Help troubleshooting DHCP failure/IP conflict/??
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For the past ~2 weeks or so I've had an issue with several host devices in my home failing to connect, mostly wireless, mostly devices like phones or tablets that leave the house and come back, with errors on phone devices like "unable to obtain IP" or "failed to connect".
A few static wireless devices (a TV or streaming stick, or Amazon echo) have also had periodic issues connecting. And I'm now convinced that a few wired devices that had bee solid for several years are also having issues (at least one TV, an xbox series x).
I have 4 ruckus r710 access points running unleashed mode, hard wired not in mesh. I thought one of these was the problem, I upgraded firmware to latest, have reset and reconfigured all of them. I'm not sure this is the cause now.
I have a cheap TP-link unmanaged 24 port switch. Can a switch go bad in this way? I have purchased a brocade ICX-7250 48P which is on the way. Needed the expansion anyway and probably time to figure out how to properly use a managed switch.
pfsense running on Aliexpress special, integrated celeron based PC with integrated Intel gigabit NIC x 5 and one SFP. Currently version 2.4.5-release 1.
This has been stable for ~3 years.
Could pfsense be failing to hand out some IPs for some host devices? I ran a MAC debug tool on the ruckus AP management interface and could see my phone make it to DHCP and captive portal layers (I don't have any captive portal stuff setup in pfsense?), but can't tell from that what the issue is.
I thought maybe rogue DHCP somewhere on the network causing conflicts, but I'm not sure how to find it if so.
Thoughts and suggestions?
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On pfSense, under Diagnostic, you' find packet capture.
Select the LAN interface, protocol UDP and port 68 and 68.
Select high details.
And start.
From now on you'll see DHCP requests coming in, and the pfSense DHCP server answers. -
@Gertjan
Awesome, thanks. I'll enable that and see what that turns up. -
@Gertjan
And... as soon as I enabled that, my phone which hasn't been able to connect the past two days was connected just fine. Figures.It won't last though. It's been a migratory problem, some devices not connecting for a day or two, then connecting but others dropping their connection. Almost like not enough IP address available, but there should be plenty. I even expanded the DHCP range by 50 just to make sure. It will mess up again soon in some device and I'll see what that packet capture is showing.
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@rhosch Are you using Kea DHCP or ISC DHCP? If Kea, try reverting. (it's still in feature preview)
Anything in pfSense DHCP logs?
Some devices will show the DHCP server they are using. "ipconfig /all" will do so on Windows.
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@SteveITS
I've seen Kea mentioned in a few threads when searching before posting... I assume I'm on the older DHCP model. I'm using 2.4.1 but intend to update when I get a chance (I think 2.7 was what I saw as latest stable?).I'll look at DHCP logs also when I get a chance, hopefully this weekend. I did try ipconfig /all yesterday and saw only the expected pfsense IP.
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@rhosch Oh OK, 2.4 is quite old. But that doesn't mean it would stop working.
You might consider installing 2.7.2 new and restoring your backup. That will use ZFS as the file system. You won't have GUI access to boot environments as in Plus but it's more resistant to file system corruption. Installing new will also save a few upgrades as I don't think you can go from 2.4 to 2.7 without one or two extra upgrades in the middle.
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OK I finally had some time new that holiday crazy is settling back down.
I took the easy road for now and update via web GUI, had to first do deprecated 2.6 then it let me update to 2.7.2. That seemed to go smoothly.
As soon as I did my phone that had been disconnected for days connected fine. Probably doesn't mean much, I'll keep checking on devices and see if any are refusing to connect. I did start the packet capture, turned wifi on my phone off and back on and it connected again and I can see that it's showing the DHCP request/response so that will hopefully be helpful in continuing to troubleshoot assuming it wasn't a pfsense corruption issue that updating fixed.
I also got the brocade ICX7250 in so I'll start working on getting that flashed and configured for a basic setup.
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So it seems updating pfsense did in fact fix the DHCP issue. I guess something had become corrupted. I haven't had any device fail to connect since updating. I'll still get the ICX7250 ready and swap over to that when I get a chance, seems a good idea to get rid of the cheap unmanaged switch I've been using. It also has a robust POE budget which is pretty cool.