On one of my pfSense boxes I've seen Unbound segfault a couple of times. Since pfSense doesn't seem to monitor Unbound, it will not automatically restart and will thus require manual intervention. pfSense is running in a VM on a box with ECC memory, so I highly doubt this is a hardware issue.
Example log lines are:
- kernel: pid 8272 (unbound), uid 59: exited on signal 11
- kernel: pid 22346 (unbound), uid 59: exited on signal 11
- I think I've also seen a signal 10 once
Affected versions are all 2.2.x releases so far.
If there is a way to collect more information, I'd be happy to do so.
Related forum post: https://forum.pfsense.org/index.php?topic=94045