Pi-hole DHCP Server “Falls Asleep” After Period of Inactivity

Help
1

Hello,

I’ve noticed a recurring issue with the Pi-hole DHCP server: after a period of network inactivity or low DHCP traffic, the DHCP service appears to “fall asleep” and stops responding to new DHCP requests from devices joining the network. This results in devices being unable to obtain an IP address until the Pi-hole service is restarted or some kind of “keepalive” traffic is generated.

Details:

  • Pi-hole version: Core version is v6.1.2 (Latest: v6.1.2); Web version is v6.2.1 (Latest: v6.2.1); FTL version is v6.2.3 (Latest: v6.2.3)
  • Hardware: Orange Pi 3B
  • OS: Armbian Linux 6.1.115-vendor-rk35xx
  • Network setup: Pi-hole is the only DHCP server on the network

What I’ve tried:

  • Checked Pi-hole and system logs for errors (none found)
  • Ensured no other DHCP servers are present
  • Attempted to create a cron job to periodically generate DHCP or DNS traffic as a workaround, but this did not resolve the issue, even temporarily

Request:
Is this a known bug? Are there any official fixes or recommended configurations to prevent the Pi-hole DHCP server from becoming unresponsive after periods of inactivity? Any help or suggestions would be greatly appreciated.

Thank you!

2

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

or if you run your Pi-hole as a Docker container:

docker exec -it <pihole-container-name-or-id> pihole -d

where you substitute <pihole-container-name-or-id> as required.

And to take a closer look at the time of an observed DHCP outage, please create a dhcp.log excerpt containing DHCP log lines specifically:

sudo grep -n "Jul 11 <hh>.*dnsmasq-dhcp" /var/log/pihole/pihole.log > ~/dhcp.log

where <hh> limits output to a specific hour, e.g. "Jul 11 08.*dnsmasq-dhcp" would extract all DHCP lines during Jul 11 08:00 and Jul 11 08:59.
Adjust as required, to match the time of your DHCP outage.

You could then upload that dhcp.log and share the token:

cat ~/dhcp.log | sudo pihole tricorder