This article provides information on how to identify the active routes that are using a particular RSVP LSP as the next hop.

How to identify the active routes that are using a particular RSVP LSP as the next hop.

The Rt counter in the output of show mpls lsp' or 'show rsvp session shows the number of active routes, which are associated with an RSVP LSP. To list the active routes, which are currently using this LSP, you can use the following sequence of commands.

LSP Ingress:

On the ingress PE for a particular LSP, use show route label-switched-path <lsp-name> table inet.0 and show route label-switched-path <lsp-name> table inet6.0. The Rt counter, which is displayed in the output of the above mentioned commands, will be the sum of these route counts.

lab@router> show mpls lsp ingress count-active-routes
Ingress LSP: 2 sessions
To From State Rt P ActivePath LSPname
1.1.1.3 1.1.1.1 Up 5 * p1-to-p2
1.1.1.5 1.1.1.1 Up 0 * p1-to-p3
Total 2 displayed, Up 2, Down 0

lab@router> show route label-switched-path p1-to-p2

inet.0: 20 destinations, 20 routes (20 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.100.200.1/32 *[BGP/170] 6d 03:48:54, localpref 100, from 1.1.1.3
AS path: I
> to 11.12.0.2 via ge-0/0/2.2, label-switched-path p1-to-p2
10.100.200.2/32 *[BGP/170] 6d 03:48:54, localpref 100, from 1.1.1.3
AS path: I
> to 11.12.0.2 via ge-0/0/2.2, label-switched-path p1-to-p2
10.100.200.3/32 *[BGP/170] 6d 03:48:54, localpref 100, from 1.1.1.3
AS path: I
> to 11.12.0.2 via ge-0/0/2.2, label-switched-path p1-to-p2
10.100.200.4/32 *[BGP/170] 6d 03:48:54, localpref 100, from 1.1.1.3
AS path: I
> to 11.12.0.2 via ge-0/0/2.2, label-switched-path p1-to-p2
10.100.200.5/32 *[BGP/170] 6d 03:48:54, localpref 100, from 1.1.1.3
AS path: I
> to 11.12.0.2 via ge-0/0/2.2, label-switched-path p1-to-p2

inet.3: 8 destinations, 14 routes (6 active, 0 holddown, 6 hidden)
+ = Active Route, - = Last Active, * = Both

1.1.1.3/32 *[RSVP/7/1] 6d 00:07:01, metric 20
> to 11.12.0.2 via ge-0/0/2.2, label-switched-path p1-to-p2
10.1.2.3/32 *[RSVP/7/1] 6d 00:07:01, metric 20
> to 11.12.0.2 via ge-0/0/2.2, label-switched-path p1-to-p2

iso.0: 1 destinations, 1 routes (1 active, 0 holddown, 0 hidden)

mpls.0: 9 destinations, 9 routes (9 active, 0 holddown, 0 hidden)

lab@router>

Note:

• The count-active-routes knob may be required to obtain the number of active routes that are associated with each LSP. For more information, refer to KB25119 - [M/MX/T-series] Command to check the number of routes that are associated with each RSVP LSP.


• As mentioned above, only active routes in 'inet.0' and 'inet6.0' or 'mpls.0' that are using the given RSVP LSP are counted against the 'Rt' counter.


• For example, in the output shown above, inet.3 routes are LDP routes that are using RSVP LSP as NH, due to the 'ldp-tunneling' configuration. These routes are not counted against the 'Rt' counter.

LSP Transit:

On a transit router, show route label-switched-path <lsp-name> table mpls.0 should be used to display the routes:

lab@router1> show mpls lsp count
Ingress LSP: 0 sessions
Total 0 displayed, Up 0, Down 0

Egress LSP: 0 sessions
Total 0 displayed, Up 0, Down 0

Transit LSP: 6 sessions
To From State Rt Style Labelin Labelout LSPname
1.1.1.1 1.1.1.3 Up 1 1 FF 300704 3 p2-to-p1
1.1.1.1 1.1.1.5 Up 1 1 FF 300768 3 p3-to-p1
1.1.1.3 1.1.1.1 Up 1 1 FF 300752 3 p1-to-p2
1.1.1.3 1.1.1.5 Up 1 1 FF 300720 3 p3-to-p2
1.1.1.5 1.1.1.1 Up 1 1 FF 300688 3 p1-to-p3
1.1.1.5 1.1.1.3 Up 1 1 FF 300736 3 p2-to-p3
Total 6 displayed, Up 6, Down 0

lab@router1> show route label-switched-path p1-to-p2

inet.0: 16 destinations, 16 routes (16 active, 0 holddown, 0 hidden)

iso.0: 1 destinations, 1 routes (1 active, 0 holddown, 0 hidden)

mpls.0: 15 destinations, 15 routes (15 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

300752 *[RSVP/7/1] 6d 00:07:57, metric 1
> to 12.13.0.2 via ge-0/0/2.3, label-switched-path p1-to-p2

lab@router1>