doc: improve documentation of the IS-IS fast reroute commands

* Clarify which commands are applicable to which flavors of LFA;
* Explain the default prefix priority for different prefix types;
* Rearrange some command descriptions so that they appear in this
  order: local LFA, remote LFA and then TI-LFA.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
This commit is contained in:
Renato Westphal 2021-02-25 14:40:34 -03:00
parent ca7b6587b2
commit f691f2ebbd

View File

@ -121,17 +121,23 @@ ISIS Timer
ISIS Fast-Reroute
=================
Unless stated otherwise, commands in this section apply to all LFA
flavors (local LFA, Remote LFA and TI-LFA).
.. clicmd:: spf prefix-priority [critical | high | medium] WORD
Assign a priority to the prefixes that match the specified access-list.
By default loopback prefixes have medium priority and non-loopback prefixes
have low priority.
.. clicmd:: fast-reroute priority-limit [critical | high | medium] [level-1 | level-2]
Limit LFA backup computation up to the specified prefix priority.
.. clicmd:: fast-reroute lfa tiebreaker [downstream | lowest-backup-metric | node-protecting] index (1-255) [level-1 | level-2]
Configure a tie-breaker for multiple LFA backups. Lower indexes are
Configure a tie-breaker for multiple local LFA backups. Lower indexes are
processed first.
.. clicmd:: fast-reroute load-sharing disable [level-1 | level-2]
@ -140,8 +146,8 @@ ISIS Fast-Reroute
.. clicmd:: fast-reroute remote-lfa prefix-list [WORD] [level-1 | level-2]
Configure a prefix-list to select eligible PQ nodes (valid for all protected
interfaces).
Configure a prefix-list to select eligible PQ nodes for remote LFA
backups (valid for all protected interfaces).
.. _isis-region:
@ -239,15 +245,11 @@ ISIS interface
.. clicmd:: isis fast-reroute lfa [level-1 | level-2]
Enable per-prefix LFA fast reroute link protection.
Enable per-prefix local LFA fast reroute link protection.
.. clicmd:: isis fast-reroute lfa [level-1 | level-2] exclude interface IFNAME
Exclude an interface from the LFA backup nexthop computation.
.. clicmd:: isis fast-reroute ti-lfa [level-1|level-2] [node-protection]
Enable per-prefix TI-LFA fast reroute link or node protection.
Exclude an interface from the local LFA backup nexthop computation.
.. clicmd:: isis fast-reroute remote-lfa tunnel mpls-ldp [level-1 | level-2]
@ -259,6 +261,10 @@ ISIS interface
Limit Remote LFA PQ node selection within the specified metric.
.. clicmd:: isis fast-reroute ti-lfa [level-1|level-2] [node-protection]
Enable per-prefix TI-LFA fast reroute link or node protection.
.. _showing-isis-information: