Discussion

the set rsvp interface command to configure these interfaces in the [edit protocols]
hierarchy. As with MPLS, do not include the lo0 and fxp0 interfaces in the list of
RSVP interfaces because they do not carry labeled traffic. Also, as with MPLS, it is
considered good practice to disable RSVP on the fxp0 interface. Use the following
command to verify the configuration:
aviva@R1> show configuration protocols rsvp
interface so-0/0/2.0;
interface fxp0.0 {
disable;
}
The show rsvp version command shows you whether RSVP is running on the router:
aviva@R1> show rsvp version
Resource ReSerVation Protocol, version 1. rfc2205
RSVP protocol
= Enabled
R(refresh timer)
= 30 seconds
K(keep multiplier) = 3
Preemption
= Normal
Soft-preemption cleanup = 30 seconds
Graceful deletion timeout = 30 seconds
Graceful restart
= Disabled
Restart helper mode
= Enabled
Maximum helper restart time = 20000 msec
Maximum helper recovery time = 180000 msec
Restart time
= 0 msec
The first line of the output shows that the JUNOS software is running RSVP Version
1 (defined in RFC 2205). The second line shows that RSVP is enabled on the router.
The remaining lines show the settings for various RSVP parameters, which are the
default values because we haven’t configured anything other than basic RSVP functionality
at this point. The refresh timer of 30 seconds determines how often RSVP
sends periodic messages to its neighbors. The JUNOS software multiplies this value
by 1.5 and sends RSVP messages every 45 seconds by default. The keep multiplier
indicates the number of RSVP messages that can be lost on a connection before the
software considers an RSVP state to be stale.
The fifth line, Preemption, shows the default session preemption type of Normal.
RSVP uses preemption to accommodate additional sessions when a link does not
have sufficient bandwidth to carry all sessions. Normal preemption means that only
new better-priority RSVP sessions can preempt existing ones. (Recipe 14.14 explains
how to modify the default preemption behavior.) Normally, sessions are torn down
immediately when they are preempted. However, if soft preemption is configured,
RSVP attempts for 30 seconds to establish a new session before tearing down the
existing one. This is called soft-preemption cleanup. As part of tearing down an LSP,
by default, RSVP waits 30 seconds to gracefully time out the session. The last five
lines apply to graceful restart, which is disabled on the router.
Next, check that RSVP is up and running on the router’s interfaces. Here’s the output
for the ingress router:
506 | Chapter 14: MPLS
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