rstp root bridge question

[jma]

We have replaced all our UBNT Toughswitches in our network (10 in total) with WS6-MINI switches. Identified one root bridge with priority 20480, all the other switches are in priority 32768. There are no loops in the network. All but two switches identify the correct root bridge in the tab STP. The two switches that do not identify their own mac address both as bridge Id and root bridge Id. Is there something wrong in our setup or is this a normal behavior?

[mike99]

Does the STP show the ports you expect to be forwarding and bloquing ? Just to know if it's cosmetic only.

[jma]

At the moment yes, but it took a long time and lots of learning and blocking. The ports on that two switches are all 'designated forwarding'.

[mike99]

So the're no loop for STP to handle on those switch ?

[jma]

at the moment none, we are planning to connect backup point-to-point connections though.

[jma]

One switch that does not see the root is really giving us problems. Every hour or so it blocks the port of a sector antenna that is attached to it. There is absolutely no loop in the entire network so we have no idea why it is doing this. We see this in the log:

Feb 11 06:13:07 STP: set port 4 to learning
Feb 11 06:13:17 STP: set port 4 to discarding
Feb 11 06:13:32 STP: set port 4 to learning
Feb 11 06:13:47 STP: set port 4 to forwarding
Feb 11 06:20:31 STP: set port 4 to discarding
Feb 11 06:20:45 STP: set port 4 to learning
Feb 11 06:20:53 STP: set port 4 to discarding
Feb 11 06:21:08 STP: set port 4 to learning
Feb 11 06:21:23 STP: set port 4 to forwarding
Feb 11 07:09:30 STP: set port 4 to discarding
Feb 11 07:09:44 STP: set port 4 to learning
Feb 11 07:09:54 STP: set port 4 to discarding
Feb 11 07:10:08 STP: set port 4 to learning
Feb 11 07:10:15 STP: set port 4 to discarding
Feb 11 07:10:29 STP: set port 4 to learning
Feb 11 07:10:37 STP: set port 4 to discarding
Feb 11 07:10:51 STP: set port 4 to learning
Feb 11 07:10:59 STP: set port 4 to discarding
Feb 11 07:11:13 STP: set port 4 to learning
Feb 11 07:11:21 STP: set port 4 to discarding
Feb 11 07:11:35 STP: set port 4 to learning
Feb 11 07:11:43 STP: set port 4 to discarding
Feb 11 07:11:57 STP: set port 4 to learning
Feb 11 07:12:05 STP: set port 4 to discarding
Feb 11 07:12:19 STP: set port 4 to learning
Feb 11 07:12:27 STP: set port 4 to discarding
Feb 11 07:12:41 STP: set port 4 to learning
Feb 11 07:12:49 STP: set port 4 to discarding
Feb 11 07:13:03 STP: set port 4 to learning
Feb 11 07:13:08 STP: set port 4 to discarding
Feb 11 07:13:23 STP: set port 4 to learning
Feb 11 07:13:38 STP: set port 4 to forwarding
Feb 11 07:13:52 STP: set port 4 to discarding
Feb 11 07:14:07 STP: set port 4 to learning
Feb 11 07:14:22 STP: set port 4 to forwarding
Feb 11 07:14:36 STP: set port 4 to discarding
Feb 11 07:14:51 STP: set port 4 to learning
Feb 11 07:15:02 STP: set port 4 to discarding
Feb 11 07:15:16 STP: set port 4 to learning
Feb 11 07:15:25 STP: set port 4 to discarding
Feb 11 07:15:39 STP: set port 4 to learning
Feb 11 07:15:54 STP: set port 4 to forwarding
Feb 11 07:16:06 STP: set port 4 to discarding
Feb 11 07:16:51 STP: set port 4 to learning
Feb 11 07:16:51 STP: set port 4 to discarding
Feb 11 07:17:06 STP: set port 4 to learning
Feb 11 07:17:21 STP: set port 4 to forwarding
Feb 11 07:17:34 STP: set port 4 to discarding
Feb 11 07:17:49 STP: set port 4 to learning
Feb 11 07:17:56 STP: set port 4 to discarding
Feb 11 07:18:11 STP: set port 4 to learning
Feb 11 07:18:23 STP: set port 4 to discarding
Feb 11 07:18:37 STP: set port 4 to learning
Feb 11 07:18:49 STP: set port 4 to discarding
Feb 11 07:19:03 STP: set port 4 to learning
Feb 11 07:19:15 STP: set port 4 to discarding
Feb 11 07:19:29 STP: set port 4 to learning
Feb 11 07:19:41 STP: set port 4 to discarding
Feb 11 07:19:55 STP: set port 4 to learning
Feb 11 07:20:07 STP: set port 4 to discarding
Feb 11 07:20:21 STP: set port 4 to learning
Feb 11 07:20:33 STP: set port 4 to discarding
Feb 11 07:20:47 STP: set port 4 to learning
Feb 11 07:20:59 STP: set port 4 to discarding
Feb 11 07:21:13 STP: set port 4 to learning
Feb 11 07:21:23 STP: set port 4 to discarding
Feb 11 07:21:38 STP: set port 4 to learning
Feb 11 07:21:53 STP: set port 4 to forwarding
Feb 11 08:06:30 STP: set port 4 to discarding
Feb 11 08:06:44 STP: set port 4 to learning
Feb 11 08:06:56 STP: set port 4 to discarding
Feb 11 08:07:10 STP: set port 4 to learning
Feb 11 08:07:20 STP: set port 4 to discarding
Feb 11 08:07:34 STP: set port 4 to learning
Feb 11 08:07:46 STP: set port 4 to discarding
Feb 11 08:08:00 STP: set port 4 to learning
Feb 11 08:08:12 STP: set port 4 to discarding
Feb 11 08:08:26 STP: set port 4 to learning
Feb 11 08:08:38 STP: set port 4 to discarding
Feb 11 08:08:52 STP: set port 4 to learning
Feb 11 08:09:04 STP: set port 4 to discarding
Feb 11 08:09:18 STP: set port 4 to learning
Feb 11 08:09:28 STP: set port 4 to discarding
Feb 11 08:09:43 STP: set port 4 to learning
Feb 11 08:09:58 STP: set port 4 to forwarding
Feb 11 08:10:41 STP: set port 4 to discarding
Feb 11 08:10:55 STP: set port 4 to learning
Feb 11 08:11:07 STP: set port 4 to discarding
Feb 11 08:11:22 STP: set port 4 to learning
Feb 11 08:11:34 STP: set port 4 to discarding
Feb 11 08:11:48 STP: set port 4 to learning
Feb 11 08:12:00 STP: set port 4 to discarding
Feb 11 08:12:14 STP: set port 4 to learning
Feb 11 08:12:23 STP: set port 4 to discarding
Feb 11 08:12:37 STP: set port 4 to learning
Feb 11 08:12:47 STP: set port 4 to discarding
Feb 11 08:13:01 STP: set port 4 to learning
Feb 11 08:13:11 STP: set port 4 to discarding
Feb 11 08:13:25 STP: set port 4 to learning
Feb 11 08:13:34 STP: set port 4 to discarding
Feb 11 08:13:48 STP: set port 4 to learning
Feb 11 08:13:56 STP: set port 4 to discarding
Feb 11 08:14:10 STP: set port 4 to learning
Feb 11 08:14:20 STP: set port 4 to discarding
Feb 11 08:14:34 STP: set port 4 to learning
Feb 11 08:14:42 STP: set port 4 to discarding
Feb 11 08:14:56 STP: set port 4 to learning
Feb 11 08:15:06 STP: set port 4 to discarding
Feb 11 08:15:20 STP: set port 4 to learning
Feb 11 08:15:24 STP: set port 4 to discarding
Feb 11 08:15:39 STP: set port 4 to learning
Feb 11 08:15:46 STP: set port 4 to discarding
Feb 11 08:16:01 STP: set port 4 to learning
Feb 11 08:16:08 STP: set port 4 to discarding
Feb 11 08:16:23 STP: set port 4 to learning
Feb 11 08:16:30 STP: set port 4 to discarding
Feb 11 08:16:45 STP: set port 4 to learning
Feb 11 08:16:52 STP: set port 4 to discarding
Feb 11 08:17:07 STP: set port 4 to learning
Feb 11 08:17:14 STP: set port 4 to discarding
Feb 11 08:17:29 STP: set port 4 to learning
Feb 11 08:17:36 STP: set port 4 to discarding
Feb 11 08:17:51 STP: set port 4 to learning
Feb 11 08:17:58 STP: set port 4 to discarding
Feb 11 08:18:13 STP: set port 4 to learning
Feb 11 08:18:20 STP: set port 4 to discarding
Feb 11 08:18:35 STP: set port 4 to learning
Feb 11 08:18:42 STP: set port 4 to discarding
Feb 11 08:18:57 STP: set port 4 to learning
Feb 11 08:19:04 STP: set port 4 to discarding
Feb 11 08:19:19 STP: set port 4 to learning
Feb 11 08:19:26 STP: set port 4 to discarding
Feb 11 08:19:41 STP: set port 4 to learning
Feb 11 08:19:52 STP: set port 4 to discarding
Feb 11 08:20:06 STP: set port 4 to learning
Feb 11 08:20:14 STP: set port 4 to discarding
Feb 11 08:20:28 STP: set port 4 to learning
Feb 11 08:20:36 STP: set port 4 to discarding
Feb 11 08:20:50 STP: set port 4 to learning
Feb 11 08:20:58 STP: set port 4 to discarding
Feb 11 08:21:12 STP: set port 4 to learning
Feb 11 08:21:20 STP: set port 4 to discarding
Feb 11 08:21:34 STP: set port 4 to learning
Feb 11 08:21:42 STP: set port 4 to discarding
Feb 11 08:21:56 STP: set port 4 to learning
Feb 11 08:22:04 STP: set port 4 to discarding
Feb 11 08:22:18 STP: set port 4 to learning
Feb 11 08:22:27 STP: set port 4 to discarding
Feb 11 08:22:41 STP: set port 4 to learning
Feb 11 08:22:56 STP: set port 4 to forwarding
Feb 11 08:23:11 STP: set port 4 to discarding
Feb 11 08:23:26 STP: set port 4 to learning
Feb 11 08:23:41 STP: set port 4 to forwarding
Feb 11 08:23:55 STP: set port 4 to discarding
Feb 11 08:24:40 STP: set port 4 to learning
Feb 11 08:24:42 STP: set port 4 to discarding
Feb 11 08:24:56 STP: set port 4 to learning
Feb 11 08:25:11 STP: set port 4 to forwarding
Feb 11 08:25:24 STP: set port 4 to discarding
Feb 11 08:25:39 STP: set port 4 to learning
Feb 11 08:25:46 STP: set port 4 to discarding
Feb 11 08:26:01 STP: set port 4 to learning
Feb 11 08:26:08 STP: set port 4 to discarding
Feb 11 08:26:23 STP: set port 4 to learning
Feb 11 08:26:30 STP: set port 4 to discarding
Feb 11 08:26:45 STP: set port 4 to learning
Feb 11 08:26:52 STP: set port 4 to discarding
Feb 11 08:27:07 STP: set port 4 to learning
Feb 11 08:27:14 STP: set port 4 to discarding
Feb 11 08:27:29 STP: set port 4 to learning
Feb 11 08:27:36 STP: set port 4 to discarding
Feb 11 08:27:51 STP: set port 4 to learning
Feb 11 08:28:02 STP: set port 4 to discarding
Feb 11 08:28:16 STP: set port 4 to learning
Feb 11 08:28:26 STP: set port 4 to discarding
Feb 11 08:28:40 STP: set port 4 to learning
Feb 11 08:28:51 STP: set port 4 to discarding
Feb 11 08:29:05 STP: set port 4 to learning
Feb 11 08:29:15 STP: set port 4 to discarding
Feb 11 08:29:30 STP: set port 4 to learning
Feb 11 08:29:45 STP: set port 4 to forwarding

[Eric Stern]

Maybe try swapping a Toughswitch back in for the problem switch and see if it has the same problem?

[mike99]

VLAN and STP tab screenshot would help with a schema of how switch are connected togheter.

By PTP, do you mean a PTP wireless link ? If so, is STP activated on the device ? If so, could you try disable it. The wireless link should be a true bridge that only pass through BPDU except for special case like 2 cables to the radio and you want automatic fail over between the 2 cables.

[jma]

screenshots from one of the two switches that do not recognize the rood switch. There are indeed PTP wireless links between the switches. No redundancy yet. So just one antenna receiving in every switch. There is at least one sector antenna attached to every single switch also. But there is absolutely no way to the root bridge than via the PTP wireless links. No loops possible. I really can not seen any reason why 2 out of 10 switches behave like that.

https://www.dropbox.com/s/vujk4e6cv9f93 ... 1.png?dl=0
https://www.dropbox.com/s/x5edqbnjuk9uz ... 0.png?dl=0

[jma]

I have just witnessed the switch recognizing the root switch but the result is then that the switch discards the Sector Antenna port (port 5). And after a while it reverts back to not recognizing the root switch, forwarding port 5 again. We have now disabled stp on that switch because it causes too many problems. I see this in the log. I really would like to know what is causing this.

Feb 12 13:37:32 STP: set port 5 to discarding
Feb 12 13:37:47 STP: set port 5 to learning
Feb 12 13:37:56 STP: set port 5 to discarding
Feb 12 13:38:11 STP: set port 5 to learning
Feb 12 13:38:16 STP: set port 5 to discarding
Feb 12 13:38:46 STP: set port 5 to learning
Feb 12 13:39:01 STP: set port 5 to forwarding
Feb 12 13:39:21 STP: set port 5 to discarding
Feb 12 13:40:05 STP: set port 5 to learning
Feb 12 13:40:06 STP: set port 5 to discarding
Feb 12 13:40:20 STP: set port 5 to learning
Feb 12 13:40:28 STP: set port 5 to discarding
Feb 12 13:40:43 STP: set port 5 to learning
Feb 12 13:40:49 STP: set port 5 to discarding
Feb 12 13:41:34 STP: set port 5 to learning
Feb 12 13:41:35 STP: set port 5 to discarding
Feb 12 13:41:49 STP: set port 5 to learning
Feb 12 13:41:59 UI: Configuration changed by 192.***.***.***
Feb 12 13:41:59 UI: STP_Enable: changed from 'Enabled' to 'Disabled'
Feb 12 13:42:00 STP: set port 2 to discarding
Feb 12 13:42:00 STP: set port 3 to discarding
Feb 12 13:42:00 STP: set port 5 to discarding