5760 HA not syncing after reboot with possible config mismatch

[pwilliams86]

Hi,

We have an old pair of 5760 WLCs (am aware that they are nearing or reached end-of-sale, support, life etc), the 'primary' had memory issues and the only way to get it to failover to the redundant pair was to pull the power on the failing unit. The failover worked fine, there was no downtime, but now the unit that I had to reboot will not rejoin the pair.

Syslog shows this message

Received reload request for switch 1, reason Bulk Sync Failure

Research into that syslog message pointed to a config mismatch between the controllers and on the current live 5760 i get

WLC01#sh redundancy config-sync failures prc
PRC Failed Command List
-----------------------
-ap dot11 24ghz rate RATE_6M disable
-ap dot11 24ghz rate RATE_9M disable

I have taken the failing unit out of the stack and powered it on independently and looked at the config and those two lines of config are missing.

Commands from the current live 5760

WLC01#sh run
ap dot11 24ghz rrm channel device
no ap dot11 24ghz rrm coverage
ap dot11 24ghz cleanair
ap dot11 24ghz beamforming
no ap dot11 24ghz dot11g
ap dot11 24ghz rate RATE_1M disable
ap dot11 24ghz rate RATE_2M disable
ap dot11 24ghz rate RATE_5_5M disable
ap dot11 24ghz rate RATE_6M disable
ap dot11 24ghz rate RATE_9M disable
ap dot11 24ghz rate RATE_11M mandatory
ap dot11 24ghz rate RATE_12M supported
ap dot11 24ghz rate RATE_18M supported
ap dot11 24ghz rate RATE_24M supported
ap dot11 24ghz rate RATE_36M supported
ap dot11 24ghz rate RATE_48M supported
ap dot11 24ghz rate RATE_54M supported
ap dot11 24ghz l2roam rf-params custom -80 3 -72 5
WLC01#

And then from the failing 5760

WLC01#sh run
ap dot11 24ghz rrm channel device
no ap dot11 24ghz rrm coverage
ap dot11 24ghz cleanair
ap dot11 24ghz beamforming
no ap dot11 24ghz dot11g
ap dot11 24ghz rate RATE_1M disable
ap dot11 24ghz rate RATE_2M disable
ap dot11 24ghz rate RATE_5_5M disable
ap dot11 24ghz rate RATE_11M mandatory
ap dot11 24ghz rate RATE_12M supported
ap dot11 24ghz rate RATE_18M supported
ap dot11 24ghz rate RATE_24M supported
ap dot11 24ghz rate RATE_36M supported
ap dot11 24ghz rate RATE_48M supported
ap dot11 24ghz rate RATE_54M supported
ap dot11 24ghz shutdown - I have to shut this down to make any changes above
ap dot11 24ghz l2roam rf-params custom -80 3 -72 5
WLC01#

I have tried adding those two lines to the config but the controller doesnt take it. I have disabled the 2.4Ghz radio prior to putting in the command so it isnt that. 

WLC01(config)#ap dot11 24ghz rate rate_6M disable
% switch-1:wcm:Invalid parameters specified.

I can add the 6M (and 9M) rate line if I use supported or mandatory instead of disable so I need help to find out why it wont take the disable command.

Many thanks for any help,

P

[marce1000]

            WLC01(config)#ap dot11 24ghz rate rate_6M disable
                      % switch-1:wcm:Invalid parameters specified.

  - Don't know which controller version(s) is/are being used : this could be a bug 

             https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvj73809/?rfs=iqvred

 M.

[pwilliams86]

Thank you for this, the bug solution was to try doing the same from the GUI. I tried that and it still didnt work. In the end the WLC fell over completely and the reboot made the primary back to being the primary. I think the problem is still there should there be a failover again, the primary will not return to the HA pair, but options are limited when you use old kit,

Thanks again,

P