Page 1 of 1

spanning tree port status "LIST"

Posted: 25 Oct 2017 02:18
by jovnas
Hi,
I have two stacked 6900 switches with OS 7.3.3.505.R01. when I do a "show spantree ports" one of my ports is in the status "LIST". I cannot find this status in the documentation. Does anyone know what the status means? When I break the ring topology by doing shutdown on one of the ring interfaces the status persists?

Re: spanning tree port status "LIST"

Posted: 25 Oct 2017 12:01
by silvio
I am not sure (and never seen it at 6900)... but I think it means listen. In STP if there is a topology change (receiving BPDU) the port is going to state listen and than to learning. In 802.1d this state are for 15 sec. in 802.1w (default in the omniswiches) this is only for a very short time (<1Sec). So I think this isn't a normal behavior. Is it possible to make a reload of the switch (or a software update)? I hope after that the issue will resolved than.
Is the port now in forwarding or in blocking for that vlan?
regards
Silvio

Re: spanning tree port status "LIST"

Posted: 02 Nov 2017 03:19
by jovnas
I would say that the port is in forwarding mode since when I enable the same vlan on two ports that is connected to the same ring there will be a loop in that vlan and the customer complains. This means that I can only activate the vlan on one port of the ring and that means no redundancy. I have not tried to reload the stack, but since I have this eroor on at least two of my stacked units I'm not sure a reload will help.
I 'm wondering if it might be a problem that the ring is connected to the same chassis? it is now connected to port 1/1/4 and 1/1/5. Would it be better to build the ring on ports 1/1/4 and 2/1/4?

Re: spanning tree port status "LIST"

Posted: 03 Nov 2017 03:04
by silvio
I think you have different spanning tree modes at your switches.
all the OmniSwitches has per default perVlan (1x1). But if you have activated the auto-fabric feature than MVRP is per default also enabled and so STP is in flat mode. You can check with show spantree cist or show spantree vlan 1.
In case off flat you should disable auto-fabric, disable mvrp and change to spantree mode per-vlan.
regards
Silvio