Hi,
This may be a Bind issue but, I can't seem to find any explanation for it so asking here in case someone else has encountered the issue before.
I've moved a domain between 2 virtualmin servers, one running Ubuntu 14.04 (the slave) and the second running 16.06 (the master). Both servers are running virtualmin 6.01-2 and using the Cluster Slave Servers feature. Am in the process of migrating to the newer server and have successfully moved a dozen or so domains already. With the domain in question though, the slave is loading an old version of the zone from somewhere. I can't for the life of me figure out where though!
No errors on the master server and, if I query it with dig I get the correct, expected results. However, if I do an axfr query, I get an old version of the zone with the IP's pointing to the old server. Serial number for my current zone, being served for queries, is higher than the older zone serial number and, I can't find anywhere on either server where this older zone version might be coming from. I've deleted from the slave and recreated several times as well as turning dns off and on in virtualmin to delete/recreate the zone on the slave. No errors in my zone file or bind config that are reported on either master or slave.
Any suggestions? I've been using Virtualmin for almost a decade and have never encountered an issue like this before!
Found the problem. A second instance of Bind was running and serving up the old zone file on the internal IP while the correct info was being served on the public IP. Not quite sure how yet but, killing the second instance made the correct zone file version get transferred to the secondary.