Sporadic DNS issues, cryptic error in logs.

[zaitz]

Hello!

I have started getting DNS_PROBE_FINISHED_NXDOMAIN errors randomly. When i first klick on a link from time to time I will get a DNS timeout, but on the second klick everything works as expected. Same behavior on different machines, all have DNS pointed to pfsense.

When i look at DNS resolver logs i have the same error every second just rolling and rolling. When I restart DNS Resolver the error disappears for some amount of time and the reappears.

The error is:
unbound 83772 [83772:3] error: in comm_point_tcp_handle_read buffer_remaining is not > 0 as expected, continuing with (harmless) 0 length recv

Any idea what this could be? I have Suricata installed, with monitoring but not blocking. Also OpenVPN, not much else.

Any help appreciated.

[The Party of Hell No]

@zaitz
https://forum.netgate.com/topic/188303/unbound-crashing-randomly-after-24-03-upgrade

Not specifically your problem, however in other posts this was suggested as a way to stop this error.

Most probable cause : uncheck this one:

[SteveITS]

@zaitz Here's a thread with that message, no solution yet though:
https://forum.netgate.com/topic/187510/dns_probe_finished_nxdomain-sporadically-for-anywhere-from-30secs-to-10min-works-flawlessly-at-all-other-times

If you have Resolver set to forward, uncheck DNSSEC.

[zaitz]

Unluckily these are not it, as I don't have eather "DNSSEC" nor "Register DHCP" activated.

[The Party of Hell No]

@zaitz
DNS_PROBE_FINISHED_NXDOMAIN - search the database, yours is not the first error like this.

Maybe also, if you have a pre-update config file... might restore it and reboot - make a current config file before proceeding to get back to current if it does not rid the error code.

[The Party of Hell No]

@The-Party-of-Hell-No
Another post:

https://forum.netgate.com/topic/187510/dns_probe_finished_nxdomain-sporadically-for-anywhere-from-30secs-to-10min-works-flawlessly-at-all-other-times/31