Pi-hole in container blocking valid sites

Software SW tweaks
1

After update to newest version v6 of pi-hole in Debian container it started to block valid sites after about 2-3 hours of running (e.g. forum.turris.cz etc). Had to disable blocking, stop container and revert DNS back from Pihole to CZ.NIC.

Will investigate later. Any thoughts?

2

updated as well. no problems here

3

It’s peculiar. After update to latest versions of Pi-hole parts (6.0.x) and restarting it, it started to block valid sites again. I don’t understand it - before Pi-hole version 6 there were no problems.

4

The version update is likely just a coincidence. Pi-Hole blocks sites that are in its block lists. Have you queried the lists to see which one has the blocked sites on?

1 Like
5

I searched Pi-hole log for information about blocked 'cz" domains, and, I have to admit that I don’t understand why I was not able to open eg. Turris forum, or Nova News… see details below.

Pi-hole status

root@LXCNAME:~# pihole status
[✓] FTL is listening on port 53
[✓] UDP (IPv4)
[✓] TCP (IPv4)
[✓] UDP (IPv6)
[✓] TCP (IPv6)

[✓] Pi-hole blocking is enabled

Query Pi-hole for blocked 'cz' domains

root@LXCNAME:/# pihole -q --partial cz
Found 0 domains partially matching ‘cz’.

Found 1 adlists partially matching ‘cz’.

Part of log with dnsmasq replies for 'cz' domains

root@LXCNAME:/# cat /var/log/pihole/pihole.log | grep .cz | grep -v forwarded | grep -v query | head -n 100
Feb 27 08:26:55 dnsmasq[178]: reply seznam.cz is
Feb 27 08:26:55 dnsmasq[178]: reply seznam.cz is
Feb 27 08:26:55 dnsmasq[178]: reply seznam.cz is
Feb 27 08:26:55 dnsmasq[178]: reply seznam.cz is
Feb 27 08:26:55 dnsmasq[178]: reply seznam.cz is
Feb 27 08:26:55 dnsmasq[178]: reply slovnik.seznam.cz is 77.75.78.131
Feb 27 08:26:55 dnsmasq[178]: reply slovnik.seznam.cz is 77.75.76.131
Feb 27 08:26:55 dnsmasq[178]: reply slovnik.seznam.cz is
Feb 27 08:26:55 dnsmasq[178]: reply szn.cz is
Feb 27 08:26:55 dnsmasq[178]: reply szn.cz is
Feb 27 08:26:55 dnsmasq[178]: reply iva.seznam.cz is NODATA
Feb 27 08:26:55 dnsmasq[178]: reply szn.cz is
Feb 27 08:26:55 dnsmasq[178]: reply szn.cz is
Feb 27 08:26:55 dnsmasq[178]: reply szn.cz is
Feb 27 08:26:55 dnsmasq[178]: reply bcr.iva.seznam.cz is 77.75.79.3
Feb 27 08:26:55 dnsmasq[178]: reply bcr.iva.seznam.cz is
Feb 27 08:26:55 dnsmasq[178]: reply login.szn.cz is 77.75.78.104
Feb 27 08:26:55 dnsmasq[178]: reply login.szn.cz is
Feb 27 08:26:56 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:26:56 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
Feb 27 08:26:56 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:26:56 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
Feb 27 08:26:56 dnsmasq[178]: reply pszn.cz is
Feb 27 08:26:56 dnsmasq[178]: reply pszn.cz is
Feb 27 08:26:56 dnsmasq[178]: reply pszn.cz is
Feb 27 08:26:56 dnsmasq[178]: reply pszn.cz is
Feb 27 08:26:56 dnsmasq[178]: reply pszn.cz is
Feb 27 08:26:56 dnsmasq[178]: reply sentry.pszn.cz is 77.75.78.244
Feb 27 08:26:56 dnsmasq[178]: reply sentry.pszn.cz is
Feb 27 08:26:56 dnsmasq[178]: reply cmp.seznam.cz is 77.75.76.214
Feb 27 08:26:56 dnsmasq[178]: reply cmp.seznam.cz is
Feb 27 08:26:56 dnsmasq[178]: reply login.seznam.cz is
Feb 27 08:26:56 dnsmasq[178]: reply login.szn.cz is 77.75.78.104
Feb 27 08:26:56 dnsmasq[178]: reply login.szn.cz is
Feb 27 08:26:56 dnsmasq[178]: reply h.seznam.cz is 77.75.76.30
Feb 27 08:26:56 dnsmasq[178]: reply h.seznam.cz is 77.75.78.30
Feb 27 08:26:56 dnsmasq[178]: reply h.seznam.cz is
Feb 27 08:27:08 dnsmasq[178]: reply teplarny.cz is NODATA
Feb 27 08:27:08 dnsmasq[178]: reply www.teplarny.cz is 62.109.150.243
Feb 27 08:27:09 dnsmasq[178]: reply google.cz is NODATA
Feb 27 08:27:09 dnsmasq[178]: reply www.google.cz is 142.251.36.67
Feb 27 08:27:48 dnsmasq[178]: reply repo.turris.cz is 2001:1488:ac15:ff80::84
Feb 27 08:27:48 dnsmasq[178]: reply repo.turris.cz is
Feb 27 08:27:50 dnsmasq[178]: reply www.nic.cz is 2001:1488:0:3::2
Feb 27 08:27:50 dnsmasq[178]: reply www.nic.cz is
Feb 27 08:27:50 dnsmasq[178]: reply rhybar.cz is
Feb 27 08:27:50 dnsmasq[178]: reply rhybar.cz is
Feb 27 08:31:08 dnsmasq[178]: reply autozive.cz is NODATA
Feb 27 08:31:08 dnsmasq[178]: reply www.autozive.cz is 104.21.112.1
Feb 27 08:31:08 dnsmasq[178]: reply www.autozive.cz is 104.21.16.1
Feb 27 08:31:08 dnsmasq[178]: reply www.autozive.cz is 104.21.32.1
Feb 27 08:31:08 dnsmasq[178]: reply www.autozive.cz is 104.21.48.1
Feb 27 08:31:08 dnsmasq[178]: reply www.autozive.cz is 104.21.64.1
Feb 27 08:31:08 dnsmasq[178]: reply www.autozive.cz is 104.21.80.1
Feb 27 08:31:08 dnsmasq[178]: reply www.autozive.cz is 104.21.96.1
Feb 27 08:31:08 dnsmasq[178]: reply imedia.cz is
Feb 27 08:31:08 dnsmasq[178]: reply imedia.cz is
Feb 27 08:31:08 dnsmasq[178]: reply imedia.cz is
Feb 27 08:31:08 dnsmasq[178]: reply imedia.cz is
Feb 27 08:31:08 dnsmasq[178]: reply imedia.cz is
Feb 27 08:31:08 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:31:08 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
Feb 27 08:31:08 dnsmasq[178]: reply 1gr.cz is 185.17.117.38
Feb 27 08:31:08 dnsmasq[178]: reply 1gr.cz is
Feb 27 08:31:08 dnsmasq[178]: reply 1gr.cz is
Feb 27 08:31:08 dnsmasq[178]: reply 1gr.cz is
Feb 27 08:31:08 dnsmasq[178]: reply 1gr.cz is
Feb 27 08:31:08 dnsmasq[178]: reply 1gr.cz is
Feb 27 08:31:08 dnsmasq[178]: reply 1gr.cz is
Feb 27 08:31:08 dnsmasq[178]: reply performax.cz is NODATA
Feb 27 08:31:08 dnsmasq[178]: reply cdn.performax.cz is 109.123.210.81
Feb 27 08:31:08 dnsmasq[178]: reply cdn.performax.cz is 109.123.210.83
Feb 27 08:31:08 dnsmasq[178]: reply cdn.performax.cz is 109.123.221.171
Feb 27 08:31:08 dnsmasq[178]: reply cdn.performax.cz is
Feb 27 08:31:08 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:31:08 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
Feb 27 08:31:08 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:31:08 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
Feb 27 08:31:09 dnsmasq[178]: reply sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: reply sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: reply sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: reply sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: reply sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: reply d21-a.sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: reply lb.sdn.cz is 77.75.77.195
Feb 27 08:31:09 dnsmasq[178]: reply lb.sdn.cz is 77.75.79.195
Feb 27 08:31:09 dnsmasq[178]: reply lb.sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: reply lb.sdn.cz is 77.75.79.195
Feb 27 08:31:09 dnsmasq[178]: reply lb.sdn.cz is 77.75.77.195
Feb 27 08:31:09 dnsmasq[178]: reply lb.sdn.cz is
Feb 27 08:31:09 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:31:09 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
Feb 27 08:31:09 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:31:09 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
Feb 27 08:31:09 dnsmasq[178]: reply seznam.cz is
Feb 27 08:31:09 dnsmasq[178]: reply seznam.cz is
Feb 27 08:31:09 dnsmasq[178]: reply seznam.cz is
Feb 27 08:31:09 dnsmasq[178]: reply pocitadlolibise.seznam.cz is 77.75.78.20
Feb 27 08:31:09 dnsmasq[178]: reply pocitadlolibise.seznam.cz is 77.75.76.20
Feb 27 08:31:09 dnsmasq[178]: reply pocitadlolibise.seznam.cz is
root@LXCNAME:/#

Log after trying to open Turris forum

root@LXCNAME:/# cat /var/log/pihole/pihole.log | grep forum.turris.cz | head -n 100
Feb 27 08:50:00 dnsmasq[178]: query[A] forum.turris.cz from 192.168.1.1
Feb 27 08:50:00 dnsmasq[178]: forwarded forum.turris.cz to 208.67.222.222
Feb 27 08:50:00 dnsmasq[178]: reply forum.turris.cz is

Log after trying to open Nova news

root@LXCNAME:/# cat /var/log/pihole/pihole.log | grep tn.nova.cz | head -n 100
Feb 27 08:43:08 dnsmasq[178]: query[A] tn.nova.cz from 192.168.1.1
Feb 27 08:43:08 dnsmasq[178]: forwarded tn.nova.cz to 208.67.222.222
Feb 27 08:43:08 dnsmasq[178]: reply tn.nova.cz is 172.64.150.65
Feb 27 08:43:08 dnsmasq[178]: reply tn.nova.cz is 104.18.37.191
Feb 27 08:43:08 dnsmasq[178]: reply tn.nova.cz is
Feb 27 08:45:08 dnsmasq[178]: query[A] tn.nova.cz from 192.168.1.1
Feb 27 08:45:08 dnsmasq[178]: forwarded tn.nova.cz to 208.67.222.222
Feb 27 08:45:08 dnsmasq[178]: reply tn.nova.cz is 172.64.150.65
Feb 27 08:45:08 dnsmasq[178]: reply tn.nova.cz is 104.18.37.191
Feb 27 08:45:08 dnsmasq[178]: reply tn.nova.cz is

Partial log with blocked 'cz' domains

root@LXCNAME:/# cat /var/log/pihole/pihole.log | grep .cz | grep blocked | head -n 100
Feb 27 08:26:56 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:26:56 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
repeated N times
Feb 27 08:31:09 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:31:09 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
repeated N times
Feb 27 08:31:09 dnsmasq[178]: gravity blocked toplist.cz is 0.0.0.0
Feb 27 08:31:09 dnsmasq[178]: gravity blocked toplist.cz is NODATA
repeated N times
Feb 27 08:31:19 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:31:19 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
repeated N times
Feb 27 08:32:05 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:32:05 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
repeated N times
Feb 27 08:32:06 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:32:06 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
repeated N times
Feb 27 08:32:06 dnsmasq[178]: gravity blocked toplist.cz is 0.0.0.0
Feb 27 08:32:06 dnsmasq[178]: gravity blocked toplist.cz is NODATA
repeated N times
Feb 27 08:32:08 dnsmasq[178]: gravity blocked a.denik.cz is 0.0.0.0
Feb 27 08:32:08 dnsmasq[178]: gravity blocked a.centrum.cz is 0.0.0.0
Feb 27 08:32:08 dnsmasq[178]: gravity blocked a.centrum.cz is NODATA
repeated N times
Feb 27 08:32:28 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:32:28 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
Feb 27 08:33:19 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:33:19 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
repeated N times
Feb 27 08:33:56 dnsmasq[178]: gravity blocked ssp.imedia.cz is 0.0.0.0
Feb 27 08:33:56 dnsmasq[178]: gravity blocked ssp.imedia.cz is NODATA
repeated N times
Feb 27 08:43:01 dnsmasq[178]: gravity blocked a.denik.cz is 0.0.0.0
Feb 27 08:43:08 dnsmasq[178]: gravity blocked ssp.seznam.cz is 0.0.0.0
Feb 27 08:43:08 dnsmasq[178]: gravity blocked ssp.seznam.cz is NODATA
repeated N times
root@LXCNAME:/#

Had to disable Pi-hole again.