Fspf Global Configuration; About Spf Computational Hold Times; About Link State Records - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Configuring Fibre Channel Routing Services and Protocols
failure of a link in a SAN port channel does not trigger a route change, which reduces the risks of routing
loops, traffic loss, or fabric downtime for route reconfiguration.
Figure 70: Fault Tolerant Fabric with Redundant Links
For example, if all links are of equal speed and no SAN port channels exist, the FSPF calculates four equal
paths from A to C: A1-E-C, A2-E-C, A3-D-C, and A4-D-C. If SAN port channels exist, these paths are reduced
to two.

FSPF Global Configuration

By default, FSPF is enabled on switches in the Cisco Nexus 5000 Series .
Some FSPF features can be globally configured in each VSAN. By configuring a feature for the entire VSAN,
you do not have to specify the VSAN number for every command. This global configuration feature also
reduces the chance of typing errors or other minor configuration errors.
FSPF is enabled by default. Generally, you do not need to configure these advanced features.
Note
Caution The default for the backbone region is 0 (zero). You do not need to change this setting unless your region
is different from the default. If you are operating with other vendors using the backbone region, you can
change this default to be compatible with those settings.

About SPF Computational Hold Times

The SPF computational hold time sets the minimum time between two consecutive SPF computations on the
VSAN. Setting this to a small value means that FSPF reacts faster to any fabric changes by recomputing paths
on the VSAN. A small SPF computational hold time uses more switch CPU time.

About Link State Records

Each time a new switch enters the fabric, a link state record (LSR) is sent to the neighboring switches, and
then flooded throughout the fabric.
The following table displays the default settings for switch responses.
OL-16597-01
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
FSPF Global Configuration
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