dnsblog timeout

maybl8

Seeing this in the postfix log

warning: dnsblog reply timeout 10s for dnsbl.sorbs.net 05/10/2023, 11:25:34 AM warning warning: dnsblog_query: lookup error for DNS query 19.175.73.134.dnsbl.sorbs.net: Host or domain name not found. Name service error for name=19.175.73.134.dnsbl.sorbs.net type=A: Host not found, try again

teissler

Hello maybl8,

this is one of the messages related to https://community.mailcow.email/d/2250-resolver-failed-to-read-from-dns-server-io-timeout/16

Can you verify that you have messages like dockerd * level=warning msg="[resolver] failed to read from DNS server: * i/o timeout" in your logs?

kind regards,
Timo

maybl8

teissler I don’t understand how to find the logs except for when I use the mailcow ui. I tried reading the manual but it doesn’t make sense to me on how to do it. Can you tell me the steps to get the info you want?
Thanks

teissler

@maybl8 what linux distribution do you use? Or do you use some kind of hosted mailcow installation?

On a debian system the messages will occur in /var/log/daemon.log.

maybl8

I am using mailcow dockerized on Arch Linux on my own server.

Did some web searching came up with this. Now I need to figure out what to look for if this is the logs?
journalctl -u docker.service

teissler

ok, you can search all your logs within /var/log/ for related messages with the following command.

grep -ir 'i/o timeout' /var/log/*

You should search for messages like
May 10 07:22:01 mail01 dockerd[1795]: time="2023-05-10T07:22:01.230760757+02:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;38.249.246.80.dnsbl.sorbs.net.\tIN\t A" error="read udp 172.22.1.253:46326->172.22.1.254:53: i/o timeout"

maybl8

The journal command gives me this:
ay 10 22:19:36 mail systemd[1]: Starting Docker Application Container Engine... May 10 22:19:41 mail dockerd[353]: time="2023-05-10T22:19:41.962991756-04:00" level=info msg="Starting up" May 10 22:19:43 mail dockerd[353]: time="2023-05-10T22:19:43.473595974-04:00" level=info msg="[graphdriver] using prior storage driver: overlay2" May 10 22:19:49 mail dockerd[353]: time="2023-05-10T22:19:49.877398252-04:00" level=info msg="Loading containers: start." May 10 22:19:50 mail dockerd[353]: time="2023-05-10T22:19:50.941223572-04:00" level=error msg="Could not add route to IPv6 network fd4d:6169:6c63:6f77::1/64 via device br-mailcow:> May 10 22:19:51 mail dockerd[353]: time="2023-05-10T22:19:51.252216166-04:00" level=info msg="Default bridge (docker0) is assigned with an IP address 172.17.0.0/16. Daemon option > May 10 22:20:08 mail dockerd[353]: time="2023-05-10T22:20:08.346922209-04:00" level=info msg="ignoring event" container=d26efdc9f3d4a57bcbf51b3e8d083f0d8175f76b0c6c2a3ff6c9133a259> May 10 22:20:11 mail dockerd[353]: time="2023-05-10T22:20:11.264270050-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;postfix.\tIN\t> May 10 22:20:11 mail dockerd[353]: time="2023-05-10T22:20:11.264270026-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;postfix.\tIN\t> May 10 22:20:13 mail dockerd[353]: time="2023-05-10T22:20:13.071995824-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;current.cvd.cl> May 10 22:20:18 mail dockerd[353]: time="2023-05-10T22:20:18.570798426-04:00" level=info msg="Loading containers: done." May 10 22:20:19 mail dockerd[353]: time="2023-05-10T22:20:19.562676040-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;current.cvd.cl> May 10 22:20:20 mail dockerd[353]: time="2023-05-10T22:20:20.125627629-04:00" level=warning msg="Not using native diff for overlay2, this may cause degraded performance for buildi> May 10 22:20:20 mail dockerd[353]: time="2023-05-10T22:20:20.125816432-04:00" level=info msg="Docker daemon" commit=9dbdbd4b6d graphdriver=overlay2 version=23.0.6 May 10 22:20:21 mail dockerd[353]: time="2023-05-10T22:20:21.432383846-04:00" level=info msg="Daemon has completed initialization" May 10 22:20:21 mail dockerd[353]: time="2023-05-10T22:20:21.441879407-04:00" level=info msg="ignoring event" container=d26efdc9f3d4a57bcbf51b3e8d083f0d8175f76b0c6c2a3ff6c9133a259> May 10 22:20:22 mail dockerd[353]: time="2023-05-10T22:20:22.303748052-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;database.clama> May 10 22:20:22 mail dockerd[353]: time="2023-05-10T22:20:22.303750055-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;database.clama>

teissler

You’re loglines seams to be truncated.

You can also use journalctl -u docker.service | grep -i 'i/o timeout' to get only relevant messages.

maybl8

Here is some of them with the last command you gave me:
May 11 12:16:19 mail dockerd[353]: time="2023-05-11T12:16:19.870944020-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;134.78.72.149.list.dnswl.org.\tIN\t A" error="read udp 172.22.1.5:60349->172.22.1.254:53: i/o timeout" May 11 12:16:20 mail dockerd[353]: time="2023-05-11T12:16:20.872083651-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;134.78.72.149.list.dnswl.org.\tIN\t A" error="read udp 172.22.1.5:51213->172.22.1.254:53: i/o timeout" May 11 12:16:21 mail dockerd[353]: time="2023-05-11T12:16:21.976853687-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;134.78.72.149.ix.dnsbl.manitu.net.\tIN\t A" error="read udp 172.22.1.5:53906->172.22.1.254:53: i/o timeout" May 11 12:16:22 mail dockerd[353]: time="2023-05-11T12:16:22.977512814-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;134.78.72.149.ix.dnsbl.manitu.net.\tIN\t A" error="read udp 172.22.1.5:42447->172.22.1.254:53: i/o timeout" May 11 12:18:56 mail dockerd[353]: time="2023-05-11T12:18:56.374694998-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;9.229.251.178.ix.dnsbl.manitu.net.\tIN\t A" error="read udp 172.22.1.253:34063->172.22.1.254:53: i/o timeout" May 11 12:18:56 mail dockerd[353]: time="2023-05-11T12:18:56.432912430-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;9.229.251.178.dnsbl.sorbs.net.\tIN\t A" error="read udp 172.22.1.253:41120->172.22.1.254:53: i/o timeout" May 11 12:18:56 mail dockerd[353]: time="2023-05-11T12:18:56.447990010-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;9.229.251.178.bl.suomispam.net.\tIN\t A" error="read udp 172.22.1.253:49241->172.22.1.254:53: i/o timeout" May 11 12:18:59 mail dockerd[353]: time="2023-05-11T12:18:59.084521128-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;mail.servercow.de.\tIN\t A" error="read udp 172.22.1.253:40930->172.22.1.254:53: i/o timeout" May 11 12:19:05 mail dockerd[353]: time="2023-05-11T12:19:05.644592454-04:00" level=warning msg="[resolver] failed to read from DNS server: 172.22.1.254:53, query: ;mailcow.email.dwl.dnswl.org.\tIN\t A" error="read udp 172.22.1.5:49066->172.22.1.254:53: i/o timeout"

teissler

so it’s definetly the same case. I your normal DNS resolution works, you don’t have a problem at all :-)

maybl8

So those are expected errors?
Good to know

teissler

No, these are warnings and they just show issues which other server administrators have.
Read the answer in the thread i linked in my first answer. I described it in detail there.

maybl8

Thanks I will.

While I have you can you look at my other post about moving my mail from my iRedmail?

teissler

Sorry, but i think you are going a unneccessary hard way. i think you should invest in a second VM and migrate then with imapsync.