Constant "set port forwarding / learning / discarding"

[brock]

I have attempted disabling STP on one of the two culprit ports (link between tower 1 and tower 2). So far nothing has blown up. I hope it will stabilize the problem until the new switches arrive.

[dhuestis]

I'm getting a similar log on two WS-6-MINI switches. Any ideas?


Log:
https://drive.google.com/file/d/0B_nyZiz-fzujLWFzY2xOWnMtdm8/view?usp=sharing

[sirhc]

Well we need to have a base line so anyone in this thread with this issue please upgrade to v1.4.5rc8 and report if issue remains.

[dhuestis]

I just upgraded to v1.4.5rc8. It's still showing up in the log. What does learning/forwarding/discarding mean?

[sirhc]

I just upgraded to v1.4.5rc8. It's still showing up in the log. What does learning/forwarding/discarding mean?

This would indicate that the device in that Port keeps losing it's Ethernet link.

Please post up a screen grab of your Main Status Tab, STP Tab, Device/Status Tab, and Device/Configuration Tab
You can upload pictures by clicking the link under the Blue Post Submit button.

What device is in that port?
So this been working fine and then just started happening?

This could be from a bad cable or end connection, damaged device, or damaged port in the switch.

What would I do to try and narrow this down:
1) Reboot the device on that port, you can do this by clicking the gear on the far right side on the Status or Ports Tab and select bounce port.
2) Check the cabling and ends, could just be dirt in one of the connectors interrupting communications.
3) Check to see if that port is damaged by moving the cable to another port of the switch.

[smartmoney]

The ONLY way i could get mine to stop is factory default and rebuild from ground up. :(
I spent countless hours trying to debug and try different things,

[ste]

See some random seldom monitoring alerts behind a site.
Found the WS-12-250AC does this STP warning stuff for the feeding port.

Port1 connects a SAF Integra. This port is accessport in the same group as another port connecting the mikrotikrouter at this site. Sure no loop. The port is stable at 1GB without errors (6TB RX/TX Data).


Nov 29 05:33:14 STP: set port 1 to forwarding
Nov 29 06:07:58 STP: set port 1 to discarding
Nov 29 06:07:58 STP: set port 1 to learning
Nov 29 06:07:58 STP: set port 1 to forwarding
Nov 29 11:25:10 STP: set port 1 to discarding
Nov 29 11:25:10 STP: set port 1 to learning
Nov 29 11:25:10 STP: set port 1 to forwarding
Nov 29 12:33:14 STP: set port 1 to discarding
Nov 29 12:33:14 STP: set port 1 to learning
Nov 29 12:33:14 STP: set port 1 to forwarding
Nov 29 12:33:37 STP: set port 1 to discarding
Nov 29 12:33:37 STP: set port 1 to learning
Nov 29 12:33:37 STP: set port 1 to forwarding
Nov 29 13:45:01 STP: set port 1 to discarding
Nov 29 13:45:01 STP: set port 1 to learning
Nov 29 13:45:01 STP: set port 1 to forwarding
Nov 29 13:45:14 STP: set port 1 to discarding
Nov 29 13:45:14 STP: set port 1 to learning
Nov 29 13:45:14 STP: set port 1 to forwarding
Nov 29 13:49:31 STP: set port 1 to discarding
Nov 29 13:49:31 STP: set port 1 to learning
Nov 29 13:49:32 STP: set port 1 to forwarding

Disabled STP to see if it makes a difference.


Nov 29 14:23:47 UI: Configuration changed by admin (213.185.129.201)
Nov 29 14:23:47 UI: STP_Enable: changed from 'Enabled' to 'Disabled'
Nov 29 14:23:49 STP: set port 1 to discarding
Nov 29 14:23:50 STP: set port 2 to discarding
Nov 29 14:23:50 STP: set port 3 to discarding
Nov 29 14:23:50 STP: set port 5 to discarding
Nov 29 14:23:50 STP: set port 6 to discarding
Nov 29 14:23:50 STP: set port 7 to discarding
Nov 29 14:23:50 STP: set port 8 to discarding
Nov 29 14:23:50 STP: set port 9 to discarding
Nov 29 14:23:50 STP: set port 10 to discarding
Nov 29 14:23:50 STP: set port 11 to discarding

So let's see if this solves the problem for me.

[cwachs]

Post your results. I get these same log entries on a few of my switches. I've eventually started ignoring them since I have not found a cause or solution.

[TheHox]

I also get tons of these errors. Anywhere from 10-50 a day, on multiple ports, on multiple switches.

The network shows zero errors otherwise, as far as I can tell.

[sirhc]

If you see STP changing there has to be a reason.
Below is from one of my switches in service.

Below in red you see a link to a radio link speed dropped from 100M to 10M
Nov 25 09:31:11 switch[2903]: unexpected link change on port 15 (HC22 M2 AP) from 100M-F to 10M-F
Since the link state had to go down and thus STP discarding and back up to change speed STP goes through its normal protection steps
Nov 25 09:31:14 STP: set port 15 to learning
Nov 25 09:31:14 STP: set port 15 to forwarding

Below you can see where the link was forced or went DOWN and STP then set port to discarding
Nov 25 09:31:34 Port: link state changed to 'down' on port 15
Nov 25 09:31:34 STP: set port 15 to discarding

Below you can see the port was brought back up and it negotiated at the desired 100M speed so STP has to go through the loop protection steps
Nov 25 09:31:36 Port: link state changed to 'up' (100M-F) on port 15
Nov 25 09:31:36 STP: set port 15 to discarding
Nov 25 09:31:38 STP: set port 15 to learning
Nov 25 09:31:38 STP: set port 15 to forwarding
With STP any time there is a link disruption STP will cycle through the discarding, learning, forwarding stages.

If you have a backup route that STP is normally holding as discarding to prevent a loop this can affect what happens as well.

If you have a link that has a loose end or intermittent connection this can cause STP to constantly cycle.

You need to find out what is tripping RSTP.