"Additional Latency" to make hot backup

[Chris5342]

Am I right in thinking that "Additional Latency" (Network -> Interfaces -> WAN? -> Edit) is the only way to tell OMR to de-prefer a WAN interface (hot backup) ?

Also is "Additional Latency" only applied after a reboot ?

What am I trying to do ?

I'm trying to stop OMR putting my slow B/W low latency ADSL into bat and prefer the Starlink interface unless Starlink is have problems.

Why does this matter ?

During a video call OMR seems to keep putting the ADSL in and out (as the ADSL and Starlink latency are similar I assume).

Snag is when Starlink is put back there is a dip and seemingly the video call goes weird. See image:

Notice that the upload link via Starlink seems stable but the download keeps switching between Starlink and ADSL but that there are gaps before Starlink takes over.

What have I tried ?

Making ADSL backup - no luck that kills everything

Setting ADSL "Additional Latency" to 300 seems to work and that stops ADSL being used

Setting ADSL "Additional Latency" to 80 doesn't seem to help

Is there a way for me to see what OMR is doing (logs etc) ?
Eg why is it putting ADSL into bat ?

[Ysurac]

Additional Latency is only here for tests, should not be used.
Connections are used based on latency, when connection is fully used this used next connection with higher latency. Shouldn't need any customization in most case.

[Ysurac]

I don't understand what is the problem.
Try with "omr-test-speed" via SSH on the router, you should see that all connections are used when needed.

[Chris5342]

@Ysurac I continue to monitor. Occasionally I get odd things eg:

Thu May 26 12:35:19 2022 user.notice post-tracking-post-tracking: wan1 (wan1) switched off because No access to server API
Thu May 26 12:35:19 2022 user.notice post-tracking-post-tracking: Delete default route via 192.168.1.254 dev wan1

Thu May 26 12:36:00 2022 user.notice post-tracking-post-tracking: wan1 (wan1) switched up

wan1 is supposedly slow stable ADSL.
What does "switched off because No access to server API" mean ?

Also I captured this:

Traffic is simulated video conference, approx 1.8Mbs down 1.4Mbps up.

It seems to show that ADSL was not put into bat when Starlink had a 4s outage - but ADSL may have been coincidentally down at the time:

Thu May 26 12:09:49 2022 user.notice post-tracking-post-tracking: wan1 (wan1) switched off because No access to server API
Thu May 26 12:09:49 2022 user.notice post-tracking-post-tracking: Delete default route via 192.168.1.254 dev wan1

Thu May 26 12:09:59 2022 user.notice post-tracking-post-tracking: wan1 (wan1) switched up.

Could I add my own more detailed logging ?
If so where is the code that decide what interface to use ?

[Ysurac]

The no access to server API, mean it don't have answer from VPS API (there is an API on server side).
You can try to disable HTTP API test in System->OpenMPTCProuter, "advanced settings" tab and disable http ping to API checkbox
But API should always answer...

[Chris5342]

@Ysurac
Could this be what's happening ?

Starlink goes down.
OMR sends all the traffic to ASDL
ADSL saturates
OMR ADSL http API test fails (because the link is saturated)
ADSL is dropped

(A cascade falilure)

I will continue to monitor

[Ysurac]

Possible, you can try to enable SQM and set download and upload speed on ADSL link via the wizard. This should help to doesn't have ADSL link saturated.