WLC 5508 - Replace Primary Unit in HA Pair

[ckendzora]

Hi,

I have two WLC 5508 controllers running in SSO HA Pair.  The primary unit crashed and lost all config, license, and image files.  The failover to secondary was successful and now it is running as secondary (active).  The secondary unit is HA-SKU license.

I received the replacement primary through RMA and am looking for the correct replacement steps.  I found a cisco document that seems to show the exact method for replacement but I have been told by separate TAC engineers two different methods from the document, both of which require full downtime and extra steps.  Can anyone clue me in to the correct method for replacing the primary unit in HA pair?

Thank you

Add Additional Licenses on the HA Pair and Replace WLC While in HA Setup Configuration Example

Replace the Primary WLC in HA Setup

The primary WLC was affected and the user must replace it. The secondary WLC is up and all APs are attached to it. The new WLC received return material authorization (RMA) can be added with one of the failed WLCs in the HA pair. Follow the steps in this section in order to understand how to replace a WLC in active setup.

1. Make sure that the first WLC is the same version as the other WLC.
2. Configure the WLC with the same subnet management IP addresses as the previous WLC.
3. Configure the new WLC with HA configuration that includes redundant management, IP address, and peer primary. Enable the AP SSO.
4. When the AP SSO is enabled, it reboots. While it reboots, the AP SSO discovers the current active secondary, syncs the configuration, and transitions to a hot standby state.

Note: You do not need to break the HA configuration on the current active WLC or reboot the current active WLC. The configuration will be synced with the current active WLC.

[sremk · Accepted solution]

The above-mentioned steps are correct. After that, you can make the primary(replaced controller) to active. So that we can make sure the secondary controller (HA-SKU) is not the active as it is supposed to be the secondary always and should be active only when the primary fails.

Thanks

Sreejith

[ckendzora]

Thank you.  You were able to confirm the correct upgrade procedure when two Cisco TAC engineers could not.  I perfomed the replacement following the steps in my original post.  Here are my notes from the procedure:

1. Update code on the replacement primary to match active secondary
2. Migrate base AP count license from RMA primary to replacement primary
   1. License Administration Portal
   2. Devices Tab
      1. Move Licenses drop box -- rehost from failed device (RMA)
3. Configure mgmt, redundancy mgmt, redundancy peer
   1. The two redundancy addresses should be identical to the ones from the failed primary.  The mgmt address should be an unused IP in the same network as the secondary mgmt.  Once they pair the primary will pull config from secondary and use that mgmt address
4. Connect redundancy ports together on primary/secondary.  Connect the network ports.
5. config redundancy mode sso on primary
6. The primary will reboot to enable sso and pull the config from the current active (secondary in this case) unit xml on boot.
7. Once config is bulk-synced the primary unit is now in HOT STANDBY
8. Redundancy force-switchover
9. Done
10. Make sure to check your mobility group as the new pair will use the MAC address from the replacement primary and not the active secondary.  You can either use config redundancy mac <MAC> on the replacement primary to use the custom MAC you have already configured on your mobility groups.  If you do not do this it cannot be changed after pairing.  Then you will have to update the mobility groups themselves with the new mobility MAC from the HA pair.

[BenBen]

Hi  ckendzora,

Thanks for the very detailed steps and the capture of the observations. Looking at your steps, this seems to be a procedure without interrupt to the wireless services. Is that correct?

Thanks.

[Carlos Rogério S. Santos]

Thank you for sharing your experience with us after the move.

I appreciate

[c-davies]

Hello,

Cany anyone advise, what happens to the licences? Do they get transferred back from the secondary to the primary? Do I need to action the RTU licences on the primary?

Thanks

[Scott Fella]

You have a 5508, so if you are going to rma that, TAC will provide you a pak so you can register the license to the new unit. The secondary 5508 either in SSO or configured as secondary unit will take over the license.
You should also state how your setup is. SSO, N+1, etc. because we have to guess the possible outcomes.

[Carlos Rogério S. Santos]

Good afternoon dear

Just come across this problem and I have already found the solution.

Thank you all

[Aleck_Sei]

Hello everyone,

Taking advantage of this thread, what would be the steps to follow in the event that the unit to be replaced due to a breakdown was the Secondary/Standby one? We have a couple of 8540 in SSO HA.

Thank you very much to all

[ckendzora]

jr,

I think you can follow my directions and swap the words primary and secondary.  The outlined steps will be the same but you are performing most of them to the secondary/standby device instead of the primary/standby device as I did above.

[Aleck_Sei]

Thank you for your answer, ckendzora

That is, is it not necessary to configure any default route on the new controller?