SDX slow when multiple WANS in use for download

Product Discussion Peplink Balance
1

I recently installed a peplink balance SDX to replace my balance 380 that died out of the blue. The issue I am facing right now is whenever multiple WANs are in use and downloading (I have a total of 3 at the moment) the overall download throughput becomes less than with one WAN in use.

For example, I run a speed test using WAN 1 and I get 450mbps, I run a speed test with WAN 2 and I get 450mbps.

PC 1 is using WAN 1 through the outbound policy enforce, testing a file download it achieves the same result as I got for the speed test with WAN 1.

PC 2 is using WAN 2 through the outbound policy enforce, testing a file download it also achieves the same result as I got for the speed test with WAN 2.

If PC 1 and PC 2 download at the same time, overall download throughput is less than 450 combined, WAN 1 caps at 150-200, WAN 2 caps at 80-90. If I stop the download on one device than the throughput returns to normal for the device that is currently downloading.

The same issue arises when using the Weighted outbound policy on a single PC. So when one PC is using weighted balance for both WAN 1 and WAN 2 overall download speed is less than when just using the Enforce policy with a single WAN.

I did not have this issue with the Balance 380 and from my understanding the SDX should have 12 times the throughput of the Balance 380.

Things I have already tried:

  1. Changing the port speed of all WAN/LAN ports from Auto to 1Gbps full duplex.
  2. Trying different combination of WAN ports and WAN selection on outbound policy.
  3. Enabling Speedfusion/Disabling (no difference). (Did not have this active with my Balance 380 so I thought it might be affecting it)
  4. Enabling/Disabling In Control (Also did not have this active with my balance 380)

Also I have eliminated my home network as a possible cause. Connected all devices directly to the SDX router for testing.

Would appreciate any support.

Edit: I went ahead and created a ticket with support, will update this thread if a solution is found.

2

What type of WANs are you using?

1 Like
3

Im using the two gigabit ethernet wan ports and the third is a ethernet lan port converted to wan using a license.

5

Apologies. I meant what type of internet access WANs do you have?
DSL, Fiber, Starlink, 5g?

1 Like
6

Two 5G connections and one cable.

7

It’s going to be challenging to get to the bottom of this I think without good visibility of WAN metrics. What 5G modem/routers are you using?

I’d suggest you turn on SpeedFusion Cloud and run speedtests over Speedfusion bonding. You’ll then be able to monitor realtime stats on each WAN as you load them up (in Status > Speedfusion) and that will likely help us see what the underlying cause is.

1 Like
8

Thanks for the replies Martin it seems the underlying issue was firmware 8.4.1 after reading a couple of posts on there with people having speed issues and reverting to 8.4.0 solved it for them I went ahead and tried it out myself. Here are the results, first photo is on firmware 8.4.1 when attempting downloads on two different devices using two different WANS, second photo is firmware 8.4.0.

WAN 1 + 2 Working Together Peplink Screen
WAN 1 + 2 Working Together Peplink Screen1104×1040 44 KB

Screenshot 2024-04-26 152446
Screenshot 2024-04-26 152446979×1247 56.8 KB

9

Not seen this at all. @sitloongs are you aware of any bug logged about this?

If it is firmware related we need to get a ticket logged and the issue fixed because that’s crazy.

Bet @Eddy_Yeung would be interested too.

1 Like
10

Yeah hopefully this gets resolved for now I am staying on 8.4. Also I have another issue which I posted another topic about. I would not be surprised if they were related although that one is still present in 8.4, 8.3, and 8.2.1 on the SDX, not present on my older Balance 380. I have also opened a ticket regarding this but unfortunately the techs they assigned to it are giving back generic responses.