Cisco Cisco IOS Software Release 12.2(33)SRE

On a fast-reroutable TE LSP with no backup tunnel, create a hello instance with the neighbor 
downstream (next hop (NHOP)). 

On a non-fast-reroutable TE LSP, create a hello instance with the neighbor downstream (NHOP) and 
the neighbor upstream (previous hop (PHOP)). This is in addition to the existing hellos for Fast 
Reroute. 

If both Fast Reroute and hellos for state timeout hello instances are needed on the same link, only one 
hello instance is created. It will have the Fast Reroute configuration including interval, missed refreshes, 
and DSCP. When a neighbor is down, Fast Reroute and the hello state timer take action.

This section provides a configuration example for the MPLS TE—RSVP Hello State Timer feature:

In the following example, the hello state timer is enabled globally and on an interface; and related 
parameters, including a DSCP value, a refresh interval, and a missed refresh limit are set on an interface.

Router# configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)# ip rsvp signalling hello

Router(config)# interface Ethernet 0/0

Router(config-if)# ip rsvp signalling hello

Router(config-if)# ip rsvp signalling hello reroute dscp 30

Router(config-if)# ip rsvp signalling hello reroute refresh interval 5000

Router(config-if)# ip rsvp signalling hello reroute refresh misses 5

Router(config-if)# end

The following example verifies the status of the hello state timer (reroute):

Router# show ip rsvp hello

Hello:

  Fast-Reroute/Reroute:Enabled

    Statistics:Enabled

  Graceful Restart:Enabled (help-neighbor only)