Invalid configuration dnsmasq: syntax check OK.

General Beta 6.0
1

I have problems with my PiHole v6. I try to start the DHCP server (after moving from an RPi to Proxmox) and always get the message: “ Invalid configuration
dnsmasq: syntax check OK.”. also importing the configuration via teleporter gave the same error.
I have taken over the pihole.toml from the old Pihole. the DHCP starts without problems on the old Pi, but not on the new Proxmox Pihole. Of course I deactivated the old Pi beforehand.

I see the following messages in the ftl.log:

“2025-01-03 17:55:34.688 ERROR Error NTP client: Failed to adjust time during NTP sync: Insufficient permissions
2025-01-03 17:56:22.732 ERROR Cannot wait for dnsmasq test: No child process
2025-01-03 17:56:22.732 ERROR dnsmasq test failed with signal 4
2025-01-03 17:56:22.733 WARNING New dnsmasq configuration is not valid (dnsmasq: syntax check OK.), config remains unchanged
2025-01-03 17:56:22.733 WARNING API: Invalid configuration (dnsmasq: syntax check OK.)”

Translated with DeepL.com (free version)```
2

This might be a bug that has been fixed 12 hours ago.

https://github.com/pi-hole/FTL/pull/2151

Please run pihole -up and see if the issue persists.

3

` [i] Pi-hole Core: up to date
[i] Web Interface: up to date
[i] FTL: up to date

[✓] Everything is up to date!`

the error persits

4

Please upload a debug log and post just the token URL that is generated after the log is uploaded by running the following command from the Pi-hole host terminal:

pihole -d
5

Has there been any development with this issue? Seeing the same problem on my end, also running Pi-hole in an LXC on Proxmox. Log output is similar when trying to start the DHCP server (verifying all other fields are correct):

2025-02-20 14:27:56.187 UTC [14825/T15128] ERROR: Cannot wait for dnsmasq test: No child process
2025-02-20 14:27:56.187 UTC [14825/T15128] ERROR: dnsmasq test failed with signal 2
2025-02-20 14:27:56.187 UTC [14825/T15128] WARNING: New dnsmasq configuration is not valid (dnsmasq: syntax check OK.), config remains unchanged
2025-02-20 14:27:56.187 UTC [14825/T15128] WARNING: API: Invalid configuration (dnsmasq: syntax check OK.)

6

Do you have any additional config files in /etc/dnsmasq.d/?

8

It is not really the same, previously it was signal 4, you are seeing signal 2. Can you reproduce it?

edit @mkmeyer34 Please run

sudo pihole checkout ftl fix/echild

and see if this fixes the problem for you.

https://github.com/pi-hole/FTL/pull/2231

9

There were no configuration files in this folder, before or after attempting to turn on DHCP.

10

I ended up moving the Pi-hole installation onto a VM instead of an LXC. All the issues resolved themselves (including NTP issues). When I get a moment I'd be happy to test the changes, I'd prefer to containerize if possible but I can afford the additional resource use at the moment.

11

You can also use the official docker container for most simple containerization: GitHub - pi-hole/docker-pi-hole: Pi-hole in a docker container

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