Wireless Access

When configuring HA, I typically configure the LMS IP in the AP System Profile and let the Backup LMS be inherited from the HA configuration (DUAL mode). However, I have a customer that has the HA configuration AND LMS/Backup LMS configured. I have heard that this can cause issues with some APs, but don't know the specifics as to what issues. 

 

Could having both of these configured cause APs to reboot or have trouble coming up completely? We have APs that will randomly start rebooting and will show as UP for about 1m30s and then go back down. Random APs at different locations, fix has always been to just replace the AP with another, but would like to identify the root cause, this happens on a regular basis, but customer has over 2000 APs deployed across multiple controller clusters (Master/Local).

 

Running 6.3.1.16 w/ AP's 125, 135 and 225. Happens to all models.

You use the backup LMS in case you have double failure "The Controller and the AP"
When APs failover to the backup LMS
those APs will not build a standby tunnel until those fail back to the Primary LMS

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So if the AP loses communication to its LMS, and HA+backup LMS are configured, could that cause the reboot issue because the AP can't establish a new tunnel? This may be completely unrelated, but wanted to check in on this in case of future problems.

I may not fully grasp the concept of both in use at the same time.

Reboot issue turned out to be an issue while installilng the APs. The uplink port was Eth1 and not Eth0, on top of this we have wired AP profiles, so something in this combination was causing the issues. Moved the uplink to Eth0 and all APs came up.

 

Thanks for the information on HA though!

to add to this old thread for benefit of others, I have seen a situation where both HA and LMS/backup LMS were configured. It caused problems because of the licensing. In the case of AP being unable to reach any controller e.g. due to intermediate uplink outage, it would mark the LMS down and try to connect to the backup LMS. The issue is that with AOS6.x HA licensing, the secondary controller is not normally fully licensed. The legacy backup LMS redundancy attempts to form a primary tunnel to the secondary controller and is rejected due to licensing. AN AP reboot is then required. By removing the backup LMS setting the AP will never attempt to establish a primary tunnel to the secondary controller and will not get confused in the event of uplink loss.

Original Message:
Sent: Sep 15, 2016 11:58 AM
From: mharing
Subject: HA + LMS/Backup LMS Problems

Reboot issue turned out to be an issue while installilng the APs. The uplink port was Eth1 and not Eth0, on top of this we have wired AP profiles, so something in this combination was causing the issues. Moved the uplink to Eth0 and all APs came up.

 

Thanks for the information on HA though!