How to upgrade both WLC configured in HA

[Sam Caprio]

Hello team,

I need to upgrade both the standby and active WLCs using the CLI. However, I couldn't find the method to upgrade the standby WLC via CLI in the official Cisco documentation. Could you please share the procedure? I believe the standby WLC has a limited set of accepted CLI commands and has no GUI, so I want to confirm how to transfer the image to the standby WLC and perform the upgrade via CLI.

Additionally, since I have to upgrade both WLCs (active and standby) individually, won't there be a version mismatch after upgrading the first one? Could this mismatch affect the HA setup?

I am working with 9800 WLCs configured in HA mode (active and standby) that manage over 1,000 APs. What is the recommended approach to upgrade the software in this setup?

[Flavio Miranda]

@Sam Caprio 

 You dont upgrade WLC in HA individually. Gets familiar with Software Maintenance Updates  and you will be fine

 https://www.cisco.com/c/dam/en/us/td/docs/wireless/controller/9800/17-3/deployment-guide/c9800-ha-rau-apsp-apdp-issu-dg-rel-17-3.pdf

[balaji.bandi]

What code running on WLC 9800 - recently did a one more upgrade with same kind of controller with more than the size of the AP.

seamless ISSU upgrade. make sure you select the ROLLING upgrade AP 15% or more depends on the Environment.

Took around 3-4 hours whole process, while upgrade not noticed any issue with client connection at all.

Key take away from that upgrade :

1. Config backup out of box.

2. Make sure you able to failover and smooth before upgrade.

3. check any Mobility anchors before upgrade.

4. Give enough time for the Upgrade and be patient.

Last make sure you understand the upgrade and release notes. check any caveats that effect your environement or AP Upgrade.

I have document high level steps :

https://www.balajibandi.com/?p=2272

[MHM Cisco World]

https://goodwi.fi/posts/2019/08/upgrading-cisco-9800-in-ha/

Check this 

MHM

[Sam Caprio]

Hello MHM,

I reviewed the document shared by you.
After the install activate command, the controller will reload.

Post controller reload, the APs preload primary downloaded image will activiated automatically or a AP reboot is required?

Is there a recommended way for upgrading 1500 APs which is connected to this controller?

[Leo Laohoo]

Please confirm if this is HA SSO or N+1. 

What is the intended version to upgrade to? 

What is the exact model of the WLC, is it a 9800-L, 9800-40, 9800-80 or 9800X?

Finally, please be mindful of CSCwj73634.

FN74222 - Full or Partial Cisco 9800 Series Wireless Controller Configuration Loss after High-Availability Stateful Switchover Failover

[Sam Caprio]

It is HA SSO
We are upgrading to version 17.9.5
It is 9800-80 controller

The best recommended CLI way to upgrade the WLC 9800 - 80. We have 1500 APs connected to it.

Also if we predownload and swap new image to AP then Post controller reload, the APs preload primary downloaded image will activiated automatically or a AP reboot is required?

[Leo Laohoo]

There are several ways of upgrading the firmware of a 9800-40/-80 and one of those is about the question of "WHEN"  to reboot the controller, immediately or some time in the future.

[Haydn Andrews]

If controller configured as SSO - just upgrade the primary it will automatically upgrade the standby.

If in N+1 then upgrade secondary and then the primary

Also make sure you follow the release notes and TAC recommended releases and upgrade the ROMMON - seen heaps of issues if this is not followed

[Rich R]

Great to hear that @balaji.bandi was able to use ISSU but many of us have had problems trying to use ISSU.  I would say >50% possibility of upgrade going wrong if you use ISSU.  Best to have TAC online with you while upgrading with ISSU in case it goes wrong because you'll need their help to fix it (usually involves multiple reloads).  We prefer to use non-ISSU upgrade, after hours, and take a short hit for 5-10 minutes while they both reload.  This also means the upgrade completes much quicker.

[balaji.bandi]

@Rich R  - had 2 success so far. (this impressed honest) - but problem with 1 hit was, all the AP need to reload, that may not like kind of environment i work. so that 15% AP reboot worked as expected.

I have another big one coming in week, bigger than other one, let you know same steps i am going to use but more AP and higher model of WLC.

[Leo Laohoo]

We are planning to upgrade two 9800-80 (N+1) to 17.12.4, install 2 x SMU and 1 APSP. 

Best of all, this will all be happening in the middle of a business day to a 24x7 critical health site campus (3100 x APs and 10k wireless clients).  

Did I mention that we are doing a "no outage" change?

[balaji.bandi]

Did I mention that we are doing a "no outage" change?

That similar kind of site we are in 5x number of clients)

like you hear your story if this is not ISSU, then hit less upgrade with out any downtime, please share, i keep as alternative plan.

today same model SSO - with near by AP ISSU went as expected, now monitoring state..

[Leo Laohoo]

We will be using N + 1 Hitless Upgrade.  We've used this several times before with great success (except upgrading to 17.9.4a).  

AMA: Catalyst 9800 Upgrade & High Availability