C H A P T E R
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
57-1
Cisco MDS 9000 Family CLI Configuration Guide
OL-16184-01, Cisco MDS SAN-OS Release 3.x
57
Configuring Port Tracking
The port tracking feature is unique to the Cisco MDS 9000 Family of switches. This feature uses
information about the operational state of the link to initiate a failure in the link that connects the edge
device. This process of converting the indirect failure to a direct failure triggers a faster recovery process
towards redundant links. 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.
This chapter includes the following sections:
•
About Port Tracking, page 57-1
•
Port Tracking, page 57-2
•
Displaying Port Tracking Information, page 57-6
•
Default Port Tracking Settings, page 57-8
About Port Tracking
Generally, hosts can instantly recover from a link failure on a link that is immediately (direct link)
connected 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 (see the
“Common Information
Model” section on page 29-1
and
“About RSCN Information” section on page 26-8
).
In
Figure 57-1
, when the direct link 1 to the host fails, recovery can be immediate. However, when the
ISL 2 fails between the two switches, recovery depends on TOVs, RSCNs, and other factors.
