loop protection - DellN3000 series switch

Question

Hi all,

I’m new to the Dell networking environment and have a question about spanning tree/root guard/loop protection.

I have noticed a small issue that I am hoping someone may be able to offer up some support. I have just setup my network as a complete dell environment.

the issue is, when I have switch1 and Switch2 connected by 2 copper lines it kills the network. The port goes from a blocked to learning mode from what I can make out from the logs. On a Cisco switch, rather than killing the network, Cisco would simply disable the port if spanning tree was turned on, however, this does not seem to be the case with Dell and I’m assuming something will be needed to allow the switch to block the port rather than start an election (assuming that is what is going on). I have tried bpdu protection and loop guard protection commands with no success. I’d like to get to the bottom of this to avoid a tech accidentally connecting 2 copper connections causing the network to halt.

DELL-Josh Cr · Answer

Hi, Which spanning tree mode are you using? Is the switch firmware up to date? How are the ports configured? Which switch is the root? It should block on port like you said.

iHaag255 · Answer

Which spanning tree mode are you using? Rpst+
Is the switch firmware up to date? Yes
How are the ports configured? spanning-tree Portfast access

Which switch is the root? A PowerConnect that the switch connects into

switch ports are trunked

DELL-Josh Cr · Answer

Have you tried turning off portfast? Since that will cause the ports to skip the learning phase.

iHaag255 · Answer

Solution was to turn of bpdu filter it was conflicting

Networking General

loop protection - DellN3000 series switch

Was this post helpful?