S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
You can configure a select set of VSANs (from the allowed-active list) to control access to the VSANs
specified in a trunking ISL.
connecting to switch 1, the operational allowed list of VSANs for each ISL would be as follows:
The ISL between switch 1 and switch 2 shall include VSAN 1 and VSAN 3.
The ISL between switch 2 and switch 3 shall include VSAN 1 and VSAN 2.
The ISL between switch 3 and switch 1 shall include VSAN 1, 2, and 5.
Consequently, VSAN 2 can only be routed from switch 1 through switch 3 to switch 2.
OL-16184-01, Cisco MDS SAN-OS Release 3.x
Default Allowed-Active VSAN Configuration
as an example, you can configure the list of allowed VSANs on a per-interface basis
15-5). For example, if VSANs 2 and 4 are removed from the allowed VSAN list of ISLs
Cisco MDS 9000 Family CLI Configuration Guide