26-16
Ethernet Card Software Feature and Configuration Guide, R7.2
January 2009
Chapter 26 Configuring IEEE 802.17b Resilient Packet Ring
Configuring Triggers for CRC Errors
To enable and configure the triggers for CRC errors, perform the following procedure, beginning in
global configuration mode:
Command Purpose
Step 1 Router(config)# interface rpr-ieee 0 Activates interface configuration mode to
configure the RPR-IEEE interface.
Step 2 Router(config-if)# trigger crc-error
threshold crc-error-rate {east | west |
<cr>}
Configures the threshold for the CRC errors on the
RPR-IEEE span. The threshold is the percentage
of received, continously CRC-errored frames
required during the delay period (soak time).
When the threshold is crossed, the excessive crc
alarm is declared. This also triggers the CRC error
action, if one is configured.
For crc-error-rate, specify the CRC packet
error rate variable in the range from 2 to 4. The
error rate variable corresponds to the CRC error
rate as a percentage of traffic.
2 is 10e-2 or 1% of traffic (1 CRC error in100
frames).
3 is 10e-3 or 0.1% of traffic. (1 CRC error
in1000 frames).
4 is 10e-4 or 0.01% of traffic (1 CRC error
in10000 frames).
The default threshold is 3.
(Optional) You can also specify the east or west
ringlet.
Step 3 Router(config-if)# trigger crc-error action
{east | west | <cr>}
Specifies whether excessive CRC errors shut down
the span. The default is for excessive CRC errors
not to shut down the span.
(Optional) You can also specify the east or west
ringlet.
Caution The user must configure both spans to
shut down on receiving excessive CRC
errors. With the default behavior of both
spans not shutting down, network
problems can occur if the ML-Series
card receives signal degrade (SD) while
in passthrough mode.
Step 4 Router(config-if)# trigger crc-error delay
soak-minutes {east | west | <cr>}
(Optional) Sets the number of minutes that CRC
errors must exceed the threshold (soak) before an
action is taken. For soak-minutes, the range is
from 3 minutes to 10 minutes. The default is 10
minutes.
(Optional) You can also specify the east or west
ringlet.