[TIP] USG/Pro DHCP Stops Working

[Slaters Kustum Machines]

I had a weird issue today at a client with a USG Pro where users stopped getting IP addresses. They have 20 users and are setup on a /22, because the guy that set it up thought it would be a good idea.....Anyway, they were not out of IP addresses, but devices stopped getting addresses and started losing connection. I tried power cycling the USG from the controller, but same issue. I ended up going in and disabling the DHCP server in the controller, clicking apply and waiting for it to provision. Then turned it back on and once provisioned the issue was resolved.

 

[thecomputerguy]

I had a weird issue today at a client with a USG Pro where users stopped getting IP addresses. They have 20 users and are setup on a /22, because the guy that set it up thought it would be a good idea.....Anyway, they were not out of IP addresses, but devices stopped getting addresses and started losing connection. I tried power cycling the USG from the controller, but same issue. I ended up going in and disabling the DHCP server in the controller, clicking apply and waiting for it to provision. Then turned it back on and once provisioned the issue was resolved.

My only experience with a USG wasn't great. I spent about three hours replacing a hodge podge of random routers acting as APs with 3 UAP-LR's and a USG. The setup went through perfectly it just took awhile to make sure everything was mounted properly. I'm about to wrap things up and walk out the door and as my final task I update the firmware on the AP's. After that the AP's were stuck in a provisioning loop. The WiFi seemed to be working but I didn't trust it since the USG reported no connected AP's. I spent about 30 minutes googling trying to find a solution until I just gave up and went around to all of the AP's and manually reset them, then reset the USG and reconfigured everything as I did 2 hours prior.

I eventually got everything setup again without the provision loop. No idea, no reason, but it did delay the job by 2 more hours which I believe wouldn't have been the case if I used their existing router instead of the USG.

 

[Slaters Kustum Machines]

My only experience with a USG wasn't great. I spent about three hours replacing a hodge podge of random routers acting as APs with 3 UAP-LR's and a USG. The setup went through perfectly it just took awhile to make sure everything was mounted properly. I'm about to wrap things up and walk out the door and as my final task I update the firmware on the AP's. After that the AP's were stuck in a provisioning loop. The WiFi seemed to be working but I didn't trust it since the USG reported no connected AP's. I spent about 30 minutes googling trying to find a solution until I just gave up and went around to all of the AP's and manually reset them, then reset the USG and reconfigured everything as I did 2 hours prior.

I eventually got everything setup again without the provision loop. No idea, no reason, but it did delay the job by 2 more hours which I believe wouldn't have been the case if I used their existing router instead of the USG.

How long ago was this and where is the controller? There was an issue where using https:// in the inform URL caused this issue, but it was listed as an issue in the release documents. Overall we have had good luck with everything Unifi, but nothing is perfect.

 

[nerd2u]

So machines which had previously obtained a lease from the DHCP server lost their IP address or just new machines weren't getting addresses?



Sent from my SM-G870W using Tapatalk

 

[Slaters Kustum Machines]

So machines which had previously obtained a lease from the DHCP server lost their IP address or just new machines weren't getting addresses?



Sent from my SM-G870W using Tapatalk

Both, once leases expired, users were unable to access the network. New devices couldn't get an IP address. However anything with a static IP worked fine.

 

[YeOldeStonecat]

Firmware up to date?
Unifi controller up to date?
Any vlans?
If any vlans, what switch in the mix?
Was disable multi cast to LAN option checked?

 

[Slaters Kustum Machines]

Firmware up to date?
Unifi controller up to date?
Any vlans?
If any vlans, what switch in the mix?
Was disable multi cast to LAN option checked?

The controller is a little behind. It's on 5.6.30. It's running on their Windows server. I need to move it to our hosted controller on 5.8.24, I'm just nervous about doing the move.

No VLAN's
Block LAN to WLAN Multicast and Broadcast Data is not on. I'm not sure of any other options related to multicast.

 

[thecomputerguy]

How long ago was this and where is the controller? There was an issue where using https:// in the inform URL caused this issue, but it was listed as an issue in the release documents. Overall we have had good luck with everything Unifi, but nothing is perfect.

Probably about 3 months ago ... and all firmware was up to date.

 

[Slaters Kustum Machines]

Probably about 3 months ago ... and all firmware was up to date.

That sounds right about the time this happened, due to a firmware update. I did a quick search, but didn't find what version that changed on.