After upgrading my home firewall/IDS to OPNsense 18.7.9, I noticed that the unbound service stops randomly at least once a day. Worst is, it may happen more than once a day! Because  unbound is my DNS resolver, previous connections are not lost. I can only find that the service is stopped when connecting to new website.

I could use the Monit service to automatically restart the unbound service but I don’t like the feeling that unbound should crash and be restarted, right?

I did not find any error on the logs why unbound is crashing so the best thing to do is to revert to previous version of OPNsense. However, only the unbound service has an issue. I want to use the latest OPNsense and other packages except unbound. Luckily, OPNsense has a tool to revert to previous version of a particular package.

Login to your OPNsense via SSH and execute the following:

opnsense-revert -r 18.7.4 unbound

This will revert unbound to version 1.7.3.

So far, unbound has not stopped working for 3 days now.

Update: unbound 1.8.1 is also stable. Tried 1.8.2 and 1.8.3 but they are both unstable.

 opnsense-revert -r 18.7.6 unbound