ECS4110-28T_Management Guide

C HAPTER 36 | ERPS Commands
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When non-ERPS device protection is enabled on the ring, the ring ports
on the RPL owner node and non-owner nodes will not be blocked when
signal loss is detected by CCM loss events.
◆ When non-ERPS device protection is enabled on an RPL owner node, it
will send non-standard health-check packets to poll the ring health
when it enters the protection state. It does not use the normal
procedure of waiting to receive an R-APS (NR - no request) message
from nodes adjacent to the recovered link. Instead, it waits to see if the
non-standard health-check packets loop back. If they do, indicating
that the fault has been resolved, the RPL will be blocked.
After blocking the RPL, the owner node will still transmit an R-APS (NR,
RB - ring blocked) message. ERPS-compliant nodes receiving this
message flush their forwarding database and unblock previously
blocked ports. The ring is now returned to Idle state.
EXAMPLE
Console(config-erps)#non-erps-dev-protect
Console(config-erps)#
non-revertive This command enables non-revertive mode, which requires the protection
state on the RPL to manually cleared. Use the no form to restore the
default revertive mode.
SYNTAX
[no] non-revertive
DEFAULT SETTING
Disabled
COMMAND MODE
ERPS Configuration
COMMAND USAGE
◆ Revertive behavior allows the switch to automatically return the RPL
from Protection state to Idle state through the exchange of protocol
messages.
Non-revertive behavior for Protection, Forced Switch, and Manual
Switch states are basically the same. Non-revertive behavior requires
the erps clear command to used to return the RPL from Protection state
to Idle state.
◆ Recovery for Protection Switching – A ring node that has one or more
ring ports in an SF (Signal Fail) condition, upon detecting the SF
condition cleared, keeps at least one of its ring ports blocked for the
traffic channel and for the R-APS channel, until the RPL is blocked as a
result of ring protection reversion, or until there is another higher
priority request (e.g., an SF condition) in the ring.