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Date: 2023/09/05

Author: Tristan Ancelet

Blog Issue


Looks like my master DNS server was down for the last 3 days (didn't know until the teacher mentioned it). Had to end up taking a look at my provider and it looks like my master DNS server had crashed at some point. After restarting it I got everything started up and it seems to have come back up.

I had a backup DNS server as well, but after looking into the VM (that was still running), it turns out that I never whitelisted the DNS port (53/udp) on it. So it's entire life has been failure (as it's been the backup for several months). My thought is that I DID whitelist it but not perminately. So after a reboot it cleared the config and DNS traffic wasn't whitelisted it anymore.

Here is the commands it did to whitelist DNS (running firewalld as a device side firewall)

firewall-cmd --perm --zone=public --add-service=dns
firewall-cmd --reload

After checking that DNS was resolving with dig, I was able to visit my site with no more issues.