Alcatel-Lucent 7450 Manual page 136

Shared Risk Link Groups
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Page 136
→ Configure primary and secondary LSP paths and enable SRLG on the secondary LSP
path. Note that the SRLG secondary LSP path(s) will always perform a strict CSPF
query. The srlg-frr command is irrelevant in this case (see
For FRR detours/bypass SRLG disjoint configuration:
→ Create an SRLG group, similar to admin groups.
→ Link the SRLG group to MPLS interfaces.
→ Enable the srlg-frr (strict/non-strict) option, which is a system-wide parameter, and it
force every LSP path CSPF calculation, to take the configured SRLG membership(s)
(and propagated through the IGP opaque-te-database) into account.
→ Configure primary FRR (one-to-one/facility) LSP path(s). Consider that each PLR
will create a detour/bypass that will only avoid the SRLG membership(s) configured
on the primary LSP path egress interface. In a one-to-one case, detour-detour merging
is out of the control of the PLR, thus the latter will not ensure that its detour will be
prohibited to merge with a colliding one. For facility bypass, with the presence of
several bypass type to bind to, the following priority rules will be followed:
1. Manual bypass disjoint
2. Manual bypass non-disjoint (eligible only if srlg-frr is non-strict)
3. Dynamic disjoint
4. Dynamic non-disjoint (eligible only if srlg-frr is non-strict)
Non-CSPF manual bypass is not considered.
srlg-frr on page 221).
7450 ESS MPLS Guide