IS-IS IGP is running in backbone.
Eg .router isis XYZ
and now we want to define MPLS-TE inside the backbone.
the MPLS-IGP configuration can done under router isis XYZ or we should chosse different isis process.
Eg. router isis ABC.
It has to be done in router isis XYZ. You want to enable traffic engineering on the IS-IS process that is running in your backbon
You can use same ISIS process but enble MPLS traffic engineering under ISIS process:
use these commands:
metric-style wide mpls traffic-eng router-id xxxxxmpls traffic-eng [level-1 | level-2 |]
Some more covered here: