Internet DRAFT - draft-ietf-dhc-server-mib
draft-ietf-dhc-server-mib
Network Working Group Barr Hibbs
INTERNET-DRAFT (no affiliation)
Category: Standards Track Glenn Waters
Nortel Networks
February 2004
Dynamic Host Configuration Protocol for IPv4 (DHCPv4) Server MIB
<draft-ietf-dhc-server-mib-10.txt>
Saved Friday, February 06, 2004, 4:33:38 PM
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-
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or made obsolete by other documents at
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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
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Copyright Notice
Copyright (C), 2003, 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 for IPv4
(DHCPv4) and Bootstrap Protocol (BOOTP) servers.
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Table of Contents
1. Introduction...................................................2
2. The Internet-Standard Management Framework.....................3
3. Overview.......................................................3
3.1. Relationship to Other MIBs.................................4
3.1.1. DHCP MIB Extensions....................................4
3.1.2. Host System MIB Extensions.............................4
3.1.3. DHCP Client MIB Extensions.............................4
3.1.4. DHCP Relay Agent MIB Extensions........................5
3.1.5. DHCPv6 MIB Extensions..................................5
3.2. Textual Conventions Introduced in this MIB.................5
3.2.1. Dhcpv4PhysicalAddress..................................5
3.3. BOOTP and DHCP Counter Groups..............................5
3.3.1. Discontinuities........................................6
3.3.2. Counter Rollover.......................................7
3.4. Server Configuration Group.................................7
4. Definitions....................................................9
5. Intellectual Property.........................................33
6. Acknowledgements..............................................33
7. IANA Considerations...........................................33
8. Security Considerations.......................................34
9. References....................................................35
9.1. Normative References......................................35
9.2. Informative References....................................35
10. Editors' Addresses...........................................36
11. Full Copyright Statement.....................................36
1. Introduction
This memo is a product of 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 DHCPv4 and
Bootstrap Protocol (BOOTP) servers implement. Many implementations
support both DHCPv4 and BOOTP within a single server and hence this
memo describes the MIB for both DHCPv4 and BOOTP servers.
This memo does not cover DHCPv4/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.
Provision is also made for Standards-Track additions to the DHCP
Message Type (option 61.)
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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 using 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 [RFC2119].
2. The Internet-Standard Management Framework
For a detailed overview of the documents that describe the current
Internet-Standard Management Framework, please refer to section 7 of
RFC 3410 [RFC3410], Managed objects are accessed via a virtual
information store, termed the Management Information Base or MIB.
MIB objects are generally accessed through the Simple Network
Management Protocol (SNMP). Objects in the MIB are defined using
the mechanisms defined in the Structure of Management Information
(SMI). This memo specifies a MIB module that is compliant to the
SMIv2, which is described in STD 58, [RFC2578], STD 58, [RFC2579]
and STD 58, [RFC2580].
3. Overview
In the tradition of the Simple Network Management Protocol (SNMP),
the minimum number of objects possible is 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 can be derived.
Provision for future extensions to cover DHCPv4 clients and relay
agents, and DHCPv6 extensions are implied by the top-level structure
illustrated in section 3.1.1.
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 DHCP MIBs share a common branching point but will be
independently defined by individual memos.
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. DHCP Client MIB Extensions
Development of this set of MIB extensions is a natural path given
the increasing interest in desktop and client system management. It
will share a common branch point in the MIB tree with the other DHCP
MIB Extensions, and may use many of the same textual conventions.
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3.1.4. 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.
3.1.5. DHCPv6 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 likely use very different textual conventions
as the protocol differs significantly from DHCPv4.
3.2. Textual Conventions Introduced in this MIB
One conceptual data type has been introduced in this document. No
changes to the SMI or SNMP are necessary to support this convention.
3.2.1. Dhcpv4PhysicalAddress
This data type contains the type of hardware address represented by
MacAddress, as defined for ARP messages, the length in octets of
MacAddress, and the actual layer 1 hardware address.
3.3. BOOTP and DHCP Counter Groups
This section describes some of the management information that can
be derived from the objects provided in the counter groups.
In this context, a "valid" packet is one which has an identifiable
message type and has passed all format and validation checks that
the DHCP server implements. Not all servers validate received
packets in the same way, so there will be differences in the counts
reported by different servers. It is appropriate to simply accept
the server's notion of what constitutes a valid packet.
The total number of valid DHCP packets received by the server is
computed as:
(dhcpv4CountDiscovers + dhcpv4CountRequests +
dhcpv4CountReleases + dhcpv4CountDeclines + dhcpv4CountInforms
+ dhcpv4CountLeaseQueries)
The total number of valid packets (BOOTP and DHCP) received is
computed as:
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(total number of valid DHCP packets) + bootpCountRequests)
The total number of packets received is computed as:
(total number of valid packets) + bootpCountInvalids +
dhcpv4CountInvalids
Similar to the received computations, the total number of DHCP
packets sent by the server is computed as:
dhcpv4CountOffers + dhcpv4CountAcks + dhcpv4CountNaks
The number of packets (BOOTP and DHCP) sent by the server is
computed as:
(total number of DHCP packets sent) + (bootpCountReplies)
3.3.1. Discontinuities
Hosts for DHCP servers, and the DHCP servers themselves, are
generally quite reliable but occasionally counter values may be
discontinuous between successive GETs. There are several cases of
interest:
o Server fails and is restarted, resetting all counters to zero.
o Server fails and is restarted, with counters in an unknown
state.
o Server fails and is restarted, with counters restored to some
previously checkpointed value.
The first case MAY occur when a server and agent are incapable of
restarting to a "last known good" state, and a manager MUST be
capable of recognizing this case. There is little a manager can do
other than recognize a reset to zero has occurred and continue from
the point of restart.
The second case is currently the Best Current Practice for SNMP
managers. Because of the uncertain state of counters following a
server restart, a manager MUST discard data from the outage interval
and restart its calculations.
The third case SHOULD arise only if agents take periodic snapshots
at different intervals than responding to a GET request. While the
counts reported in the first GET response following the outage were
accurate at some time, they MAY NOT be completely current. If this
occurs, the manager MAY have to accept that data has been lost,
perhaps discarding accumulated data, and continue.
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3.3.2. Counter Rollover
Counter objects increment at different rates. It can be expected
that some counter will reach its maximum value and rollover to zero
while others are nowhere near their maximum value. When a counter's
value at time t2 is less than its value at time t1, the manager
SHOULD initially assume that a discontinuity has occurred and
perform appropriate data validation to determine if the value has
rolled over. If a single rollover has occurred, the value used in
calculation SHOULD be:
[(maximum value of counter) - (value at time t1)] + (value at
time t2) + 1
Managers SHOULD be alert to the possibility of a counter rolling
over more than once during the sampling interval. If this is
likely to occur (due to very short leases, very large numbers of
clients, network topology, and the presence of unreliable clients
or intermediate network equipment) a manager SHOULD carefully
examine each detected counter rollover to determine if the data
can be used or should be discarded.
3.4. Server Configuration Group
The server configuration group contains objects that describe the
client host configuration information that is held in the server to
be offered to requesting clients. Some of the configuration
information is static (e.g., a statically configured IPv4 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.
The configuration information defines a minimal set of information
that most servers should be able to provide. Each row of the
dhcpv4ServerSubnetTable lists the subnet address, the subnet mask,
and the shared network name that is equivalent to the subnet.
Equivalence is defined as more than one subnet being present on the
same network segment as some other subnet.
The dhcpv4ServerRangeTable lists the start and end IPv4 addresses of
the ranges and the subnet of which the range is a member. The
dhcpv4ServerRangeInUse 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 as:
dhcpv4ServerRangeStartAddress - dhcpv4ServerRangeEndAddress +
1
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The dhcpv4ServerClientTable provides information about the static
and dynamic addresses that the server contains in its configuration.
Addresses can 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 the
address, but the lease time has expired and is retained by the
server for possible future use by the same client;
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
that have been declined (i.e., through a DHCPDECLINE) by a
client or those that have responded to an ICMP echo before they
were assigned.
The protocol used to allocate the address can be determined from the
"dhcpv4ServerClientServedProtocol" object. This object indicates
whether the address has never been served, or whether BOOTP or DHCP
was used to allocate the address.
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4. Definitions
DHCP-SERVER-MIB DEFINITIONS ::= BEGIN
IMPORTS
Counter64, Gauge32, Unsigned32, MODULE-IDENTITY, OBJECT-TYPE,
OBJECT-IDENTITY, NOTIFICATION-TYPE, mib-2
FROM SNMPv2-SMI
TEXTUAL-CONVENTION, DateAndTime FROM SNMPv2-TC
SnmpAdminString FROM SNMP-FRAMEWORK-MIB
InetAddressIPv4, InetAddressPrefixLength
FROM INET-ADDRESS-MIB
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF;
dhcp MODULE-IDENTITY
LAST-UPDATED "200402061633Z"
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 Sanchez 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
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4(IPv4). This MIB does not include support for Dynamic DNS
(DDNS) updating nor for the DHCP Failover Protocol.
Copyright (C) The Internet Society (2003). This version of
this MIB module is part of RFC xxxx; see the RFC itself for
full legal notices."
-- RFC Editor assigns xxxx and removes this comment
REVISION "200402061633Z" -- 6 February 2004
DESCRIPTION "Initial Version, published as RFC xxxx."
-- RFC Editor assigns xxxx and removes this comment
::= { mib-2 9999 } -- IANA will make official assignment
-- Textual conventions defined by this memo
Dhcpv4PhysicalAddress ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1d,1d,1x:1x:1x:1x:1x:1x"
STATUS current
DESCRIPTION
"A DHCP-specific encoding of the physical address type and
physical address, intended to mirror the representation of
physical addresses in DHCP messages. The first octet of this
object contains the hardware type from the 'htype' field of
the DHCP message, the second octet of this object contains the
hardware length from the 'hlen' field, and the remaining
octets contain the hardware address from the 'chaddr' field."
REFERENCE "RFC 2131"
SYNTAX OCTET STRING (SIZE(18))
-- declare top-level MIB objects
dhcpv4Server OBJECT-IDENTITY
STATUS current
DESCRIPTION
"DHCPv4 Server MIB objects are defined in this branch."
::= { dhcp 1 }
dhcpv4ServerObjects OBJECT-IDENTITY
STATUS current
DESCRIPTION
"DHCP Server MIB server identification objects are all defined
in this branch."
::= { dhcpv4Server 1 }
dhcpv4ServerSystem OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Group of objects that are related to the overall system."
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::= { dhcpv4ServerObjects 1 }
bootpCounters OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Group of objects that count various BOOTP events."
::= { dhcpv4ServerObjects 2 }
dhcpv4Counters OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Group of objects that count various DHCPv4 events."
::= { dhcpv4ServerObjects 3 }
dhcpv4ServerConfiguration OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Objects that contain pre-configured and dynamic configuration
information."
::= { dhcpv4ServerObjects 6 }
dhcpv4ServerNotifyObjects OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Objects that are used only in notifications."
::= { dhcpv4ServerObjects 7 }
-- dhcpv4ServerSystemObjects Group
dhcpv4ServerSystemDescr 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."
::= { dhcpv4ServerSystem 1 }
dhcpv4ServerSystemObjectID 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 Ohso
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Soft, Inc. is assigned the subtree 1.3.6.1.4.1.4242, it might
assign the identifier 1.3.6.1.4.1.4242.1.1 to its Ursa DHCP
Server."
::= { dhcpv4ServerSystem 2 }
-- bootpCounterObjects Group
bootpCountRequests OBJECT-TYPE
SYNTAX Counter64
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-2131."
::= { bootpCounters 1 }
bootpCountInvalids OBJECT-TYPE
SYNTAX Counter64
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 }
bootpCountReplies OBJECT-TYPE
SYNTAX Counter64
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-2131."
::= { bootpCounters 3 }
bootpCountDroppedUnknownClients OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"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 }
bootpCountDroppedNotServingSubnet OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"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 }
-- DHCP Counters Group
dhcpv4CountDiscovers OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPDISCOVER (option 53 with value 1) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 1 }
dhcpv4CountOffers OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPOFFER (option 53 with value 2) packets
sent."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 2 }
dhcpv4CountRequests OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPREQUEST (option 53 with value 3) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 3}
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dhcpv4CountDeclines OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPDECLINE (option 53 with value 4) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 4 }
dhcpv4CountAcks OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPACK (option 53 with value 5) packets sent."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 5 }
dhcpv4CountNaks OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPNACK (option 53 with value 6) packets
sent."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 6 }
dhcpv4CountReleases OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPRELEASE (option 53 with value 7) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 7 }
dhcpv4CountInforms OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The number of DHCPINFORM (option 53 with value 8) packets
received."
REFERENCE
"RFC2131; RFC2132, section 9.6."
::= { dhcpv4Counters 8 }
dhcpv4CountForcedRenews OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCPFORCERENEW (option 53 with value 9) packets
sent."
REFERENCE
" RFC 3203, DHCP reconfigure extension."
::= { dhcpv4Counters 9 }
dhcpv4CountInvalids OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of DHCP packets received whose DHCP message type
(i.e., option number 53) is not understood or handled by the
server."
::= { dhcpv4Counters 10 }
dhcpv4CountDroppedUnknownClient OBJECT-TYPE
SYNTAX Counter64
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."
::= { dhcpv4Counters 11 }
dhcpv4CountDroppedNotServingSubnet OBJECT-TYPE
SYNTAX Counter64
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."
::= { dhcpv4Counters 12 }
-- DHCP Server Configuration
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-- dhcpv4ServerSharedNetObjects Group
dhcpv4ServerSharedNetTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dhcpv4ServerSharedNetEntry
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."
::= { dhcpv4ServerConfiguration 1 }
dhcpv4ServerSharedNetEntry OBJECT-TYPE
SYNTAX Dhcpv4ServerSharedNetEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A logical row in the dhcpv4ServerSharedNetTable."
INDEX {
dhcpv4ServerSharedNetName
}
::= { dhcpv4ServerSharedNetTable 1}
Dhcpv4ServerSharedNetEntry ::= SEQUENCE {
dhcpv4ServerSharedNetName SnmpAdminString,
dhcpv4ServerSharedNetFreeAddrLowThreshold Unsigned32,
dhcpv4ServerSharedNetFreeAddrHighThreshold Unsigned32,
dhcpv4ServerSharedNetFreeAddresses Unsigned32,
dhcpv4ServerSharedNetReservedAddresses Unsigned32,
dhcpv4ServerSharedNetTotalAddresses Unsigned32
}
dhcpv4ServerSharedNetName OBJECT-TYPE
SYNTAX SnmpAdminString (SIZE(1..100))
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The name of the shared network, which uniquely identifies an
entry in the dhcpv4ServerSharedNetTable."
::= { dhcpv4ServerSharedNetEntry 1 }
dhcpv4ServerSharedNetFreeAddrLowThreshold OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
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DESCRIPTION
"The low threshold for available free addresses in this shared
network. If the value for available free addresses in this
shared network becomes equal to or less than this value, a
dhcpv4ServerFreeAddressLow event is generated for this shared
network. No more dhcpv4ServerFreeAddressLow 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
dhcpv4ServerSharedNetFreeAddrHighThreshold."
::= { dhcpv4ServerSharedNetEntry 2 }
dhcpv4ServerSharedNetFreeAddrHighThreshold OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The high threshold for available free addresses in this
shared network. If a dhcpv4ServerFreeAddressLow event was
generated for this subnet, and the value for available free
addresses has exceeded the value of
dhcpv4ServerSubnetFreeAddrHighThreshold, then a
dhcpv4ServerFreeAddressHigh event will be generated. No more
dhcpv4ServerFreeAddressHigh 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 dhcpv4ServerSubnetFreeAddrLowThreshold."
::= { dhcpv4ServerSharedNetEntry 3 }
dhcpv4ServerSharedNetFreeAddresses OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The number of IPv4 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."
::= { dhcpv4ServerSharedNetEntry 4 }
dhcpv4ServerSharedNetReservedAddresses OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The number of IPv4 addresses which are reserved (not
available for assignment) within this shared network. If the
server does not count reserved addresses by shared network
segment, this value will be zero."
::= { dhcpv4ServerSharedNetEntry 5 }
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dhcpv4ServerSharedNetTotalAddresses OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The number of IPv4 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."
::= { dhcpv4ServerSharedNetEntry 6 }
-- dhcpv4ServerSubnetObjects Group
dhcpv4ServerSubnetTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dhcpv4ServerSubnetEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A list of subnets that are configured in this server."
::= { dhcpv4ServerConfiguration 2 }
dhcpv4ServerSubnetEntry OBJECT-TYPE
SYNTAX Dhcpv4ServerSubnetEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A logical row in the dhcpv4ServerSubnetTable."
INDEX {
dhcpv4ServerSubnetAddress
}
::= { dhcpv4ServerSubnetTable 1 }
Dhcpv4ServerSubnetEntry ::= SEQUENCE {
dhcpv4ServerSubnetAddress InetAddressIPv4,
dhcpv4ServerSubnetMask
InetAddressPrefixLength,
dhcpv4ServerSubnetSharedNetworkName SnmpAdminString,
dhcpv4ServerSubnetFreeAddrLowThreshold Unsigned32,
dhcpv4ServerSubnetFreeAddrHighThreshold Unsigned32,
dhcpv4ServerSubnetFreeAddresses Unsigned32
}
dhcpv4ServerSubnetAddress OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The IPv4 address of the subnet entry in the
dhcpv4ServerSubnetTable."
::= { dhcpv4ServerSubnetEntry 1 }
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dhcpv4ServerSubnetMask 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."
::= { dhcpv4ServerSubnetEntry 2 }
dhcpv4ServerSubnetSharedNetworkName OBJECT-TYPE
SYNTAX SnmpAdminString (SIZE(1..100))
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."
::= { dhcpv4ServerSubnetEntry 3 }
dhcpv4ServerSubnetFreeAddrLowThreshold 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
dhcpv4ServerSubnetFreeAddrLowThreshold event will be generated
for this shared network. No more
dhcpv4ServerSubnetFreeAddrLowThreshold 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
dhcpv4ServerSubnetFreeAddrHighThreshold."
::= { dhcpv4ServerSubnetEntry 4 }
dhcpv4ServerSubnetFreeAddrHighThreshold OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The high threshold for available free addresses in this
subnet. If a dhcpv4ServerSubnetFreeAddrLowThreshold event has
been generated for this subnet, and the value for available
free addresses has exceeded the value of
dhcpv4ServerSubnetFreeAddrHighThreshold, then a
dhcpv4ServerFreeAddressHigh event will be generated. No more
dhcpv4ServerFreeAddressHigh events will be generated for this
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subnet during this execution of the DHCP server until the
value for available free addresses becomes equal to or less
than the value of dhcpv4ServerSubnetFreeAddrLowThreshold."
::= { dhcpv4ServerSubnetEntry 5 }
dhcpv4ServerSubnetFreeAddresses OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The number of free IPv4 addresses which are available in this
subnet."
::= { dhcpv4ServerSubnetEntry 6 }
-- dhcpv4ServerRangeObjects Group
dhcpv4ServerRangeTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dhcpv4ServerRangeEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A list of ranges that are configured on this server."
::= { dhcpv4ServerConfiguration 3 }
dhcpv4ServerRangeEntry OBJECT-TYPE
SYNTAX Dhcpv4ServerRangeEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A logical row in the dhcpv4ServerRangeTable."
INDEX {
dhcpv4ServerRangeStartAddress,
dhcpv4ServerRangeEndAddress
}
::= { dhcpv4ServerRangeTable 1 }
Dhcpv4ServerRangeEntry ::= SEQUENCE {
dhcpv4ServerRangeStartAddress InetAddressIPv4,
dhcpv4ServerRangeEndAddress InetAddressIPv4,
dhcpv4ServerRangeSubnetMask InetAddressPrefixLength,
dhcpv4ServerRangeInUse Gauge32,
dhcpv4ServerRangeOutstandingOffers Gauge32
}
dhcpv4ServerRangeStartAddress OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
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"The IPv4 address of the first address in the range. The
value of dhcpv4ServerRangeStartAddress MUST be less than or
equal to the value of dhcpv4ServerRangeEndAddress."
::= { dhcpv4ServerRangeEntry 1 }
dhcpv4ServerRangeEndAddress OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The IPv4 address of the last address in the range. The value
of dhcpv4ServerRangeEndAddress MUST be greater than or equal
to the value of dhcpv4ServerRangeStartAddress."
::= { dhcpv4ServerRangeEntry 2 }
dhcpv4ServerRangeSubnetMask OBJECT-TYPE
SYNTAX InetAddressPrefixLength
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The subnet address mask for this range."
::= { dhcpv4ServerRangeEntry 3 }
dhcpv4ServerRangeInUse 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)."
::= { dhcpv4ServerRangeEntry 4 }
dhcpv4ServerRangeOutstandingOffers 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."
::= { dhcpv4ServerRangeEntry 5 }
-- dhcpv4ServerClientObjects Group
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dhcpv4ServerClientTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dhcpv4ServerClientEntry
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."
::= { dhcpv4ServerConfiguration 4 }
dhcpv4ServerClientEntry OBJECT-TYPE
SYNTAX Dhcpv4ServerClientEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A logical row in the dhcpv4ServerClientTable."
INDEX {
dhcpv4ServerClient
}
::= { dhcpv4ServerClientTable 1 }
Dhcpv4ServerClientEntry ::= SEQUENCE {
dhcpv4ServerClient InetAddressIPv4,
dhcpv4ServerClientSubnetMask InetAddressPrefixLength,
dhcpv4ServerClientRange InetAddressIPv4,
dhcpv4ServerClientLeaseType INTEGER,
dhcpv4ServerClientTimeRemaining Unsigned32,
dhcpv4ServerClientAllowedProtocol INTEGER,
dhcpv4ServerClientServedProtocol INTEGER,
dhcpv4ServerClientPhysicalAddress Dhcpv4PhysicalAddress,
dhcpv4ServerClientClientId OCTET STRING,
dhcpv4ServerClientHostName SnmpAdminString,
dhcpv4ServerClientDomainName SnmpAdminString
}
dhcpv4ServerClient OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The IPv4 address of this entry in the
dhcpv4ServerClientTable."
::= { dhcpv4ServerClientEntry 1 }
dhcpv4ServerClientSubnetMask OBJECT-TYPE
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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 IPv4 address, MUST be
configured on this server and appear as a row in the
dhcpSubnetTable."
::= { dhcpv4ServerClientEntry 2 }
dhcpv4ServerClientRange OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The starting IPv4 address (dhcpv4ServerRangeStartAddress
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."
::= { dhcpv4ServerClientEntry 3 }
dhcpv4ServerClientLeaseType OBJECT-TYPE
SYNTAX INTEGER {
static(1),
dynamic(2),
expired(3),
configurationReserved(4),
serverReserved(5)
}
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 IPv4 address or a DHCPDECLINE message
has been received for the IPv4 address."
::= { dhcpv4ServerClientEntry 4 }
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dhcpv4ServerClientTimeRemaining 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."
::= { dhcpv4ServerClientEntry 5 }
dhcpv4ServerClientAllowedProtocol OBJECT-TYPE
SYNTAX INTEGER {
none(1),
bootp(2),
dhcp(3),
bootpOrDhcp(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)
is reserved for BOOTP only devices, while type (3) is reserved
for DHCP only devices. A type of bootp-or-dhcp (4) can be
offered to any type of client."
::= { dhcpv4ServerClientEntry 6 }
dhcpv4ServerClientServedProtocol 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."
::= { dhcpv4ServerClientEntry 7 }
dhcpv4ServerClientPhysicalAddress OBJECT-TYPE
SYNTAX Dhcpv4PhysicalAddress
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
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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."
::= { dhcpv4ServerClientEntry 8 }
dhcpv4ServerClientClientId 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."
::= { dhcpv4ServerClientEntry 9 }
dhcpv4ServerClientHostName 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
Name part is currently limited to 255 octets. Therefore, the
sum of the string lengths for this object and the
dhcpv4ServerClientDomainName MUST be, in practice, less than
256 octets."
::= { dhcpv4ServerClientEntry 10 }
dhcpv4ServerClientDomainName 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
dhcpv4ServerClientHostName MUST be, in practice, less than 256
octets."
::= { dhcpv4ServerClientEntry 11 }
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-- dhcpv4ServerNotifyObjects Group
dhcpv4ServerNotifyDuplicateIpAddr OBJECT-TYPE
SYNTAX InetAddressIPv4
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The IPv4 address found to be a duplicate. Duplicates are
detected by servers, which issue an ICMP ECHOREQUEST prior to
offering an IPv4 address lease, or by a client issuing a
gratuitous ARP message and reported through a DHCPDECLINE
message."
::= { dhcpv4ServerNotifyObjects 1 }
dhcpv4ServerNotifyDuplicateMac OBJECT-TYPE
SYNTAX Dhcpv4PhysicalAddress
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The offending MAC address which caused a duplicate IPv4
address to be detected, if captured by the server, else 00-00-
00-00-00-00."
::= { dhcpv4ServerNotifyObjects 2 }
dhcpv4ServerNotifyClientOrServerDetected OBJECT-TYPE
SYNTAX INTEGER {
client(1),
server(2)
}
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"Duplicate IPv4 addresses can be detected either by a server,
using an ICMP ECHO message, or by a client using ARP. This
object is set by the server to (1) if the client used
DHCPDECLINE to mark the offered address as in-use, or to (2)
if the server discovered the address in use by some client
before offering it."
::= { dhcpv4ServerNotifyObjects 3 }
dhcpv4ServerNotifyServerStart OBJECT-TYPE
SYNTAX DateAndTime
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The date and time when the server began operation."
::= { dhcpv4ServerNotifyObjects 4 }
dhcpv4ServerNotifyServerStop OBJECT-TYPE
SYNTAX DateAndTime
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MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"The date and time when the server ceased operation."
::= { dhcpv4ServerNotifyObjects 5 }
-- Notifications
dhcpv4ServerNotificationPrefix OBJECT IDENTIFIER
::= { dhcpv4Server 2 }
dhcpv4ServerNotifications OBJECT IDENTIFIER
::= { dhcpv4ServerNotificationPrefix 0 }
dhcpv4ServerFreeAddressLow NOTIFICATION-TYPE
OBJECTS {
dhcpv4ServerSharedNetFreeAddrLowThreshold,
dhcpv4ServerSharedNetFreeAddresses
}
STATUS current
DESCRIPTION
"This notification signifies that the number of available IPv4
addresses for a particular shared network has fallen below the
value of dhcpv4ServerSharedNetFreeAddrLowThreshold for that
shared network."
::= { dhcpv4ServerNotifications 1 }
dhcpv4ServerFreeAddressHigh NOTIFICATION-TYPE
OBJECTS {
dhcpv4ServerSharedNetFreeAddrHighThreshold,
dhcpv4ServerSharedNetFreeAddresses
}
STATUS current
DESCRIPTION
"This notification signifies that the number of available IPv4
addresses for a particular shared network has risen above the
value of dhcpv4ServerSharedNetFreeAddrHighThreshold for that
shared network."
::= { dhcpv4ServerNotifications 2 }
dhcpv4ServerStartTime NOTIFICATION-TYPE
OBJECTS { dhcpv4ServerNotifyServerStart }
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."
::= { dhcpv4ServerNotifications 3 }
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dhcpv4ServerStopTime NOTIFICATION-TYPE
OBJECTS { dhcpv4ServerNotifyServerStop }
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."
::= { dhcpv4ServerNotifications 4 }
dhcpv4ServerDuplicateAddress NOTIFICATION-TYPE
OBJECTS {
dhcpv4ServerNotifyDuplicateIpAddr,
dhcpv4ServerNotifyDuplicateMac,
dhcpv4ServerNotifyClientOrServerDetected
}
STATUS current
DESCRIPTION
"This notification signifies that a duplicate IPv4 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
IPv4 address as unavailable for leasing to clients. The
dhcpv4ServerNotifyClientOrServerDetected object indicates
whether the client or server detected this condition."
::= { dhcpv4ServerNotifications 5 }
-- Conformance
dhcpv4ServerConformance OBJECT-IDENTITY
STATUS current
DESCRIPTION
"DHCP server conformance objects are all defined in this
branch."
::= { dhcpv4Server 3 }
dhcpv4ServerCompliances OBJECT IDENTIFIER
::= { dhcpv4ServerConformance 1 }
dhcpv4ServerGroups OBJECT IDENTIFIER
::= { dhcpv4ServerConformance 2 }
-- Compliance groups
dhcpv4ServerCompliance MODULE-COMPLIANCE
STATUS current
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DESCRIPTION
"This group describes the requirements for conformance to the
DHCP Server MIB. A DHCPv4 server implementation is only
REQUIRED to support IPv4 addresses. In particular, this
comment applies to the following objects with MAX-ACCESS not-
accessible:
dhcpv4ServerSubnet
dhcpv4ServerRangeStart
dhcpv4ServerRangeEnd
dhcpv4ServerClient."
MODULE -- this module
MANDATORY-GROUPS {
dhcpv4ServerSystemObjects,
bootpCounterObjects,
dhcpv4CounterObjects,
dhcpv4ServerSharedNetObjects,
dhcpv4ServerSubnetObjects,
dhcpv4ServerRangeObjects,
dhcpv4ServerClientObjects,
dhcpv4ServerNotifyObjectsGroup,
dhcpv4ServerNotificationsGroup
}
::= { dhcpv4ServerCompliances 1 }
-- Object groups
dhcpv4ServerSystemObjects OBJECT-GROUP
OBJECTS {
dhcpv4ServerSystemDescr,
dhcpv4ServerSystemObjectID
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpv4ServerSystemObjects group."
::= { dhcpv4ServerGroups 1 }
bootpCounterObjects OBJECT-GROUP
OBJECTS {
bootpCountRequests,
bootpCountInvalids,
bootpCountReplies,
bootpCountDroppedUnknownClients,
bootpCountDroppedNotServingSubnet
}
STATUS current
DESCRIPTION
"Objects belonging to the bootpBounterObjects group."
::= { dhcpv4ServerGroups 2 }
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dhcpv4CounterObjects OBJECT-GROUP
OBJECTS {
dhcpv4CountDiscovers,
dhcpv4CountOffers,
dhcpv4CountRequests,
dhcpv4CountDeclines,
dhcpv4CountAcks,
dhcpv4CountNaks,
dhcpv4CountReleases,
dhcpv4CountInforms,
dhcpv4CountForcedRenews,
dhcpv4CountInvalids,
dhcpv4CountDroppedUnknownClient,
dhcpv4CountDroppedNotServingSubnet
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpv4CounterObjects group."
::= { dhcpv4ServerGroups 3 }
dhcpv4ServerSharedNetObjects OBJECT-GROUP
OBJECTS {
dhcpv4ServerSharedNetFreeAddrLowThreshold,
dhcpv4ServerSharedNetFreeAddrHighThreshold,
dhcpv4ServerSharedNetFreeAddresses,
dhcpv4ServerSharedNetReservedAddresses,
dhcpv4ServerSharedNetTotalAddresses
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpv4ServerSharedNetObjects group."
::= { dhcpv4ServerGroups 4 }
dhcpv4ServerSubnetObjects OBJECT-GROUP
OBJECTS {
dhcpv4ServerSubnetMask,
dhcpv4ServerSubnetSharedNetworkName,
dhcpv4ServerSubnetFreeAddrLowThreshold,
dhcpv4ServerSubnetFreeAddrHighThreshold,
dhcpv4ServerSubnetFreeAddresses
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpv4ServerSubnetObjects group."
::= { dhcpv4ServerGroups 5 }
dhcpv4ServerRangeObjects OBJECT-GROUP
OBJECTS {
dhcpv4ServerRangeSubnetMask,
dhcpv4ServerRangeInUse,
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dhcpv4ServerRangeOutstandingOffers
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpv4ServerRangeObjects group."
::= { dhcpv4ServerGroups 6 }
dhcpv4ServerClientObjects OBJECT-GROUP
OBJECTS {
dhcpv4ServerClientSubnetMask,
dhcpv4ServerClientRange,
dhcpv4ServerClientLeaseType,
dhcpv4ServerClientTimeRemaining,
dhcpv4ServerClientAllowedProtocol,
dhcpv4ServerClientServedProtocol,
dhcpv4ServerClientPhysicalAddress,
dhcpv4ServerClientClientId,
dhcpv4ServerClientHostName,
dhcpv4ServerClientDomainName
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpv4ServerClientObjects group."
::= { dhcpv4ServerGroups 7 }
dhcpv4ServerNotifyObjectsGroup OBJECT-GROUP
OBJECTS {
dhcpv4ServerNotifyDuplicateIpAddr,
dhcpv4ServerNotifyDuplicateMac,
dhcpv4ServerNotifyClientOrServerDetected,
dhcpv4ServerNotifyServerStart,
dhcpv4ServerNotifyServerStop
}
STATUS current
DESCRIPTION
"Objects belonging to the dhcpv4ServerNotifyObjects group."
::= { dhcpv4ServerGroups 8 }
dhcpv4ServerNotificationsGroup NOTIFICATION-GROUP
NOTIFICATIONS {
dhcpv4ServerFreeAddressLow,
dhcpv4ServerFreeAddressHigh,
dhcpv4ServerStartTime,
dhcpv4ServerStopTime,
dhcpv4ServerDuplicateAddress
}
STATUS current
DESCRIPTION
"Notifications belonging to the dhcpv4ServerNotifications
group."
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::= { dhcpv4ServerGroups 9 }
END
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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. Acknowledgements
This document is the result of work undertaken by the 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 initial development of this
MIB, and to Rich Woundy for his excellent suggestions that helped
bring the work to closure.
7. IANA Considerations
IANA MUST fill in the value of the RFC number when it is assigned to
this memo. It is represented as "xxxx" in the DESCRIPTION section
of MODULE-IDENTITY.
One specific value for a MIB object requires completion before this
memo can advance to RFC status. It is:
o OID value for "dhcp" -- see MODULE-IDENTITY
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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.
Therefore, if this MIB is implemented correctly, there is no risk
that an intruder can alter or create any management objects of this
MIB via direct SNMP SET operations.
Some of the readable objects in this MIB module (i.e., objects with
a MAX-ACCESS other than not-accessible) may be considered sensitive
or vulnerable in some network environments. It is thus important to
control even GET and/or NOTIFY access to these objects and possibly
to even encrypt the values of these objects when sending them over
the network via SNMP. These are the tables and objects and their
sensitivity/vulnerability:
o dhcpv4ServerRangeTable
o dhcpv4ServerClientTable
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 IPv4 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 IPv4 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.
SNMP versions prior to SNMPv3 did not include adequate security.
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 (see [RFC3410], section
8), including full support for the SNMPv3 cryptographic mechanisms
(for authentication and privacy).
Further, deployment of SNMP versions prior to SNMPv3 is NOT
RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to
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Internet Draft DHCPv4 Server MIB February 2004
enable cryptographic security. It is then a customer/operator
responsibility to ensure that the SNMP entity giving access to an
instance of this MIB module 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
One normative reference is currently an Internet-Draft, nearly ready
for Working Group Last Call. This reference MUST be updated when
the draft advances to RFC status.
9.1. Normative References
[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.
[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
9.2. Informative References
[RFC1123] R. Braden, "Requirements for Internet Hosts -- Application
and Support," RFC 1123, October 1989.
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Internet Draft DHCPv4 Server MIB February 2004
[RFC3410] Case, J., Mundy, R., Partain, D. and B. Stewart,
"Introduction and Applicability Statements for Internet-Standard
Management Framework", RFC 3410, December 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
11. Full Copyright Statement
Copyright (C), 2004, The Internet Society. All Rights Reserved.
This document and translations of it may be copied and furnished to
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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
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Internet Draft DHCPv4 Server MIB February 2004
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.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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