MSTP configuration

I am configuring MSTP in nortel Layer2 switches. Created 2instances but in both only 1 switch is acting as Root Bridge. I would like to know whether MSTP works with 2switches & the configuration as well.

Thanks

I would like to know whether MSTP works with 2switches

MSTP works even with one switch... It doesn't make sense but it works.

Created 2instances but in both only 1 switch is acting as Root Bridge.

Do you mean that only one switch is seen as root bridge per instance? And it is the same on the two switches? In this case everything is OK. You can only have one root bridge per instance.

If you mean that each switch is seen as root bridge in each instances, you probably have missed something... The MSTP configuration must be the same on the two switches. Additionally, you must have a trunk (with the vlans associated to your MSTP instances) configured between your two switches (tagged port in Nortel jargon).