I have 2 cisco catalyst WS-C6509-E,I have to configure VSS, but this cisco switch has no modules Distributed Forwarding Card (DFC)(DFC3C (WS-F6700-DFC3C and WS-F6700-DFC3C-XL))is necessary to take these modules to implement VSS
tengo 2 cisco catalys WS-C6509-E, tengo que configurar VSS pero mis equipos no tienen tarjetas Distributed Forwarding Card (DFC), es necesario tener estos modulos para implementar VSS
see table 4-1 Hardware requirements in the following document
PFC, DFC, and CFC Requirements
The VSS supports any 67xx series switching module with CFC hardware
you can build a VSS the only limitation is that missing a WS-6708 or a WAS-6716 your VSS link can be made only of 10GE ports on the two supervisor.
if a supervisor fails the survirving supervisor may be not able to control both chassis.
if you add a WS-6708 with DFC3C on each chassis you can include 10GE ports of these linecards in the VSS bundle and so you can overcome the above limitation: if one supervisor fails the other one can control the other chassis.
Hope to help