Replacing 8510 WLC in an HA pair environment

[reinier]

Hello,

I recently had an 8510 fail that was the primary in an HA pair.  I have received my replacement and I am about to replace the defective unit.  Has anyone had to perform this operation before?  Did the new Primary unit inherit the settings from the Secondary unit?  What did you do about licensing?

Thank you!

[Leo Laohoo · Accepted solution]

Did the new Primary unit inherit the settings from the Secondary unit?

Yes.  

Configure the replacement unit with the same method as configuring a brand-new controller:  Management IP address and Redundant IP address are important.  Configure the peer and enable HA.  Don't forget to specify if the replacement unit is the primary or secondary unit.  

Another thing, don't forget to update the firmware of the controller to match the on-line unit.  

What did you do about licensing?

Contact Cisco TAC and ask them to port the license from the defective unit to the replacement unit.

[reinier]

Thank you.  I am assuming that I should change the Secondary to Primary before adding the replacement.  I would hate for the new unit to act as Primary and wipe all the configuration that has already happened... or is the HA activation smart enough to know that the secondary unit has the config?

[Leo Laohoo]

or is the HA activation smart enough to know that the secondary unit has the config?

It is smart enough because HA will look at who's got the HA license.  Play it safe, save the config and export the config out to a text file.  

If the replacement unit is the Primary, then I'd configure it accordingly as so.