Netonix Forums

Any ideas on this (see below) and also, can I disable STP since its nothing I use not sure if it has to be running.

Port 1 is from the core router
port 3 goes to Ubiquiti backhaul out to another site.
Wondering why both have issues at the same time? And what could be issue?

Thanks! Mike


Jan 1 17:27:16 Port: link state changed to 'down' on port 1
Jan 1 17:27:16 STP: set port 1 to discarding
Jan 1 17:27:19 Port: link state changed to 'up' (1G) on port 1
Jan 1 17:27:19 STP: set port 1 to discarding
Jan 1 17:27:19 STP: set port 3 to discarding
Jan 1 17:27:19 STP: set port 1 to learning
Jan 1 17:27:19 STP: set port 1 to forwarding
Jan 1 17:27:19 STP: set port 3 to learning
Jan 1 17:27:19 STP: set port 3 to forwarding
Jan 1 17:27:20 Port: link state changed to 'down' on port 1
Jan 1 17:27:20 STP: set port 1 to discarding
Jan 1 17:27:22 Port: link state changed to 'up' (1G) on port 1
Jan 1 17:27:22 STP: set port 1 to discarding
Jan 1 17:27:24 Port: link state changed to 'down' on port 1
Jan 1 17:27:26 Port: link state changed to 'up' (1G) on port 1
Jan 1 17:27:26 STP: set port 1 to discarding
Jan 1 17:27:26 STP: set port 3 to discarding
Jan 1 17:27:26 STP: set port 1 to learning
Jan 1 17:27:26 STP: set port 1 to forwarding
Jan 1 17:27:26 STP: set port 3 to learning
Jan 1 17:27:26 STP: set port 3 to forwarding
Jan 1 20:36:17 Port: link state changed to 'down' on port 1
Jan 1 20:36:17 STP: set port 1 to discarding
Jan 1 20:36:19 Port: link state changed to 'up' (1G) on port 1
Jan 1 20:36:19 STP: set port 1 to discarding
Jan 1 20:36:20 STP: set port 3 to discarding
Jan 1 20:36:20 STP: set port 1 to learning
Jan 1 20:36:20 STP: set port 1 to forwarding
Jan 1 20:36:20 STP: set port 3 to learning
Jan 1 20:36:20 STP: set port 3 to forwarding

Hi Mike.

I would love to be of assistance here. What model of switch is this, and what version of firmware is currently installed?

Could be anything but it looks like the link is going up and down (Port 1).

Well, I am not there to debug your equipment but to me using normal basic IT skills of deduction I would say possible causes are as follows below.

I have also provided you with basic IT debugging methods to test each hypothesis.


1) Port 1 cable needs re-seated from a bad connection in the port/jack, either switch side or radio side.
Ways to determine this are obviously re-seat RJ-45

2) Bad Port 1 in switch.
I would test this by moving to another Port in switch and see if issue follow to other Port.

3) Bad cable and or End.
I would start by replacing ends and then look at cable. A cable can have a broken wire that gets intermittent connections.

4) Bad Port in device.
I would test this by replacing the device.

I do not mean to be cynical but it just amazes me how people put up a post like this and expect me to have an all knowing answer to their issue and some secret hidden command in the firmware to resolve their issue.

Now if you had provided more information about your installation and performed reasonable debugging steps like those outlined above and provided me with your results of each step I might have more of a clue and insight to your issue and could possibly provide you with a "guess" as I am not there to test anything myself as nothing beats a hands on approach.

Now why Port 3 is doing this I would suspect it has to do with RSTP but I do not know what your network topology is and why RSTP may be considering Port 3 a possible loop threat so it looks as though it is setting Port 3 to blocking/learning to make sure there is no possible loop caused by Port 1 coming up before it allows Port 3 to return to a forwarding state. Since Loops and the ensuing packet storm happens very fast this behavior makes sense, better to play it safe.

There must be a reason the switch considers Port 3 as a possible threat and goes through the loop prevention check to make sure nothing bad happens?

Its a ws-6-mini running 1.4.6 this doesn't happen very often sometimes weeks will go by with zero log files but once in awhile you see it happen.
I am aware of possible cable connection issues and that very well may be it but I wanted to rule out things like overload, pause frames, flow control or anything like that versus the connection problem. It mentions STP and is that something I can disable or do I need it running? I don't use it that I know of.
This is a very simple setup Fiber comes in to mikrotik then cat6 patch to port 1, then port 3 is a dish that goes out to feed customers.
Chris you mentioned " Port 1 cable needs re-seated from a bad connection in the port/jack, either switch side or radio side.
Ways to determine this are obviously re-seat RJ-45" but that is a simple 5 foot cat6 patch cable and doesn't go to a radio. It was a quality one but I guess it could be the seat.
Is it possible that the port 3 cable from dish is the culprit and has a bad seat? would that cause port one to go down?

Mike

No, a physical connection issue on Port 3 will have no affect on a Physical connection on Port 1.

Hopefully you do not have Port Speed/ Duplex hardcoded, NEVER hard code port speed duplex except under very rare conditions.

There is "no" possibility that this is an overload of packets as this is a switch core not a software switch. Switch cores are designed to provide full line speed on all ports.

If you suspect Flow Control you could disable Flow Control and see if issue continues but FLow Control has no effect on physical link state so I doubt it.

How do you know the MT router is not the one dropping the physical connection?

Also short pre-made jumpers can go bad and can have a broken wire or poor crimp.

nothing hard coded its all auto. I have flow off last week or two just to test because it gets no pause frames that way so I don't know in my case which one is better on or off I think im going back to on to try it out. Ive read all the hype on that at UBNT and here tough call.
Now I guess it could be the router dropping it do you mean because on the physical end (loose) or actually dropping due to the traffic or some other thing. Log files don't show anything I don't believe. I looked at those.

Mike

The link is not dropping from either side by traffic.

You're going to have to investigate it.

Checking logs in both devices.

Experimenting with cable.

Could be a bad port in either device so swapping ports on both devices one at a time.

You're just going to have to experiment and narrow it down but from what the log in the switch indicates is the physical link is dropping for what ever reason.

Make sure the port in the router is not hard coded and is set to AUTO as well.

ok I will check that out and start with fresh logs and observe next time it happens. Will check router hard code. Its a drive to get there but will change cable and ports to see what happens. Thanks!

oh yeah the stp enable setting? do I need it?

Mike

Mike wrote:ok I will check that out and start with fresh logs and observe next time it happens. Will check router hard code. Its a drive to get there but will change cable and ports to see what happens. Thanks!

oh yeah the stp enable setting? do I need it?

Mike

You only need STP/RSTP if you have the possibility of a loop other wise you can disable it.

You can learn about STP/RSTP by Google as it is a STANDARD not invented here type thing:
https://en.wikipedia.org/wiki/Spanning_Tree_Protocol
http://www.cisco.com/c/en/us/support/do ... 2-146.html

happened again last night. router logs show nothing and no dropped links. You would think router would see something if the switch does? maybe switch is more finicky. I can change that patch cable and the ports and see what happens.

Mike