Network Working Group F. Baker Request for Comments: 2096 Cisco Systems Obsoletes: 1354 January 1997 Category: Standards Track
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
1. Introduction
2. The SNMP Network Management Framework
2.1 Object Definitions
3. Overview
4. Definitions
5. Acknowledgements
6. References
7. Security Considerations
8. Author's Address
This memo defines an update to RFC 1354, "IP Forwarding Table MIB",
for Classless Inter-Domain Routing (CIDR). That document was
developed by the Router Requirements Working Group as an update to
RFC 1213's ipRouteTable, with the display of multiple routes as
a primary objective. The significant difference between this MIB and
RFC 1354 is the recognition (explicitly discussed but by consensus
left to future work) that CIDR routes may have the
same network number but different network masks. Note that this MIB
obsoletes a number of objects from RFC 1354. The reader should pay
careful attention to the STATUS field.
The SNMP Network Management Framework presently consists of three major components. They are:
Textual conventions are defined in RFC 1903 [3], and conformance statements are defined in RFC 1904 [5].
The Framework permits new objects to be defined for the purpose of experimentation and evaluation.
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. Objects in the MIB
are defined using the subset of Abstract Syntax Notation One (ASN.1)
defined in the SMI. In particular, each object object type is named
by an OBJECT IDENTIFIER, an administratively assigned name. The
object type together with an object instance serves to uniquely
identify a specific instantiation of the object. For
human convenience, we often use a textual string, termed the
descriptor, to refer to the object type.
The MIB consists of two tables and two global objects.
(1) The object ipForwardNumber indicates the number of
current routes. This is primarily to avoid having to
read the table in order to determine this number.
(2) The ipForwardTable updates the RFC 1213 ipRouteTable to display multipath IP Routes. This is in turn obsoleted by the ipCidrRouteTable.
(3) The ipCidrRouteTable updates the RFC 1213 ipRouteTable to
display multipath IP Routes having the same network
number but differing network masks.
LAST-UPDATED "9609190000Z" -- Thu Sep 26 16:34:47 PDT 1996 ORGANIZATION "IETF OSPF Working Group" CONTACT-INFO " Fred Baker Postal: Cisco Systems 519 Lado Drive Santa Barbara, California 93111
Phone: +1 805 681 0115
Email: fred@cisco.com
"
DESCRIPTION
"The MIB module for the display of CIDR multipath IP Routes."
REVISION "9609190000Z" DESCRIPTION "Revisions made by the OSPF WG." ::= { ip 24 }
SYNTAX Gauge32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of current ipCidrRouteTable entries that are not invalid." ::= { ipForward 3 }
SYNTAX SEQUENCE OF IpCidrRouteEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This entity's IP Routing table." REFERENCE "RFC 1213 Section 6.6, The IP Group" ::= { ipForward 4 }
SYNTAX IpCidrRouteEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A particular route to a particular destina- tion, under a particular policy." INDEX { ipCidrRouteDest, ipCidrRouteMask, ipCidrRouteTos, ipCidrRouteNextHop } ::= { ipCidrRouteTable 1 }
Integer32,
ipCidrRouteMetric1
Integer32,
ipCidrRouteMetric2
Integer32,
ipCidrRouteMetric3
Integer32,
ipCidrRouteMetric4
Integer32,
ipCidrRouteMetric5
Integer32,
ipCidrRouteStatus
RowStatus
}
SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The destination IP address of this route.
This object may not take a Multicast (Class D)
address value.
Any assignment (implicit or otherwise) of an
instance of this object to a value x must be
rejected if the bitwise logical-AND of x with
the value of the corresponding instance of the
ipCidrRouteMask object is not equal to x."
::= { ipCidrRouteEntry 1 }
SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "Indicate the mask to be logical-ANDed with the destination address before being compared to the value in the ipCidrRouteDest field. For those systems that do not support arbitrary subnet masks, an agent constructs the value of the ipCidrRouteMask by reference to the IP Ad- dress Class.
Any assignment (implicit or otherwise) of an
instance of this object to a value x must be
rejected if the bitwise logical-AND of x with
the value of the corresponding instance of the
ipCidrRouteDest object is not equal to ipCidrRoute-
Dest."
::= { ipCidrRouteEntry 2 }
SYNTAX Integer32 MAX-ACCESS read-only STATUS current DESCRIPTION "The policy specifier is the IP TOS Field. The encoding of IP TOS is as specified by the following convention. Zero indicates the default path if no more specific policy applies. +-----+-----+-----+-----+-----+-----+-----+-----+ | | | | | PRECEDENCE | TYPE OF SERVICE | 0 | | | | | +-----+-----+-----+-----+-----+-----+-----+-----+ IP TOS IP TOS Field Policy Field Policy Contents Code Contents Code 0 0 0 0 ==> 0 0 0 0 1 ==> 2 0 0 1 0 ==> 4 0 0 1 1 ==> 6 0 1 0 0 ==> 8 0 1 0 1 ==> 10 0 1 1 0 ==> 12 0 1 1 1 ==> 14 1 0 0 0 ==> 16 1 0 0 1 ==> 18 1 0 1 0 ==> 20 1 0 1 1 ==> 22 1 1 0 0 ==> 24 1 1 0 1 ==> 26 1 1 1 0 ==> 28 1 1 1 1 ==> 30" ::= { ipCidrRouteEntry 3 }
SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "On remote routes, the address of the next sys- tem en route; Otherwise, 0.0.0.0."
::= { ipCidrRouteEntry 4 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS current DESCRIPTION "The ifIndex value which identifies the local interface through which the next hop of this route should be reached." DEFVAL { 0 } ::= { ipCidrRouteEntry 5 }
SYNTAX INTEGER { other (1), -- not specified by this MIB reject (2), -- route which discards traffic local (3), -- local interface remote (4) -- remote destination } MAX-ACCESS read-create STATUS current DESCRIPTION "The type of route. Note that local(3) refers to a route for which the next hop is the final destination; remote(4) refers to a route for which the next hop is not the final destina- tion.
Routes which do not result in traffic forwarding or
rejection should not be displayed even if the
implementation keeps them stored internally.
reject (2) refers to a route which, if matched, discards
the message as unreachable. This is used in some
protocols as a means of correctly aggregating routes."
::= { ipCidrRouteEntry 6 }
SYNTAX INTEGER { other (1), -- not specified local (2), -- local interface netmgmt (3), -- static route icmp (4), -- result of ICMP Redirect -- the following are all dynamic -- routing protocols
egp (5), -- Exterior Gateway Protocol ggp (6), -- Gateway-Gateway Protocol hello (7), -- FuzzBall HelloSpeak rip (8), -- Berkeley RIP or RIP-II isIs (9), -- Dual IS-IS esIs (10), -- ISO 9542 ciscoIgrp (11), -- Cisco IGRP bbnSpfIgp (12), -- BBN SPF IGP ospf (13), -- Open Shortest Path First bgp (14), -- Border Gateway Protocol idpr (15), -- InterDomain Policy Routing ciscoEigrp (16) -- Cisco EIGRP } MAX-ACCESS read-only STATUS current DESCRIPTION "The routing mechanism via which this route was learned. Inclusion of values for gateway rout- ing protocols is not intended to imply that hosts should support those protocols." ::= { ipCidrRouteEntry 7 }
SYNTAX Integer32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of seconds since this route was last updated or otherwise determined to be correct. Note that no semantics of `too old' can be implied except through knowledge of the routing protocol by which the route was learned." DEFVAL { 0 } ::= { ipCidrRouteEntry 8 }
SYNTAX OBJECT IDENTIFIER MAX-ACCESS read-create STATUS current DESCRIPTION "A reference to MIB definitions specific to the particular routing protocol which is responsi- ble for this route, as determined by the value specified in the route's ipCidrRouteProto value. If this information is not present, its value should be set to the OBJECT IDENTIFIER { 0 0 }, which is a syntactically valid object identif-
ier, and any implementation conforming to ASN.1
and the Basic Encoding Rules must be able to
generate and recognize this value."
::= { ipCidrRouteEntry 9 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS current DESCRIPTION "The Autonomous System Number of the Next Hop. The semantics of this object are determined by the routing-protocol specified in the route's ipCidrRouteProto value. When this object is unknown or not relevant its value should be set to zero." DEFVAL { 0 } ::= { ipCidrRouteEntry 10 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS current DESCRIPTION "The primary routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipCidrRouteProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipCidrRouteEntry 11 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS current DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipCidrRouteProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipCidrRouteEntry 12 }
SYNTAX Integer32 MAX-ACCESS read-create
STATUS current DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipCidrRouteProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipCidrRouteEntry 13 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS current DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipCidrRouteProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipCidrRouteEntry 14 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS current DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipCidrRouteProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipCidrRouteEntry 15 }
SYNTAX RowStatus MAX-ACCESS read-create STATUS current DESCRIPTION "The row status variable, used according to row installation and removal conventions." ::= { ipCidrRouteEntry 16 }
MODULE -- this module
MANDATORY-GROUPS { ipForwardCidrRouteGroup }
::= { ipForwardCompliances 1 }
::= { ipForwardGroups 3 }
SYNTAX Gauge32 MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The number of current ipForwardTable entries that are not invalid." ::= { ipForward 1 }
SYNTAX SEQUENCE OF IpForwardEntry MAX-ACCESS not-accessible STATUS obsolete DESCRIPTION "This entity's IP Routing table." REFERENCE "RFC 1213 Section 6.6, The IP Group" ::= { ipForward 2 }
SYNTAX IpForwardEntry MAX-ACCESS not-accessible STATUS obsolete DESCRIPTION "A particular route to a particular destina- tion, under a particular policy." INDEX { ipForwardDest, ipForwardProto, ipForwardPolicy, ipForwardNextHop } ::= { ipForwardTable 1 }
Integer32,
ipForwardMetric1
Integer32,
ipForwardMetric2
Integer32,
ipForwardMetric3
Integer32,
ipForwardMetric4
Integer32,
ipForwardMetric5
Integer32
}
SYNTAX IpAddress MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The destination IP address of this route. An entry with a value of 0.0.0.0 is considered a default route.
This object may not take a Multicast (Class D)
address value.
Any assignment (implicit or otherwise) of an
instance of this object to a value x must be
rejected if the bitwise logical-AND of x with
the value of the corresponding instance of the
ipForwardMask object is not equal to x."
::= { ipForwardEntry 1 }
SYNTAX IpAddress MAX-ACCESS read-create STATUS obsolete DESCRIPTION "Indicate the mask to be logical-ANDed with the destination address before being compared to the value in the ipForwardDest field. For those systems that do not support arbitrary subnet masks, an agent constructs the value of the ipForwardMask by reference to the IP Ad- dress Class.
Any assignment (implicit or otherwise) of an
instance of this object to a value x must be
rejected if the bitwise logical-AND of x with
the value of the corresponding instance of the
ipForwardDest object is not equal to ipForward-
Dest."
DEFVAL { '00000000'h } -- 0.0.0.0 ::= { ipForwardEntry 2 }
SYNTAX Integer32 MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The general set of conditions that would cause the selection of one multipath route (set of next hops for a given destination) is referred to as 'policy'.
Unless the mechanism indicated by ipForwardPro-
to specifies otherwise, the policy specifier is
the IP TOS Field. The encoding of IP TOS is as
specified by the following convention. Zero
indicates the default path if no more specific
policy applies.
+-----+-----+-----+-----+-----+-----+-----+-----+ | | | | | PRECEDENCE | TYPE OF SERVICE | 0 | | | | | +-----+-----+-----+-----+-----+-----+-----+-----+ IP TOS IP TOS Field Policy Field Policy Contents Code Contents Code 0 0 0 0 ==> 0 0 0 0 1 ==> 2 0 0 1 0 ==> 4 0 0 1 1 ==> 6 0 1 0 0 ==> 8 0 1 0 1 ==> 10 0 1 1 0 ==> 12 0 1 1 1 ==> 14 1 0 0 0 ==> 16 1 0 0 1 ==> 18 1 0 1 0 ==> 20 1 0 1 1 ==> 22 1 1 0 0 ==> 24 1 1 0 1 ==> 26 1 1 1 0 ==> 28 1 1 1 1 ==> 30
Protocols defining 'policy' otherwise must ei-
ther define a set of values which are valid for
this object or must implement an integer-
instanced policy table for which this object's
value acts as an index."
::= { ipForwardEntry 3 }
SYNTAX IpAddress MAX-ACCESS read-only STATUS obsolete DESCRIPTION "On remote routes, the address of the next sys- tem en route; Otherwise, 0.0.0.0." ::= { ipForwardEntry 4 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS obsolete DESCRIPTION "The ifIndex value which identifies the local interface through which the next hop of this route should be reached." DEFVAL { 0 } ::= { ipForwardEntry 5 }
SYNTAX INTEGER { other (1), -- not specified by this MIB invalid (2), -- logically deleted local (3), -- local interface remote (4) -- remote destination } MAX-ACCESS read-create STATUS obsolete DESCRIPTION "The type of route. Note that local(3) refers to a route for which the next hop is the final destination; remote(4) refers to a route for which the next hop is not the final destina- tion.
Setting this object to the value invalid(2) has
the effect of invalidating the corresponding
entry in the ipForwardTable object. That is,
it effectively disassociates the destination
identified with said entry from the route iden-
tified with said entry. It is an implementation-specific matter as to whether the agent removes an invalidated entry from the table. Accordingly, management stations must be prepared to receive tabular information from agents that corresponds to entries not current- ly in use. Proper interpretation of such en- tries requires examination of the relevant ip- ForwardType object." DEFVAL { invalid } ::= { ipForwardEntry 6 }
SYNTAX INTEGER { other (1), -- not specified local (2), -- local interface netmgmt (3), -- static route icmp (4), -- result of ICMP Redirect -- the following are all dynamic -- routing protocols egp (5), -- Exterior Gateway Protocol ggp (6), -- Gateway-Gateway Protocol hello (7), -- FuzzBall HelloSpeak rip (8), -- Berkeley RIP or RIP-II is-is (9), -- Dual IS-IS es-is (10), -- ISO 9542 ciscoIgrp (11), -- Cisco IGRP bbnSpfIgp (12), -- BBN SPF IGP ospf (13), -- Open Shortest Path First bgp (14), -- Border Gateway Protocol idpr (15) -- InterDomain Policy Routing } MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The routing mechanism via which this route was learned. Inclusion of values for gateway rout- ing protocols is not intended to imply that hosts should support those protocols." ::= { ipForwardEntry 7 }
SYNTAX Integer32 MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The number of seconds since this route was
last updated or otherwise determined to be
correct. Note that no semantics of `too old'
can be implied except through knowledge of the
routing protocol by which the route was learned." DEFVAL { 0 } ::= { ipForwardEntry 8 }
SYNTAX OBJECT IDENTIFIER MAX-ACCESS read-create STATUS obsolete DESCRIPTION "A reference to MIB definitions specific to the particular routing protocol which is responsi- ble for this route, as determined by the value specified in the route's ipForwardProto value. If this information is not present, its value should be set to the OBJECT IDENTIFIER { 0 0 }, which is a syntactically valid object identif- ier, and any implementation conforming to ASN.1 and the Basic Encoding Rules must be able to generate and recognize this value." ::= { ipForwardEntry 9 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS obsolete DESCRIPTION "The Autonomous System Number of the Next Hop. When this is unknown or not relevant to the protocol indicated by ipForwardProto, zero." DEFVAL { 0 } ::= { ipForwardEntry 10 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS obsolete DESCRIPTION "The primary routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipForwardProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipForwardEntry 11 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS obsolete DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipForwardProto value. If this metric is not used, its value should be set to -1."
DEFVAL { -1 }
::= { ipForwardEntry 12 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS obsolete DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipForwardProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipForwardEntry 13 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS obsolete DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's ipForwardProto value. If this metric is not used, its value should be set to -1." DEFVAL { -1 } ::= { ipForwardEntry 14 }
SYNTAX Integer32 MAX-ACCESS read-create STATUS obsolete DESCRIPTION "An alternate routing metric for this route. The semantics of this metric are determined by the routing-protocol specified in the route's
ipForwardProto value. If this metric is not
used, its value should be set to -1."
DEFVAL { -1 }
::= { ipForwardEntry 15 }
MODULE -- this module
MANDATORY-GROUPS { ipForwardMultiPathGroup }
::= { ipForwardCompliances 2 }
::= { ipForwardGroups 2 }
This work was originally performed by the Router Requirements Working Group at the request of the OSPF Working Group. This update was performed under the auspices of the OSPF Working Group. John Moy of Proteon Incorporated is the chair.
Security is an objective not in this MIB view.
Fred Baker
Cisco Systems
519 Lado Drive
Santa Barbara, California 93111
Phone: +1 805 681 0115
EMail: fred@cisco.com