Specifications

next-address
MP-374
Cisco IOS Multiprotocol Label Switching Command Reference
January 2010
• In Cisco IOS Releases 12.2(33)SRD and 12.4(24)T, and Cisco XE Release 2.4 and earlier releases,
you cannot specify an explicit path that uses a link address as the first hop and then node addresses
as the subsequent hops. However, you can use a node address as the first hop andlink addresses as
the subsequent hops.
• In Cisco IOS Releases after 12.2(33)SRD, 12.4(24)T , and Cisco XE Release 2.4, you can use a link
address as the first hop and then node addresses as the subsequent hops. There are no restrictions
when specifying a mixture of link and node addresses.
When specifying an explicit path, if you specify the “forward” address (the address of the interface that
fo
rwards the traffic to the next router) as the next-hop address, the explicit path might not be used. Using
the forward address allows that entry to be treated as a loose hop for path calculation. Cisco recommends
that you use the “receive”address (the address of the interface that receives traffic from the sending
router) as the next-hop address.
In the following example, router R3 sends traffic to router R1. The paths marked a,b and x,y between
r
outers R1 and R2 are parallel paths.
R1(a)----(b)R2(c)--(d)R3
(x)----(y)
If you configure an explicit path from R3 to R1 using the “forward” addresses (addresses d and b), the
tunnel might reroute traffic over the parallel path (x,y) instead of the explicit path. To ensure that the
tunnel uses the explicit path, specify the “receive” addresses as part of the next-address command, as
shown in the following example:
ip explicit-path name path1
next-address (c)
next-address (a)
Examples The following example shows how to assign the number 60 to the IP explicit path, enable the path, and
specify 10.3.27.3 as the next IP address in the list of IP addresses:
Router(config)# ip explicit-path identifier 60 enable
Router(cfg-ip-expl-path)# next-address 10.3.27.3
Explicit Path identifier 60:
1: next-address 10.3.27.3
The following example shows a loose IP explicit path with ID 60. An interarea TE tunnel has a
destination of 10.3.29.3 and traverses ASBRs 10.3.27.3 and 10.3.28.3.
Router(config)# ip explicit-path identifier 60
Router(cfg-ip-expl-path)# next-address loose 10.3.27.3
Router(cfg-ip-expl-path)# next-address loose 10.3.28.3
Router(cfg-ip-expl-path)# next-address loose 10.3.29.3
Related Commands Command Description
append-after Inserts the new path entry after the specified index number.
index Inserts or modifies a path entry at a specified index.
ip explicit-path Enters the subcommand mode for IP explicit paths and creates
o
r modifies the specified path.
list Displays all or part of the explicit paths.
show ip explicit-paths Displays configured IP explicit paths.