Owner's Manual

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constrained-path computation is enabled; that is, for which the no-cspf statement is not
configured. To avoid extensive resource consumption that might result because of frequent
path recomputations, or to avoid destabilizing the network as a result of constantly changing
LSPs, best practice is either to leave the timer value sufficiently large or to disable the timer
value. By default, the optimize timer is disabled.
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Preference —Preference for the route. You can optionally configure multiple LSPs between the
same pair of ingress and egress routers. This is useful for balancing the load among the LSPs
because all LSPs, by default, have the same preference level. To prefer one LSP over another,
set different preference levels for individual LSPs. The device uses the LSP with the lowest
preference value. The default preference for LSPs is lower (more preferred) than all learned
routes except direct interface routes. Range: 1 through 255. Default: 5 for static MPLS LSPs,
7 for RSVP MPLS LSPs, 9 for LDP MPLS LSPs
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Setup Priority —If, at session setup time, insufficient link bandwidth is encountered during
session establishment, the setup priority is compared with existing established sessions on the
link to determine whether some of them should be preempted to accommodate the new
session. The session with the lower hold priority is preempted. Range: 0 through 7, where 0 is
the highest and 7 is the lowest priority. Default: 7 (The session cannot preempt any existing
sessions.).
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Hold Priority —Hold priority, used to keep a reservation after it has been set up. A smaller
number has a higher priority. The priority must be greater than or equal to the setup priority
to prevent preemption loops. Range: 0 through 7, where 0 is the highest and 7 is the lowest
priority. Default: 0 (Once the session is set up, no other session can preempt it.).
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Revert Timer —Specify the amount of time (in seconds) that an LSP must wait before it can
revert traffic back onto a primary path. If during this time the primary path experiences any
connectivity problem or stability problem, the timer is restarted. If you have configured a
value of 0 seconds for the revert-timer statement and traffic is switched to the secondary path,
the traffic remains on that path indefinitely. It is never switched back to the primary path
unless you intervene. Range: 0 through 65,535 seconds. Default: 60 seconds.
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RSVP Hold Time —Amount of time MPLS retains RSVP PathErr messages and considers them
for CSPF computations. The more time you configure, the more time a source node (ingress
of the RSVP LSPs) can have to learn about the failures of its LSP by monitoring PathErr
messages transmitted from downstream nodes. Information from the PathErr messages is
incorporated into subsequent LSP computations, which can improve the accuracy and speed
of LSP setup. Some PathErr messages are also used to update traffic engineering database
(TED) bandwidth information, reducing inconsistencies between the TED and the network.
Range: 0 through 240 seconds. Default: 25 seconds.
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Traffic Engineering —Select whether MPLS performs traffic engineering on BGP destinations
only or on both BGP and IGP destinations. Affects only LSPs originating from this router, not
transit or egress LSPs. Options:
BGP destinations only—Ingress routes are installed in the inet.3 routing table.