WS-8-250-AC Loop protection

[Mola9850]

Hello

So today i had an 8 ports beginning to make loop protection, even though I only have a link to the mast.

Some here an idea why it is doing it??
It is runnig whit firmware version 1.1.0
Hope these screen shots helps

[Mola9850]

2 more

[sirhc]

Well the way that Loop Protection works is it sends a special unique packet out each port and if that packet returns on another port then it shuts the receiving port down and then turns it back ON after a predetermined period of time.

The main difference between Loop Protection and R/STP is that R/STP uses BPDU packets which are not supposed to traverse another switch but Loop Protection packets can so the packet can go out as far as it likes on a flat Layer 2 network bouncing around and work their way back any way they can find to the sending switch.

Obviously some how that packet is returning and the switch is finding it on a different port then it was sent out on?

You can try turning off Loop Protection and see if you end up with intermittent LOOPS which could be BAD NEWS.

I would turn RSTP on and then turn off Loop Protection and see if you get Loop detections from RSTP.

[sirhc]

On an unrelated issue to the OP I noticed in a screen grab above you have Flow Control turned OFF on your up-link or back haul 1G port?

For Flow Control to work you need to have it turned on all ports not just the ports going to the 10/100 AP's

You need Flow Control all the way back to a way-point or routed destination in your network.

I have many posts on this on out Forum. Turning FC on just the AP ports will not do anything as those ports are the one that will get flooded with packets since they feed a wireless link with an undetermined amount of capacity.

The switch has 4Mb of shared buffers but since the link to the AP's is 100M the switch will only allocate so much memory to the port for buffers.

The 100M port feeding the AP will get overwhelmed quickly because the network thinks it is a 100M-FD link when in reality it is has far less capacity and is only HD. The AP will get stuck from time to time on wireless retrys on poor connections not to mention the TDM protocol time slices are not part of the normal TCP protocol which is unaware of it's time slice schedule further causing unexpected packet congestion forcing more Pause back the line to the up-link port which is 1G and is allocated more memory for buffers but it to will get overwhelmed since it is feeding multiple ports that are all issuing Pauses to it so it will need to issue a Pause to the next port or hop back on the flat layer 2 network until it reach a way-point or routed destination between the original source and the final destination but since it is a routed way-point it now has authority to use the built in TCP congestion mechanisms to tell individual sending streams to slow down.

MAKE SURE TO HAVE FLOW CONTROL ON ALL PORTS BETWEEN THE ROUTER AND THE AP.