup OBJECT-GROUP
OBJECTS {
serverSharedNetworkFreeAddressLowThreshold,
serverSharedNetworkFreeAddressHighThreshold,
serverSharedNetworkFreeAddressValue
}
STATUS current
DESCRIPTION
"DHCP Server MIB objects used in shared networks."
::= { serverMIBGroups 8 }
serverNotifyObjectsGroup OBJECT-GROUP
OBJECTS {
serverNotifyDuplicateIpAddress,
serverNotifyDuplicateMAC,
serverNotifyClientDuplicateMAC,
serverNotifyClientDuplicateIP,
serverNotifyContestedIpAddress
}
STATUS current
DESCRIPTION
"DHCP Server MIB objects used in notifications."
::= { serverMIBGroups 9 }
serverNotificationsGroup NOTIFICATION-GROUP
NOTIFICATIONS {
serverFreeAddressLow,
serverFreeAddressHigh,
serverServerStart,
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serverServerStop,
serverDNSQueueTooBig,
serverOtherServerNotResponding,
serverDuplicateAddress,
serverAddressConflict,
serverOtherServerResponding,
serverFailoverConfigMismatch
}
STATUS current
DESCRIPTION
"Notifications that are implemented by the DHCP Server agent."
::= { serverMIBGroups 10 }
END
5. Intellectual Property
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11.
Copies of claims of rights made available for publication and any
assurances of licenses to be made available, or the result of an
attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this
specification can be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
6. Notes
This section will be removed when this memo goes to Working Group
Last Call.
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6.1. Issues
Not all of these issues have been resolved, even in the latest (-07)
draft. Some may become items for future study, while some will
probably be dropped.
o Are placeholders for expected DHCP option values a good or bad
idea?
o Ryan Troll proposed four or five traps that Nathan Lane
enthusiastically supported, but it has been difficult to achieve
any consensus (or, for that matter, much interest) in them.
o What is the best way to reset counters and statistics? Is it
necessary to reset them at all? The -07 draft does not declare
any counters as read-write or read-create, primarily to avoid
these questions, as well as to provide fundamental security over
objects.
-- Do we need to reset them individually, as groups, or as a
whole?
-- Do we need a timestamp of when they were reset?
o Should all invalid packets received be collapsed into a single
counter for each protocol type (BOOTP and DHCP), or broken out by
type of error?
o If counted by error type, what is the set of errors that we should
use?
o Perhaps we should develop a common vocabulary (and glossary) for
terms such as "abandoned" so that the objects defined and their
descriptions aren't misinterpreted by implementers.
o Do we need to be concerned about the potential size of some of the
configuration data tables? Wouldn't it be better to maintain
counters for things like number of leases assigned than to expect
the management station to calculate the values by reading very
large tables to count the number of leases in that state?
6.2. Changes from Prior Drafts
The "-01" revision removed the Server Identity section from the
proposed MIB, relying on the Application MIB to accomplish the same
result.
The min/max (inter-arrival and response times) were changed to
Unsigned32 so that they could be reset. Sums of inter-arrival and
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response times were deleted since the management station can easily
calculate them. The last arrival time objects were added.
The "-03" version incorporated the proposed configuration tables
suggested by Ryan Troll of CMU. The "01" revision of this version
added three elements to the server subnet table, number of
outstanding offers, number of addresses in use, and number of free
addresses, as well as changing subnet address to subnet mask in the
server address, server range, and client address tables. The client
MAC address element of the client address table was separated into a
1-octet hardware type and a 16-octet client hardware address, causing
a renumbering of the elements in this table. Clarifying text was
added to several element descriptions, and limitations on values, and
the reported value when the server did not support the data element
were also specified. This version also incorporated an address
change for one of the authors, revisions to standard text required by
the IETF, and some editorial clarifications.
The "-04" version changed the maximum size of the object
serverAddressHostName from 64 to 255 octets, and added clarifying
text to both that object and to serverAddressDomainName regarding the
practical values for the length of both objects.
The "-05" version added a number of traps suggested by Kim Kinnear,
made a number of small renaming and renumbering changes (annotated in
the MIB itself) and added the Shared Network concept to describe
shared network segments: several subnetworks that coexist on one
medium. This was done partly because the Address Range concept did
not adequately describe the "scoping" of address pools as is common
with many current server implementations. Also updated the authorÆs
address and contact information, and incorporated a number of
corrections and amplifications suggested by various readers of the "-
04" draft, including a missing OID for serverNotifyObjects and a
syntax error for PhysicalAddress.
The "-06" version corrects a number of flaws reported by Rick Geesen
and Jin Tao, mostly caused by typographical errors in the "-05"
version as well as some unintentionally omitted text for
serverNotifyObjects. The "-06" version also changes BOOTP and DHCP
statistics from mandatory to optional, renaming object identifiers as
required to match. All objects, tables, and groups in previous
drafts for Dynamic DNS updating and Failover have been removed. All
tables were carefully examined to be certain that they really could
be simply implemented. Many items were renamed or renumbered.
Placeholder definitions of message types (both requests and
responses) were added to support DHCPFORCERENEW, DHCPQUERY,
DHCPKNOWN, and DHCPUNKNOWN. A few [more] typographical errors were
found and fixed. Finally, some of the boilerplate text was brought
in line with standard requirements for Internet-Drafts.
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The "-07" version fixes a few typographical errors (wrong
capitalization of object identifiers and table entry values, spacing
of comments, and misspelled words) in preparation for Working Group
Last Call. Many thanks to Rich Woundy for his detailed and extremely
helpful suggestions on the prior draft. The standard boilerplate
(ôThe SNMP Management Frameworkö) for all new MIBs was added as
section 2 and the standard references not previously included in
section 9 were added. DisplayString objects were recast as
SnmpAdminString types to be consistent with current practice. The
IpAddress type was replaced by IpAddressIPv4 and
IpAddressPrefixLength as appropriate for true addresses and subnet
masks throughout the MIB. Numbering of OIDs was made consistent, and
place holders for anticipated new DHCP message type codes were
explicitly added, eliminating gaps in the OID numbering scheme.
7. Acknowledgements
This document is the result of work undertaken the by DHCP working
group. The editors would like to particularly acknowledge the
development team from Carnegie-Mellon University whose work creating
a private MIB for their DHCP server inspired the development of this
proposal. In particular, many thanks to Ryan Troll who provided a
great deal of useful feedback during the development of this MIB.
Thanks to Nathan Lane, Kim Kinnear, Yannick Koehler, Nathan Lane,
Rick Geesen, Jin Tao, James Brister, Alan Hackert, and Patrick Cosmo
for their review, comments, and contributions. Special thanks to
Rich Woundy for his excellent suggestions that contributed to the û07
draft: any lingering errors are to be blamed solely on me.
8. Security Considerations
There are no management objects defined in this MIB that have a MAX-
ACCESS clause of read-write or read-create. Such objects may be
considered sensitive or vulnerable in some environments. The support
for SET operations in a non-secure environment without proper
protection can have a negative effect on network operations. Many
network administrators object to settable management objects because
of the limited security features of SNMPv1 and SNMPv2. We have
chosen not to fight that battle in constructing this MIB. So, if
this MIB is implemented correctly, then there is no risk that an
intruder can alter or create any management objects of this MIB via
direct SNMP SET operations.
-- for all MIBs you must evaluate
There are a number of managed objects in this MIB that may contain
sensitive information. These are:
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o serverRangeTable
o serverAddressTable
These two objects, in conjunction, provide an observer with a current
view of the available and assigned addresses allocated by this
server. Such knowledge can be used to manually configure a host
computer with a valid IP address for the network managed by the DHCP
server. This could be part of either a Theft of Service scheme or a
Denial of Service attack wherein rogue (pseudo-)hosts simply claim
and defend IP addresses either to subvert accounting for their use or
to disrupt the network for legitimate hosts.
It is thus important to control even GET access to these objects and
possibly to even encrypt the values of these objects when sending
them over the network via SNMP. Not all versions of SNMP provide
features for such a secure environment.
SNMPv1 by itself is not a secure environment. Even if the network
itself is secure (for example by using IPSec), even then, there is no
control as to who on the secure network is allowed to access and
GET/SET (read/change/create/delete) the objects in this MIB.
It is recommended that the implementers consider the security
features as provided by the SNMPv3 framework. Specifically, the use
of the User-based Security Model RFC 2574 [RFC2574] and the View-
based Access Control Model RFC 2575 [RFC2575] is recommended.
It is then a customer/user responsibility to ensure that the SNMP
entity giving access to an instance of this MIB, is properly
configured to give access to the objects only to those principals
(users) that have legitimate rights to indeed GET or SET
(change/create/delete) them.
Denial of Service attacks on a DHCP server are conceivable by
flooding the SNMP (sub-)agent with requests, tying up host system and
server resources processing SNMP messages. The authors know of no
way to wholly prevent such attacks, but have attempted to construct
relatively simple tables to minimize the work required to respond to
messages.
9. References
[DEN] Directory Enabled Networks Working Group,
http://www.universe.digex.net/~murchiso/den.
[RFC1123] R. Braden, "Requirements for Internet Hosts -- Application
and Support," RFC 1123, October 1989.
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Internet Draft DHCP Server MIB November 2002
[RFC1155] Rose, M., and K. McCloghrie, "Structure and Identification
of Management Information for TCP/IP-based Internets", STD 16, RFC
1155, May 1990.
[RFC1157] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
Network Management Protocol", STD 15, RFC 1157, May 1990.
[RFC1212] Rose, M., and K. McCloghrie, "Concise MIB Definitions", STD
16, RFC 1212, March 1991.
[RFC1215] M. Rose, "A Convention for Defining Traps for use with the
SNMP", RFC 1215, March 1991.
[RFC1901] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
"Introduction to Community-based SNMPv2", RFC 1901, January 1996.
[RFC1905] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
"Protocol Operations for Version 2 of the Simple Network Management
Protocol (SNMPv2)", RFC 1905, January 1996.
[RFC1906] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
"Transport Mappings for Version 2 of the Simple Network Management
Protocol (SNMPv2)", RFC 1906, January 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels," RFC 2119, BCP 14, March 1997.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol," RFC 2131,
March 1997.
[RFC2132] Alexander, S. and Droms, R., "DHCP Options and BOOTP Vendor
Extensions," RFC 2132, March 1997.
[RFC2287] Krupczak, C. and Saperia, J., "Definitions of System-Level
Managed Objects for Applications," RFC 2287, February 1998.
[RFC2570] Case, J., Mundy, R., Partain, D., and B. Stewart,
"Introduction to Version 3 of the Internet-standard Network
Management Framework", RFC 2570, April 1999.
[RFC2571] Harrington, D., Presuhn, R., and B. Wijnen, "An
Architecture for Describing SNMP Management Frameworks", RFC 2571,
April 1999.
[RFC2572] Case, J., Harrington D., Presuhn R., and B. Wijnen,
"Message Processing and Dispatching for the Simple Network
Management Protocol (SNMP)", RFC 2572, April 1999.
[RFC2573] Levi, D., Meyer, P., and B. Stewart, "SNMPv3 Applications",
RFC 2573, April 1999.
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Internet Draft DHCP Server MIB November 2002
[RFC2574] Blumenthal, U., and B. Wijnen, "User-based Security Model
(USM) for version 3 of the Simple Network Management Protocol
(SNMPv3)", RFC 2574, April 1999.
[RFC2575] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based
Access Control Model (VACM) for the Simple Network Management
Protocol (SNMP)", RFC 2575, April 1999.
[RFC2578] Case, J., McCloghrie, K., Perkins, D., Rose, M.,
Schoenwaelder, J., and S. Waldbusser, "Structure of Management
Information for Version 2 of the Simple Network Management Protocol
(SNMPv2)," RFC 2578, April 1999.
[RFC2579] Case, J., McCloghrie, K., Rose, M., Schoenwaelder, J., and
S. Waldbusser, "Textual Conventions for Version 2 of the Simple
Network Management Protocol (SNMPv2)," RFC 2579, April 1999.
[RFC2580] Case, J., McCloghrie, K., Rose, M., Schoenwaelder, J., and
S. Waldbusser, "Conformance Statements for Version 2 of the Simple
Network Management Protocol (SNMPv2)," RFC 2580, April 1999.
[RFC3203 , Yves T'Joens and Christian Hublet, Peter De Schrijver,
"The DHCP Reconfigure Extension," July 2001
<draft-ietf-dhc-leasequery-03.txt> Rich Woundy and Kim Kinnear, "DHCP
Lease Query," March 2002
10. Editors' Addresses
Richard Barr Hibbs
952 Sanchez Street
San Francisco, California 94114-3362
USA
Phone: +1-(415)-648-3920
Fax: +1-(415)-648-9017
Email: rbhibbs@pacbell.net
Glenn Waters
Nortel Networks
310-875 Carling Avenue,
Ottawa, Ontario K1S 5P1
Canada
Phone: +1-(613)-798-4925
Email: gww@NortelNetworks.com
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11. Full Copyright Statement
Copyright (C) The Internet Society, 2002. All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works.However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Hibbs & Waters Expires: Nov 2002 + 6 months [Page 49]
