Name resolution lost when restarting Fritzbox

Help
21

I'm in trouble now. This time that means I cannot resolve any domains at all.

robert@linux-ehou:~> ping 192.168.178.92
PING 192.168.178.92 (192.168.178.92) 56(84) bytes of data.
From 192.168.178.100 icmp_seq=1 Destination Host Unreachable
From 192.168.178.100 icmp_seq=2 Destination Host Unreachable
From 192.168.178.100 icmp_seq=3 Destination Host Unreachable
^C
--- 192.168.178.92 ping statistics ---
4 packets transmitted, 0 received, +3 errors, 100% packet loss, time 3059ms
pipe 4
robert@linux-ehou:~> ping 192.168.178.1
PING 192.168.178.1 (192.168.178.1) 56(84) bytes of data.
64 bytes from 192.168.178.1: icmp_seq=1 ttl=64 time=0.447 ms
64 bytes from 192.168.178.1: icmp_seq=2 ttl=64 time=0.512 ms
^C
--- 192.168.178.1 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1027ms
rtt min/avg/max/mdev = 0.447/0.479/0.512/0.039 ms
robert@linux-ehou:~> nslookup pi.hole
Server: 192.168.178.1
Address: 192.168.178.1#53
** server can't find pi.hole: NXDOMAIN

The Pi doesn't show up on the Fritzbox's local network overview, so I assume it is not connected.

22

Pi-hole would not have an impact on pinging external IP addresses. The issue would be in your gateway (router).

Have you tried restarting the Pi-hole? (might have to physically remove the power)

23

You must have changed something as before, your "linux-ehou" machine was resolving DNS names using Pi-hole 192.168.178.92 :

Now its resolving using your router 192.168.178.1 :

Do you remember what you changed ?
And what is in below file on the "linux-ehou" system:

cat /etc/resolv.conf

And who is doing DHCP when running below one on the "linux-ehou" system ?

sudo dhclient -r; sudo dhclient -v

24

Can you log in to Pi-hole and check network ?

25

Yes, that always helps. The problem is that at the moment it doesn't work reliably.

No, I didn't change any configurations in between these posts. I guess the router shows up as name server, because when the problem occurs, the Pi is disconnected from the network and so the "linux-ehou" "falls back" to the router as a name server.

@linux-ehou:~> cat /etc/resolv.conf
search fritz.box
nameserver 192.168.178.92
nameserver 192.168.178.1

And i get this:

@linux-ehou:~> sudo dhclient -r; sudo dhclient -v
/sbin/dhclient-script: unable to pre-init requested interface enp5s0
/sbin/dhclient-script: unable to pre-init requested interfaces -- see log messages

I will setup the Pi in a more suitable place in my room, so when the problem occurs again, I can connect peripherals and check the network.

26

Need to remove the Fritzbox DNS service (192.168.178.1) from the DHCP client/LAN settings on Fritzbox or ads will still leak through:

Dont forget to renew DHCP lease after on the clients by either disconnecting/reconnecting network or reboot the clients!

27

So far I didn't seem to have any issues with that, but thank you, I will adjust it. So far I had only set it up through Yast, so I wasn't entirely sure what's happening behind the scenes...