Warning: Cannot get exclusive lock for /etc/pihole/pihole.toml: Bad file descriptor

alomeli · April 20, 2025, 4:35pm

Hi All,

Im getting this constant warning that Im unable to know why this warning is here.

"Cannot get exclusive lock for /etc/pihole/pihole.toml: Bad file descriptor"

Using docker image 2025.04.0 version.

Everything is running smooth, Im able to view Admin UI, update the file from UI and works great. but the warning still there.

Thanks!

alomeli · April 21, 2025, 1:15am

Looks like this is related

github.com/pi-hole/docker-pi-hole

Fresh deployment = Cannot open config file /etc/pihole/pihole.toml in exclusive mode (r): Bad file descriptor

opened 08:32PM - 19 Feb 25 UTC

closed 10:36AM - 01 Apr 25 UTC

virtualex-itv

stale

This is a: Bug ## Details spinning up a new instance of pihole v6 today in …docker and using the newer env vars. however, when i spin up the container I am seeing the following error in the logs: ``` Cannot open config file /etc/pihole/pihole.toml in exclusive mode (r): Bad file descriptor ``` therefore, none of the settings i am trying to configure are getting applied. **Note: This seems to happen only if/when using a persistent volume on an external device (NFS in my case).** ## Related Issues - [x] I have searched this repository/Pi-hole forums for existing issues and pull requests that look similar ## How to reproduce the issue 1. Environment data * Operating System: **Ubuntu** * VMware VMs & RasPi 4B: * Kernel Architecture:x86 & Arm 64bit * Docker Install Info and version: - Software source: official docker-ce - Supplimentary Software: portainer * Hardware architecture: x86 & ARMv7 2. docker-compose.yml contents, docker run shell command, or paste a screenshot of any UI based configuration of containers here ``` services: pihole: image: pihole/pihole:latest container_name: pihole restart: unless-stopped security_opt: - no-new-privileges:false hostname: pi.hole environment: # recommended - TZ=${TZ} - FTLCONF_webserver_api_password=${SECRET} # optional - FTLCONF_dns_upstreams=1.1.1.1;9.9.9.9 - FTLCONF_dns_dnssec=true - FTLCONF_dns_bogusPriv=true - FTLCONF_dns_domainNeeded=true - FTLCONF_webserver_interface_theme=auto # advanced - FTLCONF_dns_specialDomains_iCloudPrivateRelay=false volumes: - ${DOCKER_DIR}/appdata/pihole/pihole:/etc/pihole - ${DOCKER_DIR}/appdata/pihole/dnsmasq.d:/etc/dnsmasq.d networks: proxy: ports: - 53:53/tcp - 53:53/udp - 1080:80/tcp - 1443:443/tcp dns: - 127.0.0.1 - 1.1.1.1 networks: proxy: external: true ``` ## These common fixes didn't work for my issue - [x] I have tried removing/destroying my container, and re-creating a new container - [x] I have tried fresh volume data by backing up and moving/removing the old volume data - [x] I have tried running the stock `docker run` example(s) in the readme (removing any customizations I added) - [x] I have tried a newer or older version of Docker Pi-hole (depending what version the issue started in for me) - [x] I have tried running without my volume data mounts to eliminate volumes as the cause If the above debugging / fixes revealed any new information note it here. Add any other debugging steps you've taken or theories on root cause that may help.