STP issue with HP and Enterasys switches.

[ciscoworlds]

Hi. I have a situation that I want to ask here, hoping to find an answer. I have a simple network with 2 HP 3800 switches and an Enterasys S8 backbone switch. HP switches use RPVST and S8 uses RSTP. I changed the STP value on S8 to "0" or "4096" to make it Root, but after many attempts, one of HP switches with default STP priority (32768) is selected as root. are these methods of STP incomparable? as I know, they switch to CST (802.1D) if they could not use the same STP version. what is your idea?

[Chrisd131313]

Hi ciscoworlds,

To my knowledge they are interoperable - a cut/paste taken from "Advanced Traffic Management Guide"...

RPVST+ interoperates with RSTP and MSTP on VLAN 1 — Because a switch running RPVST+ transmits IEEE spanning tree BPDUs, it can interoperate with IEEE RSTP and MSTP spanning tree regions, and opens or blocks links from these regions as needed to maintain a loop-free topology with one physical path between regions.

NOTE: RPVST+ interoperates with RSTP and MSTP only on VLAN 1.

HTH