Failover DNS time to return to Primary

[torresfrank1]

I have 2 instances of 3CX. Whenever the main server goes down, the second server comes in without issues. However, whenever the first server comes back on, I have to go thru a process to get it to update the DNS. Both are on-prem installations with different Public IP Addresses. I go to secondary and select passive on the failover selector. Still, I am rebooting both servers, and takes longer than 30 minutes. Today it took 2 hours. I am using ENT licensing. Any help on this will be appreciated.

 

[VasilisV_3CX]

Hi @torresfrank1,

When you say it took 2 hours, do you mean that it takes 2 hours for the FQDN to resolve back to the primary's public IP again? If yes, how are you checking this? I'd suggest checking from a different PC (since there may be a caching issue) and you may want to test on an external site like: https://toolbox.googleapps.com/apps/dig/

Provided you're using a 3CX FQDN, with an ENT license your TTL should be 5 minutes which I'm sure you are aware of.

This could also be caused by your firewall or even by your ISP.