Engin,
The 6.0x guide should cover everything you need on 6.0.2h
https://documentation.extremenetworks.com/networkos/SW/60x/53-1003658-01_L3RoutNetworkOS_6.0.0_CG_Ju...
Also please note, one common issue with PIM on a VCS fabric is that the VDX 6740/8770 does not support the RP role. The VDX can participate in the PIM network, but the RP must be a device outside the VCS fabric.
Thanks,
Michael Morey
Principal Technical Support Engineer – Switching, Routing & Analytics
U.S. Domestic Toll Free: +1 800-872-8440
Michael Morey
Principal Technical Support Engineer
Extreme Networks