Spanning Tree Questions

[david.sovereen@mercury.net]

The Cisco sends standard RSTP packets on the untagged/native VLAN, hence the Mikrotik's see and work with the Cisco just fine. The Netonix should too. It does not.

If you set up the Netonix with the VLAN and STP settings on my screenshot, it does NOT send out BPDUs on ports 1 and 2. You can try that without a Cisco.

Dave

[david.sovereen@mercury.net]

The Cisco is not the problem. I have a Cisco readily available in my lab, so that is why I used it. This bug is easily viewed in a lab with just a Netonix switch and Mikrotiks.

The Netonix switch I ordered arrived today and I labbed it out using only Mikrotiks and the Netonix. Here's how to set it up to reproduce the bug

Mikrotik-1
All ports in Bridge with mode=rstp and path cost 10 (default on Mikrotik). Set as STP root with priority=0x4000.
Mikrotik-2
All ports in Bridge with mode=rstp and path cost 10 (default on Mikrotik).
Wire up as follows:
Mikrotik-1 ether2 <-> Mikrotik-2 ether1
Mikrotik-2 ether2 <-> Netonix Port 1
Netonix Port 2 <-> Mikrotik-1 ether1
Mikrotik-1 will show ether1 and ether2 as designated ports, as it is the root bridge.

Mikrotik-2 will show ether1 as root port with path cost of 10 and ether2 as a designated port.

Netonix will show Port 1 as Forwarding / Root and Port 2 as Discarding / Alternate. It should not. The Path Cost on Port 1 is 20 and the Path Cost on Port 2 is 10, as it is directly connected to the root bridge Mikrotik-1 on Port 2. Port 2 should show as Forwarding / Root and Port 1 should show as Alternate. The cables on the Netonix can be reversed so that Port 1 goes to Mikrotik-2 and Port 2 goes to Mikrotik-1, which would reverse the path costs to root, but the Netonix always puts Port 1 in Forwarding / Root and Port 2 in Discarding / Alternate mode.

With the VLAN and STP configuration in my screenshots, the Netonix does not send BDPU or correctly process BPDUs on Ports 1 and 2.

Hope you can fix this quickly as we have many more Netonix switches to deploy, but with this STP issue, we're unable to deploy any more until this is resolved.

Thanks,

Dave

[Eric Stern]

I only have 1 Mikrotik device, can you duplicate the problem using only 1?

[Eric Stern]

If you set up the Netonix with the VLAN and STP settings on my screenshot, it does NOT send out BPDUs on ports 1 and 2. You can try that without a Cisco.

I tried this. Using a laptop running wireshark I do see STP BPDU's on ports 1 and 2.

If you can duplicate this again, maybe try setting up a Netonix from factory default and give me detailed steps on how you configured it. Or just backup the configuration off it and send it to me.

[david.sovereen@mercury.net]

Do you have two Netonix switches and a Mikrotik? You just need three RTSP speaking devices. They can all be Netonix. Brand doesn't matter. (Mikrotik is helpful because it shows the path cost to get to root, while the Netonix doesn't. It would be nice for this to be in the GUI and Console.)

Configure one as root.

Configure one Netonix switch with the VLAN and STP settings from my screenshots. Leave the others at the factory default configuration. Use ports 1 and 2 to connect the Netonix with the posted VLAN and STP settings to your other RSTP-speaking switches.

The Netonix will ALWAYS show Port 1 as Designated/Root and Port 2 as Discarding/Alternate, even if you connect Port 2 directly to the Root bridge and Port 1 has to go through a second switch to get to root.

Dave

[Eric Stern]

No luck duplicating this. I set up 3 switches as you described, it seems to work fine. Screenshots of the configuration below. Switch A is the root switch configured with VLANs. Switch B is the, I dunno, middle switch. Switch C is the "problem" switch.

Switch A port 1 -> Switch B port 1
Switch A port 2 -> Switch C port 2
Switch B port 2 -> Switch C port 1

As you can see switch C has port 2 as Root, which is the port connected to the root switch. If I swap the cables on port 1/2 then port 1 becomes Root.

I'll see about showing the path cost in the UI.

[david.sovereen@mercury.net]

To mimic my network setup and my lab setup, the root switch SHOULD NOT have the VLANs and STP settings from my screenshots. The root switch needs to be a factory default Netonix with only the root priority changed (or a Mikrotik configured per the instructions above). Note that I didn't test with a Netonix as root, only with a Cisco and a Mikrotik as root.

The other two Netonix switches SHOULD have the VLAN and STP settings in my screenshots (and in your screenshots, they do not).

Please reverse which switches have the VLAN and STP settings, you should reproduce the problem.

Thanks,

Dave

[Eric Stern]

I tried again with the VLAN/STP configuration on the two non-root switches, still can't duplicate it. I first tried a Netonix as the root switch, then the Mikrotik.

If you can duplicate it, try installing 1.4.1 and run this command at the linux command line (just copy/paste the whole line)

touch /tmp/vtss_appl_debug; /etc/init.d/vtss_appl restart; sleep 30; rm /tmp/vtss_appl_debug; /etc/init.d/vtss_appl restart

That should take about 30 seconds, then grab the /var/log/vtss_appl file and send it to me. I might be able to figure out what is going on by sifting through the debug output.

[david.sovereen@mercury.net]

Wanted to update this to let you know I'm still looking at it. I finally got a moment this afternoon to revisit this. I upgraded to 1.4.1 and could not reproduce my problem in the lab. So I downgraded to 1.4.0 and I *still* cannot reproduce my problem in the lab. What the !?

Hope to get some time to work on it tomorrow, otherwise, I'm off until Monday. Thanks for your responses on this.

Dave