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uberguy's profile

5 Messages

Tuesday, May 21st, 2024 6:47 PM

Slow speeds after Passthrough turned on

Yesterday I installed a new UniFi gateway. I followed the steps I found here and it is all working properly except for the download speeds are very slow compared to before I installed the gateway. Prior to the new gateway, I was running typically around 930 Mbps, now I'm averaging around 275 Mbps. Upload speeds are unchanged around 940 Mbps. I have a BGW320-500 and behind it is a UniFi Gateway Max.

Any idea where to start troubleshooting what might be causing the slow speeds? 

Accepted Solution

Scholar

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4.1K Messages

22 days ago

Maybe I misunderstood what you were asking but the UniFi Gateway shows the same external IP address that the BGW320 shows.

No you understood but look at what you typed below, you said in your post above that lead to the confusion.

The BGW320 shows the same WAN IP address as the BGW320 Broadband IPv4 Address.

We don't need to see your IP but I do see something that is technically incorrect. You should not be using 192.168.1.0 for your UniFi LAN network and also have the BGW320's LAN set to 192.168.1.0 network.

You can change either. The normal format is to have the BGW320 at 192.168.0 with the AT&T Gateway at 192.168.1.254, and then your secondary router at 192.168.2.0.

I actually have been running Speedtest Tracker from Alex Justesen in a Docker container for a few months, so the Speedtest app and location hasn't changed. 

Where is this container running today if you installed your UniFi server yesterday and where was it running before?

Dave

Scholar

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4.1K Messages

22 days ago

Any idea where to start troubleshooting what might be causing the slow speeds? 

Start by verifying that your UniFi WAN port has the dynamically assigned by AT&T as shown on this BGW320 web interface address: http://192.168.1.254/cgi-bin/broadbandstatistics.ha

Also it would be helpful to know which BGW320 LAN port you are using for your UniFi Ethernet connection and the WAN port speed on your UniFi? Note: not all device play nice with Port 1 (Blue box around port) always double check by also testing one of the Yellow Ethernet ports.

Finally which method did you select for Passthrough Mode address assignment on this page: http://192.168.1.254/cgi-bin/ippass.ha

Choices are DHCP - fixed, DHCP - dynamic, or Manual

Dave

5 Messages

22 days ago

Thank you for your quick reply, Dave.

The BGW320 shows the same WAN IP address as the BGW320 Broadband IPv4 Address.

I was using Port 1 on the BGW320. I have moved it to Port 2 which has improved the download speed up to around 650 Mbps. (That's odd.) The UniFi has a port speed of 2.5 Gbps.

I'm using DHCPS-fixed for the Passthrough Mode.

Scholar

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4.1K Messages

22 days ago

I was using Port 1 on the BGW320. I have moved it to Port 2 which has improved the download speed up to around 650 Mbps. (That's odd.) The UniFi has a port speed of 2.5 Gbps.

Port 1 does not play well with all 2.5 or 5 Gigabit Ethernet controllers since the 2.5 / 5 Gigabit specs have been a moving target that started with 2 Gbps then 10 Gbps and now most use 2.5 or 5 GB and ignore 10 GB.

If  you only have the 1 GB speed tier there is likely no benefit from using Port 1. If your neighborhood has Fiber 2000 / 5000 there may be an extra 200-300 Mbps if you are on a XGS-PON Splitter. You can check your BGW320 by looking at the Fiber Status page: http://192.168.1.254/cgi-bin/fiberstat.ha

GPON is 1310 nm for the Wave length field.

XGS-PON is 1270 nm

Dave

5 Messages

22 days ago

We do have Fiber 2000 available here but I only have the 1000. Wave Length shows 1270 nm. 

So while it's better than what it was before I changed ports, it is still 30% lower than it was prior to putting the new gateway in place. Is that to be expected? It doesn't seem like there should be that much of a performance hit from adding that piece of equipment. 

Scholar

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4.1K Messages

22 days ago

It depends on where you are testing the download from and what you are comparing before using just the BGW320 and then after UniFi install.

Are you testing from the same client device using the same speedtest server? It also matters if you are using a Speedtest app vs a web browser.  Next up what are your Firewall rules set on the UniFi since you are seeing the lower download vs a higher upload? 

The BGW320 shows the same WAN IP address as the BGW320 Broadband IPv4 Address.

This is your reply above but we need to verify the WAN IP on your UniFi. For now I will guess you just made a typo above...

You can still experiment with Port 1 and speed settings with your UniFi WAN port settings. The default should be "auto" by default.

Dave

Employee

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198 Messages

22 days ago

As he mentioned speeds of 930 I would expect it to be gpon. But yeah I would simply go through factory resetting gateway first and then set up IP passthrough with fixed dhcp on port 2, 3  or 4.

Scholar

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4.1K Messages

22 days ago

@receding_hairline member @uberguy verified the following:

Wave Length shows 1270 nm. 

So they are on an XGS-PON Splitter with a SFP Optical transceiver of 1270 nm. The issue is performance behind the UniFi in Passthrough mode. Initially it was in Port 1 with the average of 275 Mbps download. Moving to Port 2-4 downloads are about 650 Mbps.

No need for a Factory reset.

Dave

Employee

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198 Messages

22 days ago

(Edited per community guidelines) im blind. Enough screen time for me i guess.

(edited)

Scholar

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4.1K Messages

22 days ago

@receding_hairline 

It happens to members all the time including me. I usually just try to blame the (Edited per community guidelines) Forum software.

Dave

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