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3500yl STP and DL 385 dual connection during POST

Occasional Advisor

3500yl STP and DL 385 dual connection during POST

I have a test network of 4 switches meshed in ring style. I have different DL 385's both NIC's connected to different switches and STP enabled. When DL 385 boots, during POST(iLo related?) switches start recalculating STP and blocks some ports. I checked that DL 385 does not leak traffic from one card to another while booting, maybe it is related to very similar MAC address of two NIC's in the same machine and HP3500yl thinks that two very similar macs appeared on different ports must be a loop and starts blocking..?

would appreaciate any thoughs, thank you.
Matt Hobbs
Honored Contributor

Re: 3500yl STP and DL 385 dual connection during POST

Make sure that on those 'edge' ports you set the spanning-tree mode to edge"

(config)#spanning-tree edge-port

MSTP defaults to edge-port no, whereas on the older switches that supported RSTP, edge-port defaulted to yes.

Re: 3500yl STP and DL 385 dual connection during POST

Are you sure that it not only transition the states, but also blocks port (I mean, ports that where previously not blocked, and transitioned to forward after the boot)?

OTOH, how exactly did you check that the DL385 does not "leak" traffic from one port to the other during boot?

I am very curious because I had a different but related problem with a big IBM server, which was configured for trunking and worked well for years, until it was power-cycled and caused a loop. The IBM tecnician that checked it says that it booted with the exact configuration it had before. I am beginning to worry that some multi-nic servers might leak packets from one port to another during boot.

Having two consecutive MAC addresses is perfectly normal, and is never a problem. There are servers (Sun) that have the very same MAC address on many interfaces, and this can be problematic, but not for the STP protocol.