About Persistent Fc Ids - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Configuring Domain Parameters
Step 3
FC IDs
When an N port logs into a Cisco Nexus 5000 Series switch, it is assigned an FC ID. By default, the persistent
FC ID feature is enabled. If this feature is disabled, the following situations can occur:
• An N port logs into a Cisco Nexus 5000 Series switch. The WWN of the requesting N port and the
• The switch is designed to preserve the binding FC ID to the WWN on a best-effort basis. For example,
• The volatile cache stores up to 4000 entries of WWN to FC ID binding. If this cache is full, a new (more
• N ports receive the same FC IDs if disconnected and reconnected to any port within the same switch (as

About Persistent FC IDs

When persistent FC IDs are enabled, the following occurs:
• The current FC IDs in use in the fcdomain are saved across reboots.
• The fcdomain automatically populates the database with dynamic entries that the switch has learned
If you connect to the switch from an AIX or HP-UX host, be sure to enable the persistent FC ID feature
Note
in the VSAN that connects these hosts.
Note When persistent FC IDs are enabled, FC IDs cannot be changed after a reboot. FC IDs are enabled by
default, but can be disabled for each VSAN.
A persistent FC ID assigned to an F port can be moved across interfaces and can continue to maintain the
same persistent FC ID.
OL-16597-01
Command or Action
switch(config)# no fcdomain
contiguous-allocation vsan vsan-id
assigned FC ID are retained and stored in a volatile cache. The contents of this volatile cache are not
saved across reboots.
if one N port disconnects from the switch and its FC ID is requested by another device, this request is
granted and the WWN with the initial FC ID association is released.
recent) entry overwrites the oldest entry in the cache. In this case, the corresponding WWN to FC ID
association for the oldest entry is lost.
long as it belongs to the same VSAN).
about after a device (host or disk) is plugged into a port interface.
Purpose
The contiguous-allocation option takes
Note
immediate effect at runtime. You do not need
to restart the fcdomain.
Disables the contiguous allocation option and reverts
it to the factory default in the specified VSAN.
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
FC IDs
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