Installation Guide

Table Of Contents
Auto-tuning links
Links brought down by CRC bursts and slow rate CRC receive auto-tuning before fabric link monitoring shuts down those links.
Auto-tuning links for burst CRC
Auto-tuning software will attempt to tune a link that is brought down by hardware due to a CRC burst, and when a slow rate CRC is
encountered, before fabric link monitoring shuts down that link. This enhancement will use existing fabric link monitoring syslog, SFM log
and SNMP trap messages for links shutdown or links powered down.
There are two instances when auto-tuning for a link is triggered:
Slow rate CRCs are encountered.
Burst CRCs are encountered.
NOTE
The feature for auto-tuning links for burst CRC was introduced in release 5.7.
Software sends a syslog/trap when auto-tuning is started and completed. This feature will utilize existing slow rate CRC auto tuning
syslog and SFM logs.
In the case where slow rate CRCs are encountered, triggering fabric link monitoring, the CRC error counter of each link is polled for every
monitoring period as follows:
If the total CRC errors in monitoring period pass, slow rate CRC monitoring will start auto-tuning that particular link, instead of
shutting down the link.
If the tuning algorithm returns an error, or if the software attempts to start auto-tuning links that are already-tuned, software
performs one of the following actions:
Link is powered down, sending a syslog and trap.
Link is not powered down, sending a syslog and trap (depending on the sysmon link configuration).
In slow rate CRC monitoring, link monitoring polls the CRC error counter of each link for every monitoring period. If the total CRC errors
in monitoring period pass, link monitoring will start auto-tuning that particular link instead of shutting down the link.
Auto-tuning CLI commands
This topic covers the steps for executing the sysmon fe auto-tune and sysmon tm auto-tune for enabling or disabling auto-
tuning on FE and TM for burst CRC.
Log into your system.
The following CLI steps will enable or disable auto-tuning on FE and TM for burst CRC.
1. Execute the CLI command [no] sysmon fe auto-tune.
device(config)#sysmon fe auto-tune
Event type already enabled.
Enables or disables auto-tuning on FE for burst CRC.
NOTE
Default: Enabled.
2. Execute the CLI command [no] sysmon tm auto-tune.
device(config)#sysmon tm auto-tune
Event type already enabled.
Product Overview
Brocade NetIron MLXe Series Hardware Installation Guide
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