ECS4110-28T_Management Guide

C HAPTER 36 | ERPS Commands
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◆ Recovery for forced switching under revertive and non-revertive mode
is described under the Command Usage section for the non-revertive
command.
◆ When a ring is under an FS condition, and the node at which an FS
command was issued is removed or fails, the ring remains in FS state
because the FS command can only be cleared at node where the FS
command was issued. This results in an unrecoverable FS condition.
When performing a maintenance procedure (e.g., replacing, upgrading)
on a ring node (or a ring link), it is recommended that FS commands be
issued at the two adjacent ring nodes instead of directly issuing a FS
command at the ring node under maintenance in order to avoid falling
into the above mentioned unrecoverable situation.
EXAMPLE
Console#erps forced-switch domain r&d west
Console#
erps manual-switch This command blocks the specified ring port, in the absence of a failure or
an erps forced-switch command.
SYNTAX
erps manual-switch [domain ring-name] {east | west}
ring-name - Name of a specific ERPS ring. (Range: 1-12 characters)
east - East ring port.
west - West ring port.
COMMAND MODE
Privileged Exec
COMMAND USAGE
◆ A ring with no request has a logical topology with the traffic channel
blocked at the RPL and unblocked on all other ring links. In this
situation, the erps manual-switch command triggers protection
switching as follows:
a. If no other higher priority commands exist, the ring node, where a
manual switch command was issued, blocks the traffic channel and
R-APS channel on the ring port to which the command was issued,
and unblocks the other ring port.
R-APS (NR, RB) remote |
R-APS (NR) remote lowest
* If an Ethernet Ring Node is in the Forced Switch state, local SF is ignored.
Table 140: ERPS Request/State Priority (Continued)
Request / State and Status Type Priority