Port 53 bound after installation of May update?

Help and Support Raspberry Pi
1

Hi all,

after installation of the latest update 2023.05-1 (PI 3 version) my PI-HOLE failed to start. pi-hole is installed as a docker image and worked perfectly until I updated osmc to the latest version.
I have the suspicion that the update changed something around the usage of port 53. Could this be the case?

I just run the following command:

sudo lsof -i :53

Output:

COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
connmand 341 root 11u IPv4 10661 0t0 UDP osmc:domain
connmand 341 root 12u IPv6 10665 0t0 UDP osmc:domain
connmand 341 root 13u IPv4 10669 0t0 TCP osmc:domain (LISTEN)
connmand 341 root 14u IPv6 10673 0t0 TCP osmc:domain (LISTEN)
connmand 341 root 17u IPv4 9648 0t0 UDP osmc:46952->dns.google:domain
connmand 341 root 18u IPv4 9650 0t0 UDP osmc:55436->dns.google:domain
connmand 341 root 19u IPv4 13338 0t0 UDP osmc:56423->dns.google:domain

Unfortunately I do not know how this looked before the update. Could it be the case that “osmc:domain” is bound to the port and therefore my pi-hole does not start anymore? Can this be deactivated to use port 53 for pi-hole?

Thanks a lot.
Tombar

2

fixed it, I hope I did it right. Until now it seems to work.

sudo nano /usr/bin/start-network

changed:

else
if echo “$dnsproxy” | grep -iqw no; then
exec /usr/sbin/connmand -n --nodnsproxy --config=/etc/connman.conf
else
exec /usr/sbin/connmand -n --config=/etc/connman.conf
fi
fi

to:

else
if echo “$dnsproxy” | grep -iqw no; then
exec /usr/sbin/connmand -n --nodnsproxy --config=/etc/connman.conf
else
exec /usr/sbin/connmand -n --config=/etc/connman.conf --nodnsproxy
fi
fi

within the else if added “–nodnsproxy”.

3

You should change this properly in /etc/osmc preferences, otherwise it will be overwritten by updates.

4

Hi Sam,

ok, can you please let me know which file exactly I have to modify and what to add.

Thanks.

5

It’s under /etc/connman.prefs

6

thanks a lot Sam. Yes this is a better setting than the one I initially changed and it works perfectly for my use case.

7

Hello,

To support people who might be facing the same.
I’ve faced this issue in the past, and editing the /etc/connman.prefs did the trick.
After Dec/23 update, connman was binding the 53 port again (even though it had dnsproxy=no in the file above).

After searching for additional config files, I’ve also had to change the file /etc/osmc/prefs.d/connman. After changing this second file to dnsproxy=no, the 53 port is not bound at boot and Pihole is back online.

1 Like
8

Sorry – I changed this to match /etc/osmc-prefs.d nomenclature recently.
I didn’t think many people were using this option so didn’t widely document it

Sam

1 Like
9

Hi Sam,
Yes, please ensure our pihole play nicely with OSMC. I have several Pi’s in the house and one dedicated to pihole and OSMC as it’s not the Pi that gets a lot of attention as the others do. The pihole has its duty to protect the house.

Thank you!