Network Working Group Barr Hibbs INTERNET-DRAFT (no affiliation) Category: Standards Track Glenn Waters Nortel Networks February 2002 Dynamic Host Configuration Protocol (DHCP) Server MIB Saved Thursday, February 14, 2002, 11:26:01 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. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 1] Internet Draft DHCP Server MIB February 2002 Table of Contents 1. Introduction...................................................2 2. Overview.......................................................3 2.1. Relationship to Other MIBs.................................4 2.1.1. DHCP MIB Extensions...................................4 2.1.2. Host System MIB Extensions............................4 2.1.3. DHCPv6 Server MIB Extensions..........................4 2.1.4. DHCP Client MIB Extensions............................5 2.1.5. DHCP Relay Agent MIB Extensions.......................5 2.2. Textual Conventions Introduced in this MIB.................5 2.2.1. DhcpTimeInterval......................................5 2.2.2. HardwareAddressType...................................5 2.2.3. HardwareAddressLength.................................5 2.2.4. MacAddress............................................5 2.2.5. PhysicalAddress.......................................5 2.2.6. DhcpLabel.............................................6 2.3. BOOTP and DHCP Counter Groups..............................6 2.4. BOOTP and DHCP Optional Statistics Group...................6 2.5. Response Times and ICMP Echo...............................8 3. Definitions....................................................8 4. Intellectual Property.........................................39 5. Notes.........................................................40 5.1. Issues....................................................40 5.2. Changes from Prior Drafts.................................41 6. Acknowledgements..............................................42 7. Security Considerations.......................................42 8. References....................................................43 9. Editors' Addresses............................................44 10. Full Copyright Statement.....................................44 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 2.1.] 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. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 2] Internet Draft DHCP Server MIB February 2002 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. 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 2.3 through 2.5 are not meant to be comprehensive but are illustrative of the potential uses of the objects defined by this MIB. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 3] Internet Draft DHCP Server MIB February 2002 2.1. Relationship to Other MIBs 2.1.1. DHCP MIB Extensions The DHCP MIB extensions will 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. 2.1.2. 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. 2.1.3. 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. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 4] Internet Draft DHCP Server MIB February 2002 2.1.4. 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. 2.1.5. 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. 2.2. Textual Conventions Introduced in this MIB Severaal 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. 2.2.1. DhcpTimeInterval This data type measures time intervals since the beginning of some epoch in milliseconds. 2.2.2. HardwareAddressType This data type contains the type of hardware address represented by MacAddress, as defined for ARP messages. 2.2.3. HardwareAddressLength The length in octets of MacAddress is contained in this type. 2.2.4. MacAddress The actual layer 1 hardware address is contained in this data type. 2.2.5. PhysicalAddress This data type combines the hardware type octet with the length and hardware (NIC or MAC) address to produce a unique address type. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 5] Internet Draft DHCP Server MIB February 2002 2.2.6. DhcpLabel This data type contains labels used as identifiers by DHCP servers. 2.3. 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. 2.4. 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. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 6] Internet Draft DHCP Server MIB February 2002 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; Hibbs & Waters Expires: Feb 2002 + 6 months [Page 7] Internet Draft DHCP Server MIB February 2002 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. 2.5. 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. 3. 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, IpAddress FROM SNMPv2-SMI TEXTUAL-CONVENTION, RowStatus, DisplayString, TruthValue, DateAndTime FROM SNMPv2-TC MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP Hibbs & Waters Expires: Feb 2002 + 6 months [Page 8] Internet Draft DHCP Server MIB February 2002 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 LAST-UPDATED "2002-02-14 11:26" ORGANIZATION "IETF DHC Working Group" 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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 9] Internet Draft DHCP Server MIB February 2002 "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 "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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 10] Internet Draft DHCP Server MIB February 2002 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...]" 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 DisplayString (SIZE (1..100)) DISPLAY-HINT STATUS current DESCRIPTION Hibbs & Waters Expires: Feb 2002 + 6 months [Page 11] Internet Draft DHCP Server MIB February 2002 -- serverSystem Group serverSystemDescr OBJECT-TYPE SYNTAX DisplayString (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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 12] Internet Draft DHCP Server MIB February 2002 "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*/ dhcpCountLeaseQueries OBJECT-TYPE -- /*new*/ SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of DHCPLEASEQUERY (option 53 with value TBD) packets received." REFERENCE "draft-ietf-dhc-leasequery-02.txt." ::= { dhcpCounters 6 } -- /*new*/ Hibbs & Waters Expires: Feb 2002 + 6 months [Page 13] Internet Draft DHCP Server MIB February 2002 -- 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 11 } -- /*renumbered*/ dhcpCountAcks OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of DHCPACK (option 53 with value 5) packets sent." REFERENCE "RFC2131; RFC2132, section 9.6." ::= { dhcpCounters 12 } -- /*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 13 } -- /*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 14 } -- /*new*/ dhcpCountKnowns OBJECT-TYPE -- /*new*/ SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION Hibbs & Waters Expires: Feb 2002 + 6 months [Page 14] Internet Draft DHCP Server MIB February 2002 "The number of DHCPKNOWN (option 53 with value TBD) packets sent." REFERENCE "draft-ietf-dhc-leasequery-02.txt." ::= { dhcpCounters 12 } -- /*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-02.txt." ::= { dhcpCounters 13 } -- /*new*/ -- DHCP packet error counters dhcpCountInvalids OBJECT-TYPE SYNTAX Counter32 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." ::= { dhcpCounters 17 } -- /*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 18 } -- /*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 19 } -- /*renumbered*/ Hibbs & Waters Expires: Feb 2002 + 6 months [Page 15] Internet Draft DHCP Server MIB February 2002 -- 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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 16] Internet Draft DHCP Server MIB February 2002 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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 17] Internet Draft DHCP Server MIB February 2002 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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 18] Internet Draft DHCP Server MIB February 2002 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 "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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 19] Internet Draft DHCP Server MIB February 2002 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 "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." Hibbs & Waters Expires: Feb 2002 + 6 months [Page 20] Internet Draft DHCP Server MIB February 2002 ::= { 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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 21] Internet Draft DHCP Server MIB February 2002 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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 22] Internet Draft DHCP Server MIB February 2002 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 "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 { Hibbs & Waters Expires: Feb 2002 + 6 months [Page 23] Internet Draft DHCP Server MIB February 2002 serverSubnet IpAddress, serverSubnetMask IpAddress, serverSubnetSharedNetworkName DhcpLabel,-- /*modified*/ serverSubnetFreeAddressLowThreshold Unsigned32, serverSubnetFreeAddressHighThreshold Unsigned32, ServerSubnetFreeAddresses Unsigned32 -- /*renamed*/ } serverSubnet OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only-- /*changed*/ STATUS current DESCRIPTION "The IP address of the subnet." ::= { serverSubnetEntry 1 } serverSubnetMask OBJECT-TYPE SYNTAX IpAddress 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 } 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." Hibbs & Waters Expires: Feb 2002 + 6 months [Page 24] Internet Draft DHCP Server MIB February 2002 ::= { 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 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 IpAddress, serverRangeEnd IpAddress, serverRangeSubnetMask IpAddress, serverRangeInUse Gauge32, serverRangeOutstandingOffers Gauge32 } serverRangeStart OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only Hibbs & Waters Expires: Feb 2002 + 6 months [Page 25] Internet Draft DHCP Server MIB February 2002 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 IpAddress 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 IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The subnet address mask for this range." ::= { serverRangeEntry 3 } 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 } Hibbs & Waters Expires: Feb 2002 + 6 months [Page 26] Internet Draft DHCP Server MIB February 2002 -- 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." ::= { serverAddressTable 1 } ServerAddressEntry ::= SEQUENCE { serverAddress IpAddress, serverAddressSubnetMask IpAddress, serverAddressRange IpAddress, serverAddressType INTEGER, serverAddressTimeRemaining Unsigned32, serverAddressAllowedProtocol INTEGER, serverAddressServedProtocol INTEGER, serverAddressMacAddress OCTET STRING, serverAddressClientId OCTET STRING, serverAddressHostName DisplayString, serverAddressDomainName DisplayString } serverAddress OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS not-accessible STATUS current DESCRIPTION "The IP address of the entry." ::= { serverAddressEntry 1 } serverAddressSubnetMask OBJECT-TYPE SYNTAX IpAddress Hibbs & Waters Expires: Feb 2002 + 6 months [Page 27] Internet Draft DHCP Server MIB February 2002 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 IpAddress 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), 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 28] Internet Draft DHCP Server MIB February 2002 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 } 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." Hibbs & Waters Expires: Feb 2002 + 6 months [Page 29] Internet Draft DHCP Server MIB February 2002 ::= { 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 DisplayString (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 serverAddressDomainName must, in practice, be less than 256 octets." ::= { serverAddressEntry 10 } serverAddressDomainName OBJECT-TYPE SYNTAX DisplayString (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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 30] Internet Draft DHCP Server MIB February 2002 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 one hour time period before removing that entry from this table." ::= { serverClientTable 1 } ServerClientEntry ::= SEQUENCE { serverClientHardwareAddress PhysicalAddress serverClientSubnetMask IpAddress, serverClientAddress IpAddress, 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 } serverClientSubnetMask OBJECT-TYPE Hibbs & Waters Expires: Feb 2002 + 6 months [Page 31] Internet Draft DHCP Server MIB February 2002 SYNTAX IpAddress MAX-ACCESS not-accessible STATUS current DESCRIPTION "The subnet mask (DHCP option 1) applied to serverClientAddress." ::= { serverClientEntry 2 } serverClientAddress OBJECT-TYPE SYNTAX IpAddress 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 3 } serverClientLastRequestTime OBJECT-TYPE SYNTAX DhcpTimeInterval MAX-ACCESS read-only STATUS current DESCRIPTION "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 { Hibbs & Waters Expires: Feb 2002 + 6 months [Page 32] Internet Draft DHCP Server MIB February 2002 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 IpAddress 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 IpAddress 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." Hibbs & Waters Expires: Feb 2002 + 6 months [Page 33] Internet Draft DHCP Server MIB February 2002 ::= { 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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 34] Internet Draft DHCP Server MIB February 2002 "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 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 35] Internet Draft DHCP Server MIB February 2002 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 } 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, Hibbs & Waters Expires: Feb 2002 + 6 months [Page 36] Internet Draft DHCP Server MIB February 2002 dhcpCountInforms, dhcpCountInvalids, dhcpCountOffers, dhcpCountAcks, dhcpCountNacks, dhcpCountDroppedUnknownClient, dhcpCountDroppedNotServingSubnet } STATUS current DESCRIPTION "Objects belonging to the dhcpCountersGroup." ::= { serverMIBGroups 3 } bootpOptionalStatisticsGroup OBJECT-GROUP OBJECTS { 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, Hibbs & Waters Expires: Feb 2002 + 6 months [Page 37] Internet Draft DHCP Server MIB February 2002 serverRangeStart, serverRangeEnd, serverRangeSubnetMask, serverRangeInUse, serverRangeOutstandingOffers, serverAddress, serverAddressSubnetMask, serverAddressRange, serverAddressType, serverAddressTimeRemaining, serverAddressAllowedProtocol, serverAddressServedProtocol, serverAddressHardwareAddress, serverAddressClientId, serverAddressHostName, 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, Hibbs & Waters Expires: Feb 2002 + 6 months [Page 38] Internet Draft DHCP Server MIB February 2002 serverNotifyDuplicateMAC, serverNotifyClientDuplicateMAC, serverNotifyClientDuplicateIP, serverNotifyContestedIpAddress } STATUS current DESCRIPTION "DHCP Server MIB objects used in notifications." ::= { serverMIBGroups 9 } serverNotificationsGroup NOTIFICATION-GROUP NOTIFICATIONS { serverFreeAddressLow, serverFreeAddressHigh, serverServerStart, serverServerStop, serverDNSQueueTooBig, serverOtherServerNotResponding, serverDuplicateAddress, serverAddressConflict, serverOtherServerResponding, serverFailoverConfigMismatch } STATUS current DESCRIPTION "Notifications that are implemented by the DHCP Server agent." ::= { serverMIBGroups 10 } END 4. 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. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 39] Internet Draft DHCP Server MIB February 2002 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. 5. Notes This section will be removed when this memo goes to Working Group Last Call. 5.1. 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 Hibbs & Waters Expires: Feb 2002 + 6 months [Page 40] Internet Draft DHCP Server MIB February 2002 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? 5.2. 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 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 authorĘs 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" Hibbs & Waters Expires: Feb 2002 + 6 months [Page 41] Internet Draft DHCP Server MIB February 2002 version as well as some unintentionally omitted text for serverNotifyObjects. The "-07" version 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. Because of an error posting the ū07 draft to the editor's queue it was not accepted in time for IETF-52 and is being submitted to the Internet-Drafts editor with one change identified by Alan Hackert. Finally, some of the initial text was brought in line with standard requirements for Internet-Drafts. 6. 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 Ryan Troll, Nathan Lane, Kim Kinnear, Yannick Koehler, Nathan Lane, Rick Geesen, Jin Tao, James Brister, and Alan Hackert for their review, comments, and contributions. 7. 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. SNMPv1 by itself is not a secure environment. Even if the network itself is secure (for example by using IPSEC), 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. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 42] Internet Draft DHCP Server MIB February 2002 SNMPv2 communities provide a minimal level of access control, but 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 [RFC2274] and the View-based Access Control Model [RFC2275] 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. 8. 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. [RFC2287] Krupczak, R., and J. Saperia, "Definitions of System-Level Managed Objects for Applications," RFC 2287, February 1998. [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. [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. Hibbs & Waters Expires: Feb 2002 + 6 months [Page 43] Internet Draft DHCP Server MIB February 2002 [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. , Yves T'Joens and Christian Hublet, Peter De Schrijver, "The DHCP Reconfigure Extension," July 2001 , Rich Woundy and Kim Kinnear, "DHCP Lease Query," July 2001 9. 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 10. Full Copyright Statement Copyright (C) The Internet Society, 2002.All Rights Reserved. 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