When an Etherchannel has been configured on AIX, using a primary and a backup adapter for failover purposes, it is possible to force a failover between these adapters.

To do this, first check what the currently active adapter is within the Etherchannel. For example, if the Etherchannel is called ent4, run:

# entstat -d ent4 | grep "Active channel"
Active channel: backup adapter

As you can see, the Etherchannel is currently active on the backup adapter. To see the defined adapters for both primary and backup, run:

# lsattr -El ent4

Now, force it to fail over to the primary adapter:

# /usr/lib/methods/ethchan_config -f ent4

Please note that it is best to run this command from the console, as you may temporarily lose network connectivity when the Etherhannel is failing over. You may also notice messages being logged in the error report by running the errpt command in the form of "ETHERCHANNEL FAILOVER".

Now run the entstat command again to determine the active channel:

# entstat -d ent4 | grep "Active channel"
Active channel: primary channel

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