Pi-hole beta occasionally gets "stuck" and stops responding to DNS requests

[neeez]

Please follow the below template, it will help us to help you!

Pi-hole beta occasionally gets "stuck" and stops responding to DNS requests (that should be responded to). After a few seconds or minutes, things start working again without a need for further intervention.

The machine is a beefy quad core xeon running Ubuntu directly, so I feel like if this runs on a Pi, it should run great on this machine.

Expected Behaviour:

No freezes or stuck DNS queries.

Actual Behaviour:

Random and occasional "stuck" DNS. pihole -t shows nothing interesting while it is stuck, and continues on after it gets unstuck.

Debug Token:

Bad tokens (most confident of the first one) taken while stuck:

y64sjicevo
3m94uezu92

Good token (no stuck):

fyjwj8u14e

[Mcat12]

Check /var/log/pihole.log and /var/log/pihole-FTL.log when it's stuck and not stuck. Also, are you able to SSH in while it's stuck?

[neeez]

I think /var/log/pihole.log is just the output of pihole -t, right? That also appears stuck when the DNS is stuck.

I can SSH no problem (can run commands remotely, etc) while it is stuck.

I can tail /var/log/pihole-FTL.log

but here is the current contents of that file:

cat /var/log/pihole-FTL.log
[2018-07-17 07:10:00.590] Notice: Increasing overTime struct size from 200 to 300 (2.74 MB)
[2018-07-17 12:53:24.708] Notice: Increasing queries struct size from 40000 to 50000 (3.39 MB)
[2018-07-17 19:41:08.259] Notice: Increasing queries struct size from 50000 to 60000 (4.04 MB)
[2018-07-17 21:47:28.887] Notice: Increasing domains struct size from 3000 to 4000 (4.08 MB)

[Mcat12]

When it is stuck, does the web interface work correctly?

[neeez]

No, it does not.

[Mcat12]

Try the FTL debugging instructions: Debugging FTLDNS - Pi-hole documentation