topic Re: General MSTP and ELRP question in ExtremeSwitching (EXOS/Switch Engine)

General MSTP and ELRP question

Anonymous — Sat, 07 Aug 2021 04:54:24 GMT

I am just starting to put my toes in the pool that is Extreme Networks and I am getting some conflicting information about Multi Spanning Tree and the Extreme Loop Recovery Protocol…

I was under the knowledge that ELRP was an option to enable in a MSTP environment to help prevent loopback events, but some of the forum posting make it sound as it ELRP is there to replace MSTP...is this correct?

Seems like ELRP is just loopback protection, but MSTP is high availability for traffic.

Just wanting to make sure im understanding everything before I screw up my lab too bad … 🙂

Re: General MSTP and ELRP question

Stefan_K_ — Mon, 09 Aug 2021 03:19:24 GMT

It depends on your network topology. If you only want a loop protection I would go for ELRP. But some networks structures require some kind of STP, e.g. with multiple edge-switches that have multiple connections between each other, like here:

Re: General MSTP and ELRP question

OscarK — Mon, 09 Aug 2021 13:39:40 GMT

The big difference is ELRP is a simple protocol where every switch sends an elrp packet and check if it comes back indicating a loop, then it can disable a port. ELRP is not aware of a topology and each switch should do ELRP.

MSTP is topology aware and can handle bigger networks as Stefan mentioned.

Nowadays you can design your network in such a way MSTP/STP is not needed and all you need is loop prevention on the edge and for such a purpose ELRP fits nicely.