Enabling STP on RT-AX88U

[ciprian.trofin]

To enable STP on router - do I have to do something else than go admin interface - Advanced Settings - LAN - Switch Control - Spanning-Tree Protocol - ENABLE ?

I'm asking because if I SSH the router and enter

brctl show

I get

bridge name     bridge id               STP enabled     interfaces
br0             8000.3c7c3fdc4558       no              eth1
                                                        eth2
                                                        eth3
                                                        eth4
                                                        eth5
                                                        eth6
                                                        eth7

Is STP enabled or not ?

 

[eibgrad]

Try doing it manually.

brctl stp br0 on

 

[ciprian.trofin]

@eibgrad: thank you.

I did as you instructed me and I think it works - Wireshark running on a laptop (wirelessly connected to network) shows STP packets when STP is enabled manually (via brctl); the STP packets stop showing when the STP is disabled with

brctl stp br0 off

I don't know if it solves my underlying problem (not discussed here), but hey! at least I can see STP packets flowing

However, it also looks like:
1. there are no STP packets flowing when STP is enabled only via Switch Control; bug, maybe?
2. rebooting the router disables STP; is there any way to enable it at boot time?

 

[eibgrad]

May very well be a bug. If manually enabling it works, I suppose you could add the command as an init-start script.

 

[Ripshod]

May very well be a bug. If manually enabling it works, I suppose you could add the command as an init-start script.

I have the same issue with an RT-BE88U. In this case though it gets reset to "no" at some point. I have the command in init-start - could I move this to services-start which gets called several times a day?

 

[Ripshod]

I have the same issue with an RT-BE88U. In this case though it gets reset to "no" at some point. I have the command in init-start - could I move this to services-start which gets called several times a day?

Answered this myself. Yes, adding to services-start rather than init-start has STP active constantly (well, as often as I'm checking it right now).

 

[aru]

Thank you for sharing. I have enabled STP on the main router and all nodes via commands. If a network loop occurs or if the physical network speed drops from 1G to 100M, I will receive STP topology change messages. Therefore, receiving topology change messages is the first step in identifying network issues. Like this:

Main:

Nodes:

I'm also quite curious, like ciprian.trofin asked, why is the STP result shown by the brctl show command inconsistent with what is displayed on the web UI?

 

[Ripshod]

why is the STP result shown by the brctl show command inconsistent with what is displayed on the web UI?

Who knows. I learned early on not to ask myself questions like that for fear of just frustrating myself.
I wonder how long it's been like this, and how many routers are affected. So many peeps unaware - I only investigated when I got a new managed switch, where activating stp slowed routing to a crawl while the cpu was constantly topped out.

 

[Squall Leonhart]

Who knows. I learned early on not to ask myself questions like that for fear of just frustrating myself.
I wonder how long it's been like this, and how many routers are affected. So many peeps unaware - I only investigated when I got a new managed switch, where activating stp slowed routing to a crawl while the cpu was constantly topped out.

AX88U, AC88U, AC86U, AC68U

the question may well be, what ones are not affected.

 

[ColinTaylor]

@RMerlin The merge with GPL 388_24353 on 19/12/2023 added this condition in lan.c which prevents STP being set on br0 for most HND models.

asuswrt-merlin.ng/release/src/router/rc/lan.c at f1ecc8bb70e3b76589ef46a9c824819c67b090c3 · RMerl/asuswrt-merlin.ng

Third party firmware for Asus routers (newer codebase) - RMerl/asuswrt-merlin.ng

github.com

I guess the thinking was that the following hnd_set_hwstp(); would take care of this but that does not seem to be the case as I see no STP traffic on the LAN.

 

[RMerlin]

@RMerlin The merge with GPL 388_24353 on 19/12/2023 added this condition in lan.c which prevents STP being set on br0 for most HND models.

asuswrt-merlin.ng/release/src/router/rc/lan.c at f1ecc8bb70e3b76589ef46a9c824819c67b090c3 · RMerl/asuswrt-merlin.ng

Third party firmware for Asus routers (newer codebase) - RMerl/asuswrt-merlin.ng

github.com

I guess the thinking was that the following hnd_set_hwstp(); would take care of this but that does not seem to be the case as I see no STP traffic on the LAN.

Since hnd_set_hwstp() is closed source, I have no idea what the logic is within that function. I have to trust that Asus did things this way for a reason.