If you use LMS/backup-LMS, the AP will connect to the LMS first and failover to the backup-LMS if the LMS is not available.
Also, if the firmware on the AP is different from the LMS it connects to, the AP will upgrade/downgrade to whatever version is on the controller it connects to, then reboot. After reboot, the controller discovery happens and firmware is up/downgraded to the firmware of the discovered controller. As you can imagine, having different firmware on the LMS and backup LMS can result in APs bouncing between controllers and versions, and you should carefully prepare the upgrade to minimize downtime.
With Mobility Conductor (AOS8) you can do a live upgrade that takes care of the controller upgrades, AP moves between controllers and running the upgrade such that not all APs in a single place reboot at the same time, so if you have enough coverage, clients probably will not notice the upgrade. So that would be the recommended way to upgrade, but you don't have a Mobility Conductor.
There is quite some material out, and your Aruba partner or Aruba support should be able to assist you in validating your upgrade path, or even design the upgrade path. This goes beyond what normally can be done in a forum as there is really limited information specific to your deployment.
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Herman Robers
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If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
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Original Message:
Sent: May 23, 2023 01:58 PM
From: joaomir@hotmail.com
Subject: Upgrade standalone wireless controller - what happens to APs
Hi all,
I manage an infrastructure that is composed by a cluster of Mobility Masters v8, that manage 2 standalone mobility controllers v8, each with 100 APs.
The controllers are not part of a cluster but the APs use LMS-backup to find the controller and also for redundancy. If one controller goes down, the APs reregister in the other controller.
I need to upgrade all the equipment, either with a major or minor upgrade.
Maintaing the WIfi service online is critical as we're talking about a 24/7 customer.
What will happen to each ser of APs after I upgrade one of the controllers? Will they start upgrading and rebooting? Will they jump to the other controller?
How long will the upgrade process take?
Thanks very much for your help, I never upgraded AOS8 before.
BR