Is it just me, or is anyone else struggling with UniFi Gateways?
Let me explain:
I have a UDM-Pro and a UX. Unfortunately, in the locations where these devices are deployed, the ISPs provide internet connections via PPPoE. Here’s the issue: for some reason, all UniFi devices seem to cap their speeds at 100 Mbps when using PPPoE. Even worse, on my UX, the WAN port doesn’t negotiate a gigabit connection—it stays stuck at 100 Mbps.
From my experience, if your ISP uses PPPoE, you should be prepared to use a modem or a small router to handle the PPPoE connection before feeding it into your UniFi gateway. I’m currently exploring router/gateway myself, but it’s honestly disappointing that such powerful devices struggle with PPPoE performance.
In my UDM-Pro setup, I have 3 WANs, all using PPPoE. That means I need to place 3 separate routers or gateways in front of the UDM-Pro to handle each connection properly.
If anyone else has dealt with this and found a good workaround, please share—I’d really appreciate the help!
Hey there.
I have a PPPoE Gigabit connection from my provider.
I have a UDM Pro Max.
I have the fibre cable terminating near my comms cabinet with a small fibre loop going into the ONT / GPON. From there, it’s ethernet directly to the UDM Pro Max.
I had to set up the VLAN to be 10 in my case, and provide the generic username and password for the provider, just like the CPE router would be working.
I get 940 Mbps down which is about max really for PPPoE, and 100 up as that’s it’s limited to by the ISP.
You don’t need to use a router per connection in front of your UDM.
Now I haven’t tried straight fibre to the UDM, with one of those ONT-on-a-Stick things, as I’ve no real need for it.
1 Like
My ISP provides internet to my site via a fibre cable and uses a media converter to deliver the internet to my UDM-PRO using ethernet cable.
Is your IPS on?
Ya, IPS is on. It works flawlessly here. The UDM Pro Max is my router, Protect NVR for about 8 2K Cameras, and has a DAC link to my main switch. IPS, multiple VLANs, Ad Blocking, multiple APs, etc., all perfect.
1 Like
I haven’t had to use PPPoE on Unifi myself but I’ve seen enough community posts to know that being limited to around 100Mbps is not a bottleneck in Unifi itself - hardware or software. The common complaint is usually that people only get around 700Mbps max on PPPoE, and I believe they have improved that in the last year or two.
The interface linking at only 100Mbps points to a cable issue, or the other side is set to 100Mbps.
2 Likes
Before I had my UDM Pro Max I flashed OpenWRT onto a FritzBox 7530 and was using that as my router with PPPoE and was only getting around the 700Mbps mark, but that device is a toy compared to the UDM Pro Max.
The CPE router ran at 940Mbps down.
The FritzBox ran at full 1GbE line speed using iperf on the LAN of course. I think the reason for the PPPoE being slower on the FriztBox was that the CPU wasn’t good enough the manage the packets going through it with the PPPoE overheat cost. This 700Mbps was even with some of the processing offloaded, thus bypassing some inspection, otherwise it ran at a measly 300Mbps. I got some more performance out of it by way of CPU scheduling too, but it was a bit of a mess really.
1 Like
Agreed, 100Mbs is going to be a failure of the two Ethernet devices to negotiate a 1Gbs link. Check the cable, and both ports with other kit switches, pcs with 1Gbs cards etc) which can show link speed
3 Likes
Agreed , faulty or bad quality cables that are shipped with CPE devices from ISPs
try setting the port speed manually 1Gbit if possible.
2 Likes
Then, maybe it’s something on the ISP’s side. I’ll need to investigate further. The cable could be an issue, so I’ll definitely check that. What my UDM-PRO is negotiating is gigabit, but it might be because there’s a media converter on my side. It’s possible there’s something on their side that’s limited to 100 Mbps.
Image attached : WAN 1 is what I am talking about here
try switching mannually the WAN1 port speed to 1G FDX ( make sure you log in from the inside of your network not from cloud, so you dont lock yourlelf out. )
you will know imediately that it works or not.
if that doesn’t work , and you have a dump 4-5 port gigabit switch ,
try connect it between the UDM pro WAN and your CPE ISP device.
if it connects at 1G , its an incompatibility or hardware port failure between the vendor box and unifi.
you could also try setting another port on your UDM pro as WAN interface and test PPPoE on the port.
Good Luck 
7/10 times is fixed by manually setting the speed.
1/10 incompatibility between hardware or hardware failure
1/10 changing the cable
1/10 actually inserting the cable story for another time lol
1 Like
Have you tried plugging directly into your connection with PC desktop/laptop and connect via pppoe, bypass your udm to verify what connection speed your getting from your ISP
1 Like
Hey, I figured out what the issue was. In my UDM PRO, the media converter was finicky—it has worked with the other router but not with the UDM PRO. As for the UX, the cable coming from the MSP end was faulty. So, I can confidently say that in both cases, the fault was on the MSP side, not on my devices. But thanks for suggesting the possible causes anyway!
