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    <title>Information About Port Tracking </title>
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<a name="wp1158128"> </a><h1 class="pTitle">
Information About Port Tracking

</h1>
<a name="wp1158129"> </a><p class="pBody">
The Port Tracking feature is unique to the Cisco MDS 9000 Family of switches. This feature uses 
informtion about the operational state of the link to initiate a failure in the link that connects the edge 
device. This prcess of converting the indirect failure to a direct failure triggers a faster recovery process 
towards redu dant links. Generally, hosts can instantly recover from a link failure on a link that is 
immediately (direct link) conected to a switch. However, recovering from an indirect link failure 
between switches in a WAN or MAN fabric with a keep-alive mechanism is dependent on several factors 
such as the time out values (TOVs) and on registered state change notification (RSCN) information. 
When enabled, the port tracking feature brings down the configured links based on the failed link and 
forces the traffic to be redirected to another redundant link.

</p>
<a name="wp1158130"> </a><p class="pBody">
The port tracking feature is disabled by default in all switches in the Cisco 9000 Family. When you 
enable this feature, port tracking is globally enabled for the entire switch.

</p>
<hr /><br><p class="pBody">Copyright 2010-2013, Cisco Systems, Inc. All rights reserved.</p> 

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