DHCP Server stopped working after power outage

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Six months ago I did follow a guide to DNSSEC with Unbound.

Expected Behaviour:

I use the DHCP in the pihole. My lease time has always been set to 1hr. I have statics assigned to nearly all of the 50 devices on my network. My pihole runs on a Pi 4 statically assigned 192.168.11.7

Actual Behaviour:

Weeks ago, I accidentally assigned .7 to my printer. Everything was great and printer kept on printing until the power went out two days ago. Today when I was troubleshooting the printer I noticed the problem and deleted the static lease. Also one of my five AppleTV's, which did not have a static assigned, will not pull an IP either. I did see two errors in the diagnostic panel. One was the printer issue and the other was some sort of eth0 error but I cleared it on accident.

I updated the pihole, ran -r, updated+ upgraded Linux, re -ran update and nothing.

Everything else is working great.

Debug Token: dbI0gIDL

Your debug log includes a small snippet of your pihole log which shows a HP device being offered IP .251. It looks like that could be your printer's current IP?

Your Apple TVs should either get the address reserved for them, or else a free address from the range you've specified. You can force it to get one by disconnecting and reconnecting it. You can watch the log live to see any DHCP traffic, with the command below, which will confirm if it's asking and being offered an IP.

sudo tail -f /var/log/pihole.log | grep DHCP

Thank you Chris. The small LCD on the printer shows the printer has self assigned a 169 address and so does the AppleTV. I am monitoring with the command provided.

I find it interesting that the .251 IP is offered despite the range being from .201 - .251 and only five or six devices would even qualify.

So it has been several days and neither device is able to pull an IP. I do not see either device listed in the tail output grepped for DHCP. Both devices still have a self-assigned 169. address.

What about other devices? Do you see them when you tail the logs for DHCP?

It appears that these devices really are not sending a DHCP broadcast, or else they live on part of your network which is blocking their broadcasts from reaching Pi-hole. Is there anything common to both of them, for example, they are both uniquely using powerline networking or are both sitting on a mesh extender, anything like that?

Try manually giving them a static IP outside of your DHCP range. Are they then visible to the rest of the network and reachable?

Is there a reason for the 1 hour lease time? This is going to cause your dozens of devices to be sending renewal broadcasts every 30 minutes. Typically you would use something longer, such as 24 hours or a week.

Static IP's were not working on either device. I even reset the printer and ATV to defaults and still nothing.

Unbelievable. I power cycled the 48-port Switch and everything is working great now. Thank you Chris.

That's a frustrating bug! Keep an eye on that switch in case it decides to give you any more surprises. Glad it's sorted now.

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