Bandwidth Fairness; Upgrade Or Downgrade Scenario - Cisco MDS 9000 Series Configuration Manual

Bandwidth Fairness

Caution
If you need to bring an interface back into service, you might disrupt traffic if you need to release shared
resources from other interfaces in the same port group.
Bandwidth Fairness
This feature improves fairness of bandwidth allocation among all ports and provides better throughput average
to individual data streams. Bandwidth fairness can be configured per module.
Caution
When you disable or enable bandwidth fairness, the change does not take effect until you reload the module.
Use the show module bandwidth-fairness command to check whether ports in a module are operating with
bandwidth fairness enabled or disabled.
switch# show module 2 bandwidth-fairness
Module 2 bandwidth-fairness is enabled

Upgrade or Downgrade Scenario

When you are upgrading from a release earlier than Cisco SAN-OS Release 3.1(2), all modules operate with
bandwidth fairness disabled until the next module reload. After the upgrade, any new module that is inserted
has bandwidth fairness enabled.
When you are downgrading to a release earlier than Cisco SAN-OS Release 3.1(2), all modules keep operating
in the same bandwidth fairness configuration prior to the downgrade. After the downgrade, any new module
that is inserted has bandwidth fairness disabled.
Note After the downgrade, any insertion of a module or module reload will have bandwidth fairness disabled.
Cisco MDS 9000 Series Interfaces Configuration Guide, Release 8.x
84
Configuring Fibre Channel Interfaces