Configuring Congestion Isolation; Configuring Extended Receiver Ready - Cisco MDS 9000 Series Configuration Manual

Congestion Detection, Avoidance, and Isolation
The 1 second (F ports) and 1.5 seconds (E ports) timers that are set for the switch to initiate CLR are fixed
and cannot be changed.
To verify a port monitor policy to generate SNMP alerts and take other actions in the quantity and timing of
these events, perform these steps:
Step 1
Display the last 10 credit loss events per interface per module:
switch# show process creditmon credit-loss-events [module x]
Step 2 Display a chronological log of credit loss events per module:
switch# show process creditmon credit-loss-event-history [module x]
When a port sees the credit loss condition and fails to recover, the port flaps. This function is already a part of
Note
the portguard, and you can configure the supported actions using the Portguard feature.

Configuring Congestion Isolation

The Congestion Isolation feature allows slow devices to be put into their own virtual link automatically as
the port monitor detects the slow-drain condition.
The following port-monitor counters are used to detect slow drain and isolate the devices on an interface.
• credit-loss-reco
• tx-credit-not-available
• tx-slowport-oper-delay
• txwait
Configure the Slow-Drain Device Detection and Congestion Isolation feature in the following sequence:
1. Configure the Extended Receiver Ready feature. For more information, see
Ready, on page
2. Configure the Congestion Isolation feature. For more information, see
page
3. Configure a port-monitor policy with one or more counters containing the portguard action cong-isolate.
For more information, see
page

Configuring Extended Receiver Ready

Enabling Extended Receiver Ready
To enable Extended Receiver Ready (ER_RDY) on a switch, perform these steps:
177.
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Configuring the Port-Monitor Portguard Action for Congestion Isolation, on
180.
Cisco MDS 9000 Series Interfaces Configuration Guide, Release 8.x
Configuring Congestion Isolation
Enabling Extended Receiver
Enabling Congestion Isolation, on
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