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Cisco's implementation of the Internet Protocol (IP) suite provides all major services contained in the TCP/IP specifications.
Use the commands in this chapter to configure and monitor the IP routing protocols. For IP routing protocol configuration information and examples, refer to the "Configuring IP Routing Protocols" chapter of the Router Products Configuration Guide.
Use the aggregate-address router configuration command to create an aggregate entry in a BGP routing table. Use the no form of this command to disable this feature.
aggregate-address address mask [as-set] [summary-only] [suppress-map map-name]
address | Aggregate address. |
mask | Aggregate mask. |
as-set | (Optional) Generates autonomous system set path information. |
summary-only | (Optional) Filters more specific routes from updates. |
suppress-map map-name | (Optional) Name of route-map to suppress. |
Disabled
Router configuration
You can implement aggregate routing in BGP either by redistributing an aggregate route into BGP or by using this conditional aggregate routing feature.
Using the aggregate-address command with no arguments will create an aggregate entry in the BGP routing table if there are any more-specific routes available that fall in the specified range. The aggregate route will be advertised as coming from your autonomous system and has the atomic aggregate attribute set to show that information might be missing. (By default, the atomic aggregate attribute is set unless you specify the as-set keyword in the aggregate-address command.)
Using the as-set keyword creates an aggregate entry using the same rules that the command follows without this keyword, but the path advertised for this route will be an AS_SET consisting of all elements contained in all paths that are being summarized. Do not use this form of aggregate-address when aggregating many paths, because this route must be continually withdrawn and re-updated as autonomous system path reachability information for the summarized routes changes.
Using the summary-only keyword not only creates the aggregate route (for example, 193.*.*.*) but will also suppress advertisements of more specific routes to all neighbors. If you only want to suppress advertisements to certain neighbors, you may use the neighbor distribute-list command, with caution. If a more-specific route leaks out, all BGP speakers will prefer that route over the less- specific aggregate you are generating (using longest-match routing).
Using the suppress-map keyword creates the aggregate route but suppresses advertisement of specified route maps. You can use the match clauses of route maps to selectively suppress some more specific routes of the aggregate and leave others unsuppressed. IP access lists and AS path access lists match clauses are supported.
In the following example, an aggregate address is created. The path advertised for this route will be an AS_SET consisting of all elements contained in all paths that are being summarized.
router bgp 5aggregate-address 193.0.0.0 255.0.0.0 as-set
match ip address
match as-path
route-map
area-id | Identifier of the area for which authentication is to be enabled. The identifier can be specified as either a decimal value or an IP address. |
Type 0 authentication (no authentication)
Router configuration
Specifying authentication for an area sets the authentication to Type 1 (simple password) as specified in RFC 1247. If this command is not included in the configuration file, authentication of Type 0 (no authentication) is assumed.
The authentication type must be the same for all routers in an area. The authentication password for all OSPF routers on a network must be the same if they are to communicate with each other via OSPF. Use the ip ospf authentication-key interface configuration command to specify this password.
The following example mandates authentication for areas 0 and 36.0.0.0 of OSPF routing process 201. Authentication keys are also provided.
interface ethernet 0 ip address 131.119.251.201 255.255.255.0 ip ospf authentication-key adcdefgh ! interface ethernet 1 ip address 36.56.0.201 255.255.0.0 ip ospf authentication-key ijklmnop ! router ospf 201 network 36.0.0.0 0.255.255.255 area 36.0.0.0 network 131.119.0.0 0.0.255.255 area 0 area 36.0.0.0 authentication area 0 authentication
area default-cost
area stub
ip ospf authentication-key
area-id | Identifier for the stub area. The identifier can be specified as either a decimal value or as an IP address. |
cost | Cost for the default summary route used for a stub area. The acceptable value is a 24-bit number. |
Cost of 1
Router configuration
This command is used only on an area border router attached to a stub area.
There are two stub area router configuration commands: the stub and default-cost options of the area command. In all routers attached to the stub area, the area should be configured as a stub area using the stub option of the area command. Use the default-cost option only on an area border router attached to the stub area. The default-cost option provides the metric for the summary default route generated by the area border router into the stub area.
The following example assigns a default-cost of 20 to stub network 36.0.0.0:
interface ethernet 0 ip address 36.56.0.201 255.255.0.0 ! router ospf 201 network 36.0.0.0 0.255.255.255 area 36.0.0.0 area 36.0.0.0 stub area 36.0.0.0 default-cost 20
area authentication
area stub
area-id | Identifier of the area about which routes are to be summarized. It can be specified as either a decimal value or as an IP address. |
address | IP address. |
mask | IP mask. |
Disabled
Router configuration
Multiple area router configuration commands specifying the range option can be configured. Thus, OSPF can summarize addresses for many different sets of address ranges.
The following example specifies one summary route to be advertised by the area border router to other areas for all subnets on network 36.0.0.0 and for all hosts on network 192.42.110.0:
interface ethernet 0 ip address 192.42.110.201 255.255.255.0 ! interface ethernet 1 ip address 36.56.0.201 255.255.0.0 ! router ospf 201 network 36.0.0.0 0.255.255.255 area 36.0.0.0 network 192.42.110.0 0.0.0.255 area 0 area 36.0.0.0 range 36.0.0.0 255.0.0.0 area 0 range 192.42.110.0 255.255.255.0
area-id | Identifier for the stub area. The identifier can be either a decimal value or an IP address. |
No stub area is defined.
Router configuration
This command must be configured on all routers in the stub area. Use the area router configuration command with the default-cost option to specify the cost of a default internal router sent into a stub area by an area border router.
There are two stub area router configuration commands: the stub and default-cost options of the area router configuration command. In all routers attached to the stub area, the area should be configured as a stub area using the stub option of the area command. Use the default-cost option only on an area border router attached to the stub area. The default-cost option provides the metric for the summary default route generated by the area border router into the stub area.
The following example assigns a default cost of 20 to stub network 36.0.0.0:
interface ethernet 0 ip address 36.56.0.201 255.255.0.0 ! router ospf 201 network 36.0.0.0 0.255.255.255 area 36.0.0.0 area 36.0.0.0 stub area 36.0.0.0 default-cost 20
area authentication
area default-cost
Use the area virtual-link router configuration command with the optional parameters to define an OSPF virtual link. Use the no form of this command to remove the virtual link.
area area-id virtual-link router-id [hello-interval seconds][retransmit-interval seconds]
area-id | Area ID assigned to the transit area for the virtual link. This can be either a decimal value or a valid IP address. There is no default. |
router-id | Router ID associated with the virtual link neighbor. The router ID appears in the show ip ospf display. It is internally derived by each router from the router's interface IP addresses. This value must be entered in the format of an IP address. There is no default. |
hello-interval | (Optional) Number of seconds between the Hello packets that the router sends on an interface. |
seconds | (Optional) Unsigned integer value to be advertised in the router's Hello packets. The value must be the same for all routers attached to a common network. The default is 10 seconds. |
retransmit-interval | (Optional) Number of seconds between link state advertisement retransmissions for adjacencies belonging to the interface. |
seconds | (Optional) Expected round-trip delay between any two routers on the attached network. The value must be greater than the expected round-trip delay. The default is 5 seconds. |
transmit-delay | (Optional) Estimated number of seconds it takes to transmit a link state update packet on the interface. |
seconds | (Optional) Integer value that must be greater than zero. Link state advertisements in the update packet have their age incremented by this amount before transmission. The default value is 1 second. |
dead-interval | (Optional) Number of seconds that a router's Hello packets are not seen before its neighbors declare the router down. |
seconds
| (Optional) Unsigned integer value. The default is four times the Hello interval. As with the Hello interval, this value must be the same for all routers attached to a common network. |
authentication-key | (Optional) Specific password to be used by neighboring routers. |
password | (Optional) Any continuous string of characters that you can enter from the keyboard up to 8 bytes in length. This string acts as a key that will allow the authentication procedure to generate or verify the authentication field in the OSPF header. This key is inserted directly into the OSPF header when originating routing protocol packets. A separate password can be assigned to each network on a per-interface basis. All neighboring routers on the same network must have the same password to be able to route OSPF traffic. There is no default value. The 8 bytes of password are encrypted in the configuration file if the service password-encryption command is enabled. |
See "Syntax Description" for various defaults.
Router configuration
In OSPF, all areas must be connected to a backbone area. If the connection to the backbone is lost, it can be repaired by establishing a virtual link.
The smaller the Hello interval, the faster topological changes will be detected, but more routing traffic will ensue.
The setting of the retransmit interval should be conservative, or needless retransmissions will result. The value should be larger for serial lines and virtual links.
The transmit delay value should take into account the transmission and propagation delays for the interface.
A router will use the specified authentication key only when authentication is enabled for the backbone with the area area-id authentication router configuration command.
Any argument specified after authentication-key password is ignored. Therefore, specify any optional arguments before authentication-key.
The following example establishes a virtual link with default values for all optional parameters:
router ospf 201 network 36.0.0.0 0.255.255.255 area 36.0.0.0 area 36.0.0.0 virtual-link 36.3.4.5
area authentication
Use the area-password router configuration command to configure the IS-IS area authentication password. The no area-password command disables the password.
area-password password
password | Password you assign. |
No area password is defined.
Router configuration
This password is inserted in Level 1 (station router level) link state PDUs (LSPs), complete sequence number PDUs (CSNPs), and partial sequence number PDUs (PSNP).
The following example assigns an area authentication password:
router isisarea-password angel
domain-password
This command has no arguments or keywords.
Enabled
Router configuration
By default, BGP does not accept subnets redistributed from IGP. To advertise and carry subnet routes in BGP, use an explicit network command or the no auto-summary command. If you disable auto-summarization and have not entered a network command, you will not advertise network routes for networks with subnet routes unless they contain a summary route.
In the following example, network numbers are not summarized automatically:
router bgp 6 no auto-summary
Use the autonomous-system global configuration command to specify the local autonomous system that the router resides in for EGP. To remove the autonomous system number, use the no autonomous-system command.
autonomous-system local-as
local-as | Local autonomous system number to which the router belongs |
No local autonomous system is specified.
Global configuration
Before you can set up EGP routing, you must specify an autonomous system number. The local autonomous system number will be included in EGP messages sent by the router.
The following sample configuration specifies an autonomous system number of 110:
autonomous-system 110
router egp
Use the bgp default local-preference command to change the default local preference value of 100. The no form of the command reverts to the default setting.
bgp default local-preference value
value | Local preference value. Higher is more preferred. Integer from 0 through 4294967295. |
Local preference value of 100
Router configuration
Generally, the default value of 100 allows you to easily define a particular path as less preferable than paths with no local preference attribute. The preference is sent to all routers in the local autonomous system.
In the following example, the default local preference value is raised from the default of 100 to 200:
router bgp 200 bgp default local-preference 200
set local-preference
Use the bgp fast-external-fallover router configuration command to immediately reset the BGP sessions of any directly adjacent external peers if the link used to reach them goes down. Use the no form of this command to disable this feature.
bgp fast-external-falloverThis command has no arguments or keywords.
Enabled
Router configuration
In the following example, the automatic resetting of BGP sessions is disabled:
router bgp 109 no bgp fast-external-fallover
Use the clear arp-cache EXEC command to remove all dynamic entries from the ARP cache and to clear the fast-switching cache.
clear arp-cacheThis command has no arguments or keywords.
EXEC
The following example removes all dynamic entries from the ARP cache and clears the fast-switching cache:
clear arp-cache
To reset a BGP connection, use the clear ip bgp EXEC command at the system prompt.
clear ip bgp {* | address}
* | Resets all current BGP sessions. |
address | Resets only the identified BGP neighbor. |
EXEC
Use this command whenever any of the following changes occur:
The following example shows how to reset all current BGP sessions:
clear ip bgp *
show ip bgp
timers bgp
Use the clear ip route EXEC command to remove one or more routes from the IP routing table.
clear ip route {network [mask] | *}
network | Network or subnet address to remove. |
mask | (Optional) Network mask associated with the IP address you wish to remove. |
* | Removes all entries. |
EXEC
The following example removes a route to network 132.5.0.0 from the IP routing table:
clear ip route 132.5.0.0
show ip route
Use the default-information allowed router configuration command to control exterior information between IGRP processes. The no default-information allowed in command causes IGRP exterior or default routes to be suppressed when received by an IGRP process. The no default-information allowed out command causes IGRP exterior routes to be suppressed in updates.
default-information allowed {in | out}
in | Allows IGRP exterior or default routes to be received by an IGRP process. |
out | Allows IGRP exterior routes to be advertised in updates. |
Normally, exterior routes are always accepted and default information is passed between IGRP processes when doing redistribution.
Router configuration
The default network of 0.0.0.0 used by RIP cannot be redistributed by IGRP.
The following example allows IGRP exterior or default routes to be received by the IGRP process in autonomous system 23:
router igrp 23 default-information allowed in
Use the default-information originate router configuration command to allow the redistribution of network 0.0.0.0 into BGP.
default-information originateThis command has no arguments or keywords.
Disabled
Router configuration
The same functionality will result from the network 0.0.0.0 command, using the network router configuration command.
The following example configures BGP to redistribute network 0.0.0.0 into BGP:
router bgp 164 default-information originate
Use the default-information originate router configuration command to explicitly configure EGP to generate a default route. The no default-information originate command disables this function.
default-information originateThis command has no arguments or keywords.
Disabled
Router configuration
Because EGP can use network 0.0.0.0 as a default route, EGP must be explicitly configured to generate a default route. If the next hop for the default route can be advertised as a third party, it will be included as a third party.
The following example configures EGP to generate a default route:
autonomous system 109 router egp 164 network 131.108.0.0 network 192.31.7.0 neighbor 10.2.0.2 default-information originate
Use the default-information originate router configuration command to generate a default route into an OSPF or IS-IS routing domain. The no default-information originate command disables generation of a default route into the specified OSPF or IS-IS routing domain.
default-information originate [always] [metric metric-value] [metric-type type-value]
originate | For OSPF, causes the router to generate a default external route into an OSPF domain if the router already has a default route and you want to propagate to other routers. For IS-IS, originates the default route whether or not it resides in the routing table. |
always | (Optional) For OSPF, the default route always will be advertised whether or not the router has a default route. |
metric metric-value | (Optional) Metric used for generating the default route. If a value is not specified for this option, and no value is specified using the default-metric router configuration command, the default metric value is 10. The value used is specific to the protocol. |
metric-type type-value | (Optional) For OSPF, the external link type associated with the default route advertised into the OSPF routing domain. It can be one of two values: 1---Type 1 external route 2---Type 2 external route If a metric-type is not specified, the router adopts a Type 2 external route. For IS-IS, it can be one of two values: internal---IS-IS metric which is < 63. external---IS-IS metric which is > 64 < 128. The default is internal. |
level-1 | For IS-IS only, Level 1 routes are redistributed into other IP routing protocols independently. It specifies if IS-IS advertises network 0.0.0.0 into the Level 1 area. |
level-1-2 | For IS-IS only, both Level 1 and Level 2 routes are redistributed into other IP routing protocols. It specifies if IS-IS advertises network 0.0.0.0 into both levels in a single command. |
level-2 | For IS-IS only, Level 2 routes are redistributed into other IP routing protocols independently. It specifies if IS-IS advertises network 0.0.0.0 into the Level 2 subdomain. |
route-map map-name | (Optional) Routing process will generate the default route if the route-map is satisfied. |
Disabled
Router configuration
Whenever you use the redistribute or the default-information router configuration commands to redistribute routes into an OSPF routing domain, the router automatically becomes an autonomous system boundary router. However, an autonomous system boundary router does not, by default, generate a default route into the OSPF routing domain. The router still needs to have a default route for itself before it generates one, except when you have specified the always keyword.
When you use this command for the OSPF process, the default network must reside in the routing table and you must satisfy the route-map map-name keyword. Use the default-information originate always route-map map-name form of the command when you do not want the dependency on the default network in the routing table.
If a router configured with this command has a route to 0.0.0.0 in the routing table, IS-IS will originate an advertisement for 0.0.0.0 in its LSPs.
In the following configuration, the router is forced to generate a default external route into an
IS-IS domain:
router isis ! BGP routes will be distributed into IS-IS redistribute bgp 120 ! access list 2 is applied to outgoing routing updates distribute-list 2 out ! metric of 60 is specified for default router redistributed into IS-IS
! routing domain. default-information originate metric 60 ! access list 2 defined as giving access to network 100.105.0.0 access-list 2 permit 100.105.0.0 0.0.255.255
The following example specifies a metric of 100 for the default route redistributed into the OSPF routing domain and an external metric type of Type 1:
router ospf 109 redistribute igrp 108 metric 100 subnets default-information originate metric 100 metric-type 1
isis metric
redistribute
Use the default-metric router configuration command to set default metric values for the RIP, EGP, IGRP, enhanced IGRP, and BGP routing protocols. Use the no default-metric command to remove the metric value and return to the default state.
default-metric number
number | Default metric value appropriate for the specified routing protocol |
Built-in, automatic metric translations, as appropriate for each routing protocol
Router configuration
This command is used in conjunction with the redistribute router configuration command to cause the current routing protocol to use the same metric value for all redistributed routes. A default metric helps solve the problem of redistributing routes with incompatible metrics. Whenever metrics do not convert, using a default metric provides a reasonable substitute and enables the redistribution to proceed.
In BGP, this sets the MULTI_EXIT_DISC metric. (The name of this metric for BGP Versions 2 and 3 is INTER_AS.)
The following example shows a router in autonomous system 109 using both the RIP and the IGRP routing protocols. The example advertises IGRP-derived routes using the RIP protocol and assigns the IGRP-derived routes a RIP metric of 10.
router rip default-metric 10 redistribute igrp 109
redistribute
Use this form of the default-metric router configuration command to set metrics for IGRP. Use the no default-metric command to remove the metric value and return to the default state.
default-metric bandwidth delay reliability loading mtu
bandwidth | Minimum bandwidth of the route in kilobits per second |
delay | Route delay in tens of microseconds |
reliability | Likelihood of successful packet transmission expressed as a number between 0 and 255 (255 is 100 percent reliability) |
loading | Effective bandwidth of the route expressed as a number between 0 and 255 (255 is 100 percent loading) |
mtu | Minimum Maximum Transmission Unit (MTU) size for the route |
Built-in, automatic metric translations
Router configuration
IGRP metric defaults have been carefully set to work for a wide variety of networks. Take great care in changing these values.
Automatic metric translations for IGRP are only supported when redistributing from IGRP or static.
The following example takes redistributed RIP metrics and translates them into IGRP metrics with values as follows: bandwidth = 1000, delay = 100, reliability = 250, loading = 100, and mtu =1500.
router igrp 109 network 131.108.0.0 redistribute rip default-metric 1000 100 250 100 1500
redistribute
Use the distance router configuration command to define an administrative distance. Use the no distance command with the appropriate arguments to remove a distance definition.
distance weight [address mask [access-list-number]] [ip]
weight | Integer from 10 to 255 for the administrative distance. (Values 0 through 9 are reserved for internal use.) Used alone, the argument specifies a default administrative distance that the router uses when no other specification exists for a routing information source. A distance of 255 is the maximum possible distance, and any route with that distance will not be installed in the routing table. |
address | (Optional) IP address. |
mask | (Optional) In dotted-decimal format which bits, if any, to ignore in the address value; a set bit in the mask argument instructs the router to ignore the corresponding bit in the address value. |
access-list-number | (Optional) Number of a standard IP access list to be applied to incoming routing updates. |
ip | (Optional) IP-derived routes for IS-IS. Can be applied independently for IP routes and ISO CLNS routes. |
See values in Table 17-1.
Router configuration
Numerically, an administrative distance is an integer between 0 and 255. In general, the higher the value, the lower the trust rating. An administrative distance of 255 means the routing information source cannot be trusted at all and should be ignored.
When the optional access list number is used with this command, it is applied when a network is being inserted into the routing table. This allows filtering of networks according to the IP address of the router supplying the routing information. This could be used, as an example, to filter out possibly incorrect routing information from routers not under your administrative control.
The order in which you enter distance commands can affect the assigned administrative distances in unexpected ways (see "Example" for further clarification).
Weight values are also subjective; there is no quantitative method for choosing weight values.
For BGP, the distance command sets the administrative distance of the External BGP route.
Default administrative distances are shown in Table 17-1.
| Route Source | Default Distance |
|---|---|
Connected interface | 0 |
Static route | 1 |
External BGP | 20 |
IGRP | 100 |
OSPF | 110 |
IS-IS | 115 |
RIP | 120 |
EGP | 140 |
Internal BGP | 200 |
Unknown | 255 |
The show ip protocols EXEC command displays the default administrative distance for a specified routing process.
In the following example, the router igrp global configuration command sets up IGRP routing in autonomous system number 109. The network router configuration commands specify IGRP routing on networks 192.31.7.0 and 128.88.0.0. The first distance router configuration command sets the default administrative distance to 255, which instructs the router to ignore all routing updates from routers for which an explicit distance has not been set. The second distance command sets the administrative distance for all routers on the Class C network 192.31.7.0 to 90. The third distance command sets the administrative distance for the router with the address 128.88.1.3 to 120.
router igrp 109 network 192.31.7.0 network 128.88.0.0 distance 255 distance 90 192.31.7.0 0.0.0.255 distance 120 128.88.1.3 0.0.0.0
distance bgp
Use the distance bgp router configuration command to allow the use of three possible administrative distances---external, internal, and local---that could be a better route to a node. Use the no distance bgp command to reset these values to their defaults.
distance bgp external-distance internal-distance local-distance
external-distance | Administrative distance for BGP external routes. External routes are routes for which the best path is learned from a neighbor external to the autonomous system. Acceptable values are from 1 to 255. A distance of 255 is the maximum possible distance, and any route with that distance will not be installed in the routing table. |
internal-distance | Administrative distance for BGP internal routes. Internal routes are those routes that are learned from another BGP entity within the same autonomous system. Acceptable values are from 1 to 255. A distance of 255 is the maximum possible distance, and any route with that distance will not be installed in the routing table. |
local-distance | Administrative distance for BGP local routes. Local routes are those networks listed with a network router configuration command, often as back doors, for that router or for networks that are being redistributed from another process. Acceptable values are from 1 to 255. A distance of 255 is the maximum possible distance, and any route with that distance will not be installed in the routing table. |
external-distance = 20
internal-distance = 200
local-distance = 200
Router configuration
An administrative distance is a rating of the trustworthiness of a routing information source, such as an individual router or a group of routers. Numerically, an administrative distance is an integer between 0 and 255. In general, the higher the value, the lower the trust rating. An administrative distance of 255 means the routing information source cannot be trusted at all and should be ignored.
Use this command if another protocol is known to be able to provide a better route to a node than was actually learned via external BGP, or if some internal routes should really be preferred by BGP.
In the following example, internal routes are known to be preferable to those learned through the IGP, so the administrative distance values are set accordingly:
router bgp 109 network 131.108.0.0 neighbor 129.140.6.6 remote-as 123 neighbor 128.125.1.1 remote-as 47 distance bgp 20 20 200
distance
Use the distribute-list in router configuration command to filter networks received in updates. (Not supported in IS-IS.) Use the no form of this command to disable this function.
distribute-list access-list-number in [interface-name]
access-list-number | Standard IP access list number. The list explicitly specifies which networks are to be received and which are to be suppressed. |
interface-name | (Optional) Interface on which the access list should be applied to incoming updates. If no interface is specified, the access list will be applied to all incoming updates. |
Disabled
Router configuration
The following example causes only two networks to be accepted by a RIP routing process: network 0.0.0.0 (the RIP default) and network 131.108.0.0.
access-list 1 permit 0.0.0.0 access-list 1 permit 131.108.0.0 access-list 1 deny 0.0.0.0 255.255.255.255 router rip network 131.108.0.0 distribute-list 1 in
A dagger () indicates that the command is documented in another chapter.
access-list
distribute-list out
redistribute
Use the distribute-list out router configuration command to suppress networks from being advertised in updates. Use the no form of this command to disable this function.
distribute-list access-list-number out {interface-name | routing-process}
access-list-number | Standard IP access list number. The list explicitly specifies which networks are to be sent and which are to be suppressed in routing updates. |
interface-name | Name of a particular interface. Does not apply to OSPF. |
routing-process | Name of a particular routing process, or static or connected. |
Disabled
Router configuration
When redistributing networks, a routing process name can be specified as an optional trailing argument to the distribute-list command. This causes the access list to be applied to only those routes derived from the specified routing process. After the process-specific access list is applied, any access list specified by a distribute-list command without a process name argument will be applied. Addresses not specified in the distribute-list command will not be advertised in outgoing routing updates.
The following example would cause only one network to be advertised by a RIP routing process: network 131.108.0.0.
access-list 1 permit 131.108.0.0 access-list 1 deny 0.0.0.0 255.255.255.255 router rip network 131.108.0.0 distribute-list 1 out
In the following example, access list 1 is applied to outgoing routing updates and IS-IS is enabled on interface Ethernet 0. Only network 131.131.101.0 will be advertised in outgoing IS-IS routing updates.
router isis redistribute ospf 109 distribute-list 1 out interface Ethernet 0 ip router isis access-list 1 permit 131.131.101.0 0.0.0.255
A dagger () indicates that the command is documented in another chapter.
access-list
distribute-list in
redistribute
Use the domain-password router configuration command to configure the IS-IS routing domain authentication password. The no domain-password command disables the password.
domain-password password
password | Password you assign |
No password is specified.
Router configuration
This password is inserted in Level 2 (area router level) link state PDUs (LSPs), complete sequence number PDUs (CSNPs), and partial sequence number PDUs (PSNP).
The following example assigns an authentication password to the routing domain:
router isis domain-password flower
area-password
Use the ip address interface configuration command to specify the IP address on an interface. The no ip address command removes the specified secondary address.
ip address address mask [secondary]
address | IP address |
mask | IP address mask |
secondary | (Optional) Address to be added as a secondary address |
Disabled
Interface configuration
The optional keyword secondary allows an unlimited number of secondary addresses to be specified. Secondary addresses are treated like primary addresses, except that the system never generates datagrams other than routing updates with secondary source addresses. IP broadcasts and ARP requests are handled properly, as are interface routes in the IP routing table.
Secondary IP addresses can be used in a variety of situations. The following are the most common applications:
The following example specifies 131.108.1.27 as the primary address and 192.31.7.17 as a secondary address for interface Ethernet 0:
interface ethernet 0 ip address 131.108.1.27 255.255.255.0 ip address 192.31.7.17 255.255.255.0 secondary
Use the ip as-path access-list global configuration command to define a BGP-related access list. To disable use of the access list, use the no ip as-path access-list command.
ip as-path access-list access-list-number {permit | deny} as-regular-expression
access-list-number | Integer from 1 to 199 that indicates the regular expression access list number. |
permit | Permits access for matching conditions. |
deny | Denies access to matching conditions. |
as-regular-expression | Autonomous system in the access list using a regular expression. See the "Regular Expressions" appendix for information on forming regular expressions. |
No access lists are defined.
Global configuration
You can specify an access list filter on both inbound and outbound BGP routes. In addition, you can assign weights based on a set of filters. Each filter is an access list based on regular expressions. If the regular expression matches the representation of the autonomous system path of the route as an ASCII string, then the permit or deny condition applies. The autonomous system path does not contain the local autonomous system number. Use the ip as-path access-list global configuration command to define an BGP access list, and the neighbor router configuration command to apply a specific access list.
See the "Regular Expressions" appendix for information on forming regular expressions.
The following example specifies that the BGP neighbor with IP address 128.125.1.1 is not sent advertisements about any path through or from the adjacent autonomous system 123.
ip as-path access-list 1 deny _123_ ip as-path access-list 1 deny ^123 .* ! The space in the above expression (^123.*) is required. router bgp 109 network 131.108.0.0 neighbor 129.140.6.6 remote-as 123 neighbor 128.125.1.1 remote-as 47 neighbor 128.125.1.1 filter-list 1 out
neighbor distribute-list
neighbor filter-list
Use the ip default-network global configuration command to select a network as a candidate route for computing the gateway of last resort. Use the no default-network command to remove the route.
ip default-network network-number
network-number | Number of the network |
If the router has a directly connected interface onto the specified network, the dynamic routing protocols running on that router will generate (or source) a default route. For RIP, this is flagged as the pseudonetwork 0.0.0.0; for IGRP, it is the network itself, flagged as an exterior route.
Global configuration
The router uses both administrative distance and metric information to determine the default route. Multiple ip default-network commands can be given. All candidate default routes, both static (that is, flagged by ip default-network) and dynamic, appear in the routing table preceded by an asterisk.
If the IP routing table indicates that the specified network number is subnetted and a non-zero subnet number is specified, then the system will automatically configure a static summary route. This static summary route is configured instead of a default network. The effect of the static summary route is to cause traffic destined for subnets that are not explicitly listed in the IP routing table to be routed using the specifed subnet.
The following example defines a static route to network 10.0.0.0 as the static default route:
ip route 10.0.0.0 255.0.0.0 131.108.3.4 ip default-network 10.0.0.0
ip default-network 129.140.0.0
show ip route
Use the ip gdp interface configuration command to enable GDP routing on an interface. The no ip gdp command disables GDP routing, with all default parameters.
ip gdp [priority number | reporttime seconds | holdtime seconds]
priority number | (Optional) Alters the GDP priority; default is a priority of 100. A larger number indicates a higher priority. |
reporttime seconds | (Optional) Alters the GDP reporting interval; the default is 5 seconds for broadcast media such as Ethernets, and never for nonbroadcast media such as X.25. |
holdtime seconds | (Optional) Alters the GDP default hold time of 15 seconds. |
priority = 100
reporttime = 5 seconds for broadcast media; 0 for nonbroadcast media
holdtime = 15 seconds
Interface configuration
When enabled on an interface, GDP updates report the primary and secondary IP addresses of that interface.
In the following example, GDP is enabled on interface Ethernet 1 with a report time of 10 seconds, and priority and hold time set to their defaults (because none are specified):
ip gdp reporttime 10
Use the ip irdp interface configuration command to enable ICMP Router Discovery Protocol (IRDP) processing on an interface. The no ip irdp command disables IRDP routing on the specified interface.
ip irdp [multicast | holdtime seconds | maxadvertinterval seconds | minadvertinterval
multicast | (Optional) Use the multicast address (224.0.0.1) instead of IP broadcasts. |
holdtime seconds | (Optional) Length of time in seconds advertisements are held valid. Default is three times the maxadvertinterval value. Must be greater than maxadvertinterval and cannot be greater than 9000 seconds. |
maxadvertinterval seconds | (Optional) Maximum interval in seconds between advertisements. The default is 600 seconds. |
minadvertinterval seconds | (Optional) Minimum interval in seconds between advertisements. The default is 0.75 times the maxadvertinterval. If you change the maxadvertinterval value, this value defaults to three-quarters of the new value. |
preference number | (Optional) Router's preference value. The allowed range is -231 to 231. The default is 0. A higher value increases the router's preference level. You can modify a particular router so that it will be the preferred router to which others home. |
address address [number] | (Optional) IP address (address) to proxy-advertise, and optionally, its preference value (number). |
Disabled.
When enabled, IRDP uses these defaults:
Interface configuration
If you change maxadvertinterval, the other two values also change, so it is important to change maxadvertinterval first before changing either holdtime or minadvertinterval.
The following example illustrates how to set the various IRDP processes:
! enable irdp on interface Ethernet 0 interface ethernet 0
ip irdp
! send IRDP advertisements to the multicast address ip irdp multicast
! increase router preference from 100 to 50 ip irdp preference 50
! set maximum time between advertisements to 400 secs ip irdp maxadvertinterval 400
! set minimum time between advertisements to 100 secs ip irdp minadvertinterval 100
! advertisements are good for 6000 seconds ip irdp holdtime 6000
! proxy-advertise 131.108.14.5 with default router preference ip irdp address 131.108.14.5
! proxy-advertise 131.108.14.6 with preference of 50 ip irdp address 131.108.14.6 50
Use the ip ospf authentication-key interface configuration command to assign a password to be used by neighboring routers that are using OSPF's simple password authentication. The no ip ospf authentication-key command removes any previously assigned OSPF password.
ip ospf authentication-key password
password | Any continuous string of characters that can be entered from the keyboard up to 8 bytes in length. |
No password is specified.
Interface configuration
The password created by this command is used as a "key" that is inserted directly into the OSPF header when the router originates routing protocol packets. A separate password can be assigned to each network on a per-interface basis. All neighboring routers on the same network must have the same password to be able to exchange OSPF information.
In the following example, the authentication key is enabled with the string yourpass:
ip ospf authentication-key yourpass
area authentication
Use the ip ospf cost interface configuration command to explicitly specify the cost of sending a packet on an interface. The no ip ospf cost command resets the path cost for an interface to the default value.
ip ospf cost cost
cost | Unsigned integer value expressed as the link state metric. The range is from 1 to 65535. |
See "Usage Guidelines"
Interface configuration
Unlike IGRP, you must set this metric manually using this command, if you need to change the default. Changing the bandwidth does not change the link cost.
The link state metric is advertised as the link cost in the router's router link advertisement. We do not support Type of Service (TOS), so you can assign only one cost per interface.
In general, the path cost is calculated as follows:
108 ÷ Bandwidth
Using the above formula, the default path costs were calculated as noted in the following list. If these values do not suit your network, you can use your own method of calculating path costs.
The following example sets the interface cost value to 65:
ip ospf cost 65
Use the ip ospf dead-interval interface configuration command to set the number of seconds that a router's Hello packets must not have been seen before its neighbors declare the router down. The no ip ospf dead-interval command resets the length of time to the default value.
ip ospf dead-interval seconds
seconds | Unsigned integer that specifies the interval in seconds; the value must be the same for all nodes on the network. |
Four times the interval set for the ip ospf hello-interval command
Interface configuration
The interval is advertised in the router's Hello packets. This value must be the same for all routers on a specific network.
The following example sets the OSPF dead interval to 60 seconds:
interface ethernet 1
ip ospf dead-interval 60
ip ospf hello-interval
Use the ip ospf hello-interval interface configuration command to specify the interval between Hello packets that the router sends on the interface. The no ip ospf hello-interval command resets the interval to the default value.
ip ospf hello-interval seconds
seconds | Unsigned integer that specifies the interval in seconds. The value must be the same for all nodes on a specific network. |
10 seconds
Interface configuration
This value is advertised in the router's Hello packets. The smaller the Hello interval, the faster topological changes will be detected, but more routing traffic will ensue. This value must be the same for all routers on a specific network.
The following example sets the interval between Hello packets to 15 seconds:
interface ethernet 1 ip ospf hello-interval 15
ip ospf dead-interval
Use the ip ospf-name-lookup global configuration command to configure OSPF to look up Domain Name System (DNS) names for use in all OSPF show EXEC command displays. The
no ip ospf-name-lookup command disables the feature.
This command has no arguments or keywords.
Disabled
Global configuration
This feature makes it easier to identify a router because it is displayed by name rather than by its router ID or neighbor ID.
The following example configures OSPF to look up DNS names for use in all OSPF show EXEC command displays:
ip ospf-name-lookup
The following is sample output of the show ip ospf database EXEC command, for example, once you have enabled the DNS name lookup feature.
Router# show ip ospf database
OSPF Router with id (160.89.41.1) (Autonomous system 109)
Router Link States (Area 0.0.0.0)
Link ID ADV Router Age Seq# Checksum Link count
160.89.41.1 router 381 0x80000003 0x93BB 4
160.89.34.2 neon 380 0x80000003 0xD5C8 2
Net Link States (Area 0.0.0.0)
Link ID ADV Router Age Seq# Checksum
160.89.32.1 router 381 0x80000001 0xC117
Use the ip ospf network interface configuration command to configure the OSPF network type to a type other than the default for a given media. The no ip ospf network command restores the default.
ip ospf network {broadcast | non-broadcast}
broadcast | Sets the network type to broadcast. |
non-broadcast | Sets the network type to nonbroadcast. |
Depends on the network type
Interface configuration
Using this feature, you can configure broadcast networks as nonbroadcast multiaccess networks when, for example, you have routers in your network that do not support multicast addressing. You can also configure nonbroadcast multiaccess networks, such as X.25, Frame Relay, and SMDS, as broadcast networks. This feature saves you from having to configure neighbors.
If this command is issued on an interface that does not allow it, it will be ignored.
The following example sets your OSPF network as a broadcast network:
interface serial 0
ip address 160.89.77.17 255.255.255.0 ip ospf network broadcast encapsulation frame-relay
neighbor (OSPF)
x25-map
frame-relay map
Use the ip ospf priority interface configuration command to set the router's priority, which helps determine the designated router for this network. The no ip ospf priority command resets the router priority to the default value.
ip ospf priority number
number | 8-bit unsigned integer that specifies the priority. The range is from 0 to 255. |
Priority of 1
Interface configuration
When two routers attached to a network both attempt to become the designated router; the one with the higher router priority takes precedence. If there is a tie, the router with the higher router ID takes precedence. A router with a router priority set to zero is ineligible to become the designated router or backup designated router. Router priority is only configured for interfaces to multiaccess networks (in other words, not point-to-point networks).
This priority value is used when you configure OSPF for nonbroadcast networks using the neighbor router configuration command for OSPF.
The following example sets the router priority value to 4:
interface ethernet 0
ip ospf priority 4
ip ospf network
neighbor (OSPF)
To specify the number of seconds between link state advertisement retransmissions for adjacencies belonging to the interface, use the ip ospf retransmit-interval interface configuration command. The no ip ospf retransmit-interval command resets the link state advertisement retransmission interval to the default value.
ip ospf retransmit-interval seconds
seconds | Number of seconds between retransmissions; it must be greater than the expected round-trip delay between any two routers on the attached network. The range is 1 to 65535 seconds. The default is 5 seconds. |
5 seconds
Interface configuration
When a router sends a link state advertisement (LSA) to its neighbor, it keeps the LSA until it receives back the acknowledgment. If it receives no acknowledgment in seconds, it will retransmit the LSA.
The setting of this parameter should be conservative, or needless retransmission will result. The value should be larger for serial lines and virtual links.
The following example sets the retransmit-interval value to 8 seconds:
interface ethernet 2
ip ospf retransmit-interval 8
Use the ip ospf transmit-delay interface configuration command to set the estimated number of seconds it takes to transmit a link state update packet on the interface. The no ip ospf transmit-delay command resets the estimated transmission time to the default value.
ip ospf transmit-delay seconds
seconds | Integer that specifies the number of seconds it takes to transmit a link state update. The range is 1 to 65535 seconds. |
1 second
Interface configuration
Link state advertisements in the update packet must have their age incremented by the amount specified in the seconds argument before transmission. The value assigned should take into account the transmission and propagation delays for the interface.
If the delay is not added before transmission over a link, the time in which the LSA propagates over the link is not considered. This setting has more significance on very low speed links.
The following example sets the retransmit-delay value to 3 seconds:
interface ethernet 0
ip ospf transmit-delay 3
Use the ip route global configuration command to establish static routes. The no ip route command removes the static routes.
ip route network [mask] {address | interface} [distance]
network | Internet address of the target network or subnet |
mask | (Optional) Network mask that lets you mask network and subnetwork bits |
address | Internet address of the next hop that can be used to reach that network |
interface | Network interface to use |
distance | (Optional) An administrative distance |
No static routes are established.
Global configuration
A static route is appropriate when the router cannot dynamically build a route to the destination.
If you specify an administrative distance, you are flagging a static route that can be overridden by dynamic information. For example, IGRP-derived routes have a default administrative distance of 100. To have a static route that would be overridden by an IGRP dynamic route, specify an administrative distance greater than 100. Static routes have a default administrative distance of 1.
Static routes that point to an interface will be advertised via RIP, IGRP, and other dynamic routing protocols, regardless of whether redistribute static commands were specified for those routing protocols. This is because static routes that point to an interface are considered in the routing table to be connected and hence lose their static nature. However, if you define a static route to an interface that is not one of the networks defined in a network command, no dynamic routing protocols will advertise the route unless a redistribute static command is specified for these protocols.
In the following example, an administrative distance of 110 was chosen. In this case, packets for network 10.0.0.0 will be routed through to the router at 131.108.3.4 if dynamic information with administrative distance less than 110 is not available.
ip route 10.0.0.0 255.0.0.0 131.108.3.4 110
In the following example, packets for network 131.108.0.0 will be routed to the router at 131.108.6.6:
ip route 131.108.0.0 255.255.0.0 131.108.6.6
Use the ip router isis interface configuration command to configure an IS-IS routing process for IP over a specified interface. The no ip router isis command disables IS-IS for IP on the interface.
ip router isis [tag]
tag | (Optional) Defines a meaningful name for a routing process. If not specified, a null tag is assumed. It must be unique among all IP router processes for a given router. Use the same text for the argument tag as specified in the router isis global configuration command. |
No routing processes are specified.
Interface configuration
The following example specifies IS-IS as an IP routing protocol for a process named Finance, and specifies that the Finance process will be routed on interfaces Ethernet 0 and serial 0:
router isis Finance interface Ethernet 0 ip router isis Finance interface serial 0 ip router isis Finance
router isis
Use the ip split-horizon interface configuration command to enable the split-horizon mechanism. The no ip split-horizon command turns off the split-horizon mechanism.
ip split-horizonThis command has no arguments or keywords.
Varies with media
Interface configuration
For all interfaces except those for which either Frame Relay or SMDS encapsulation is enabled, the default condition for this command is ip split-horizon; in other words, the split horizon feature is active. If the interface configuration includes either the encapsulation frame-relay or encapsulation smds interface configuration commands, then the default is for split horizon to be disabled. Split horizon is not disabled by default for interfaces using any of the X.25 encapsulations.
If split horizon has been disabled on an interface and you wish to enable it, use the ip split-horizon command to restore the split horizon mechanism.
The following example illustrates a simple example of disabling split horizon on a serial link. In this example, the serial link is connected to an X.25 network:
interface serial 0 encapsulation x25 no ip split-horizon
Use the is-type router configuration command to configure the IS-IS level at which the router will operate. The no is-type command resets the parameter to the default.
is-type {level-1 | level-1-2 | level-2-only}
level-1 | Router acts as a station router. |
level-1-2 | Router acts as both a station router and an area router. |
level-2-only | Router acts as an area router only. |
Router acts as both a station router and an area router.
Router configuration
The following example specifies an area router:
router isis is-type level-2-only
Use the isis circuit-type interface configuration command to configure the type of adjacency desired for the specified interface. The no isis circuit-type command resets the circuit type to Level l and Level 2.
isis circuit-type {level-1 | level-1-2 | level-2-only}
level-1 | A Level 1 adjacency may be established if there is at least one area address in common between this system and its neighbors. |
level-1-2 | A Level 1 and Level 2 adjacency is established if the neighbor is also configured as level-1-2 and there is at least one area in common. If there is no area in common, a Level 2 adjacency is established. This is the default. |
level-2-only | A Level 2 adjacency is established if and only if the neighbor is configured exclusively to be a Level 2 router. |
A Level 1 and Level 2 adjacency is established.
Interface configuration
In the following example, a router is configured to require Level 1 adjacency if there is at least one area address in common between this system and its neighbors:
ip router isis interface serial 0 isis circuit-type level-1
Use the isis csnp-interval interface configuration command to configure the IS-IS complete sequence number PDUs (CSNP) interval for the specified interface. The no isis csnp-interval command restores the default value.
isis csnp-interval seconds {level-1 | level-2}
seconds | Interval of time between transmission of CSNPs on multiaccess networks. This interval only applies for the designated router. The default is 10 seconds. |
level-1 | Configures the interval of time between transmission of CSNPs for Level 1 independently. |
level-2 | Configures the interval of time between transmission of CSNPs for Level 2 independently. |
10 seconds
Interface configuration
This command only applies for the designated router (DR) for a specified interface. Only DRs send CSNP packets in order to maintain database synchronization. The CSNP interval can be configured independently for Level 1 and Level 2. This feature does not apply to serial point-to-point interfaces. It does apply to WAN connections if the WAN is viewed as a multiaccess meshed network.
In the following example, interface serial 0 is configured for transmitting CSN PDUs every 5 seconds. The router is configured to act as a station router.
interface serial 0 isis csnp-interval 5 level-1
Use the isis hello-interval interface configuration command to specify the length of time, in seconds, between Hello packets that the router sends on the specified interface. The no isis hello-interval command restores the default value.
isis hello-interval seconds {level-1 | level-2}
seconds | Unsigned integer value. A value three times the Hello interval seconds is advertised as the holdtime in the Hello packets transmitted. It must be the same for all routers attached to a common network. With smaller Hello intervals, topological changes are detected faster, but there is more routing traffic. The default is 10 seconds. |
level-1 | Configures the Hello interval for Level 1 independently. Use this on X.25, SMDS, and Frame Relay multiaccess networks. |
level-2 | Configures the Hello interval for Level 2 independently. Use this on X.25, SMDS, and Frame Relay multiaccess networks. |
10 seconds
Interface configuration
The Hello interval can be configured independently for Level 1 and Level 2, except on serial point-to-point interfaces. (Because there is only a single type of Hello packet sent on serial links, it is independent of Level 1 or Level 2.) The level-1 and level-2 keywords are used on X.25, SMDS, and Frame Relay multiaccess networks.
In the following example, interface serial 0 is configured to advertise Hello packets every 5 seconds. The router is configured to act as a station router. This will cause more traffic than configuring a longer interval, but topological changes will be detected faster.
interface serial 0 isis hello-interval 5 level-1
Use the isis metric interface configuration command to configure the metric (or cost) for the specified interface. The no isis metric command restores the default metric value.
isis metric default-metric [delay-metric [expense-metric [error-metric]]] {level-1 | level-2}
default-metric | Metric used for the redistributed route. The default metric is used as a value for the IS-IS metric. This is the value assigned when there is no QOS routing performed. Only this metric is supported by Cisco routers. You can configure this metric for Level 1 and/or Level 2 routing. The range is from 0 to 63. The default value is 10. |
delay-metric | Not supported. |
expense-metric | Not supported. |
error-metric | Not supported. |
level-1 | Router acts as a station router (Level 1) only. |
level-2 | Router acts as an area router (Level 2) only. |
default-metric = 10
Interface configuration
Specifying the level-1 or level-2 keywords resets the metric only for Level 1 or Level 2 routing, respectively.
In the following example, interface serial 0 is configured for a default link-state metric cost of 15 for Level 1:
interface serial 0 isis metric 15 level-1
default-information
redistribute
Use the isis password interface configuration command to configure the authentication password for a specified interface. The no isis password command disables authentication for IS-IS.
isis password password {level-1 | level-2}
password | Authentication password you assign for an interface. |
level-1 | Configures the authentication password for Level 1 independently. For Level 1 routing, the router acts as a station router only. |
level-2 | Configures the authentication password for Level 2 independently. For Level 2 routing, the router acts as an area router only. |
Disabled
Interface configuration
Different passwords can be assigned for different routing levels using the level-1 and level-2 keyword arguments.
Specifying the level-1 or level-2 keywords disables the password only for Level 1 or Level 2 routing, respectively. If no keyword is specified, the default is level-1.
The following example configures a password for interface serial 0 at Level 1:
interface serial 0 isis password frank level-1
Use the isis priority interface configuration command to configure the priority of designated routers. The no isis priority command resets priority to 64.
isis priority value {level-1 | level-2}
value | Sets the priority of a router and is a number from 0 to 127. The default value is 64. |
level-1 | Sets the priority of a router for Level 1 independently. |
level-2 | Sets the priority of a router for Level 2 independently. |
Priority of 64
Interface configuration
Priorities can be configured for Level 1 and Level 2 independently. Specifying the level-1 or
level-2 keywords resets priority only for Level 1 or Level 2 routing, respectively.
The following example shows Level 1 routing given priority by setting the priority level to 50:
interface serial 0 isis priority 50 level-1
Use the isis retransmit-interval interface configuration command to configure the number of seconds between retransmission of IS-IS link-state PDU (LSP) retransmission for point-to-point links. The no isis retransmit-interval command restores the default value.
isis retransmit-interval seconds
seconds | Integer that should be greater than the expected round-trip delay between any two routers on the attached network. The setting of this parameter should be conservative, or needless retransmission will result. The value should be larger for serial lines and virtual links. The default value is 5 seconds. |
5 seconds
Interface configuration
The following example configures interface serial 0 for retransmission of IS-IS LSP every
10 seconds for a large serial line:
interface serial 0 isis retransmit-interval 10
A dagger () indicates that the command is documented in another chapter.
encapsulation ppp
frame-relay keepalive
smds dxi
Use the match as-path route-map configuration command to match a BGP autonomous system path access list. Use the no form of this command to remove the path list entry.
match as-path path-list-number
path-list-number | Autonomous system path access list. An integer from 1 through 199. |
No path lists are defined.
Route-map configuration
The values set by the match and set commands override global values. For example, the weights assigned with the match as-path and set weight route-map commands override the weights assigned using the neighbor weight and neighbor filter-list commands.
A route map can have several parts. Any route that does not match at least one match clause relating to a route- map command will be ignored; that is, the route will not be advertised for outbound route maps and will not be accepted for inbound route maps. If you want o modify only some data, you must configure second route-map section with an explicit match specified.
The implemented weight is based on the first matched autonomous system path.
In the following example, the AS path is set to match BGP autonomous system path access list 20:
route-map igp2bgp match as-path 20
route-map
set
Use the match interface route-map configuration command to distribute any routes that have their next hop out one of the interfaces specified. Use the no form of this command to remove the match interface entry.
match interface name unit...name unit
name unit | Names of interfaces, such as Ethernet 0 or Serial 2. |
No match interfaces are defined.
Route-map configuration
The match route-map configuration command has multiple formats. The match commands may be given in any order, and all match commands must "pass" to cause the route to be redistributed according to the set actions given with the set commands. The no forms of the match commands remove the specified match criteria.
A route map can have several parts. Any route that does not match at least one match clause relating to a route- map command will be ignored; that is, the route will not be advertised for outbound route maps and will not be accepted for inbound route maps. If you want o modify only some data, you must configure second route-map section with an explicit match specified.
In the following example, routes that have their next hop out interface Ethernet 0 will be distributed:
route-map name match interface ethernet 0
route-map
set
Use the match ip address route-map configuration command to distribute any routes that have a destination network number address that is permitted by a standard access list. Use the no form of this command to remove the match ip address entry.
match ip address access-list-number...access-list-number
access-list-number | One or more numeric identifiers of access lists. An integer from 1 through 99. |
No access list numbers are specified.
Route-map configuration
The match route-map configuration command has multiple formats. The match commands may be given in any order, and all match commands must "pass" to cause the route to be redistributed according to the set actions given with the set commands. The no forms of the match commands remove the specified match criteria.
A route map can have several parts. Any route that does not match at least one match clause relating to a route- map command will be ignored; that is, the route will not be advertised for outbound route maps and will not be accepted for inbound route maps. If you want o modify only some data, you must configure second route-map section with an explicit match specified.
In the following example, routes that have addresses specified by access list numbers 5 and 80 will be distributed:
route-map name match ip address 5 80
route-map
set
Use the match ip next-hop route-map configuration command to redistribute any routes that have a next-hop router address passed by one of the access lists specified. Use the no form of this command to remove the next-hop entry.
match ip next-hop access-list-number...access-list-number
access-list-number | One or more numeric identifiers of standard access lists. An integer from 1 through 99. |
Routes are distributed freely, without being required to match a next-hop address.
Route-map configuration
The match route-map configuration command has multiple formats. The match commands may be given in any order, and all match commands must "pass" to cause the route to be redistributed according to the set actions given with the set commands. The no forms of the match commands remove the specified match criteria.
A route map can have several parts. Any route that does not match at least one match clause relating to a route- map command will be ignored; that is, the route will not be advertised for outbound route maps and will not be accepted for inbound route maps. If you want o modify only some data, you must configure second route-map section with an explicit match specified.
In the following example, routes that have a next-hop router address passed by access list 5 or 80 will be distributed:
route-map name match ip next-hop 5 80
route-map
set
Use the match ip route-source route-map configuration command for any routes that have been advertised by routers at the address specified by the access lists. Use the no form of this command to remove the route-source entry.
match ip route-source access-list-number...access-list-number
access-list-number | One or more numeric identifiers of access lists. An integer from 1 through 99. |
No filtering on route source.
Route-map configuration
The match route-map configuration command