CLI Reference Guide-R04

Chapter 21 | 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 instance 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 instance instance-name {east | west}
instance-name - Name of a specific ERPS instance. (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:
WTB Expires local |
WTB Running local |
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 99: ERPS Request/State Priority (Continued)
Request / State and Status Type Priority