3 weeks ago, JAMF helped us add a 2nd JSS server and create a cluster. We don't have a load balancer so we used DNS round-robin (Win 2008r2 DNS) for a poor-mans load balancing.
We had 2 identical DNS A records pointing to 2 different IPs (2 different servers). That was the internal DNS. External DNS was just 1 A record pointing to the internal Master server (the original JSS). However, we have had JSS since 8.5 so we had originally used a different name way back then for the 1st JSS server. That name is still being used as the JSS URL. At the time JAMF said we could just CNAME that name to the new JSS server we installed then (now master JSS server) and not have to re-enroll devices. After adding the cluster, DNS looked like this:
Internal
IP1, IP2 > A record>CNAME
External
IP1>A record>CNAME
Kinda worked and kinda didn't. Logging into the JSS was fine, that round-robin'd fine. But the devices had problems. Self-Service on devices would, sometimes, say "Server cannot be contacted" The fix was to just turn off/on wifi. However the issue would return after a few days. Very possibly after the devices went home overnight. We removed the A record for the 2nd JSS and devices are fine.
Should we just bite-the-bullet and get a load balancer?
What about getting rid of the CNAME from the original JSS that no longer is here?
Should we spin up a 3rd JSS server, name it the original JSS (the CNAME) and make it the new Master?
Any other recommendations?
**EDIT Clustering and DNS !