Segregation of ISL link to the redundant fabric using or not using IVR

Hi All

I have some query based on cisco mds 9509/9506 directors. Let me now explain you what i have & what i want to achive. Our setup is not a complex one & is very straight. We have two directors 9509 (sw1 & sw2) at primary site & two mds 9506 (sw1 & sw2) at DR site. We have single prod-vsan (with storage & host ports) on primary sw2 & single DR vsan at DR sw2. We created a separate vsan which only consists of ISL connection 2 ports at sw2 (prim) & 2 ports at sw2 (DR) all the four ports are TE ports. Using IVR we made clariion A7/B7 port zone with A7/B7 port for mirror connection at DR. There are  2x 1gb link from primary site to DR site going only through primary sw2 ---> DR sw2. This means we actually do not have redundancy if my sw2 at either site goes down my mirror connection on cx4-960 breaks. Now what i am trying to do is terminate 1 x 1gb link from sw2 of both sites to Sw1 at both sites this will help me terminate 2 links to two fabrics giving me link redundancy. Doing this i also want to know would i really need IVR to setup these

Plan - A

create an Identical VSAN10 on primary sw1 & DR sw1 with only two ports in each vsan. The newly created VSAN10 will only have an one ISL port & one Storage mirror port i.e. A7 & the same at DR sw1. With this I shall establish the inter DC link from primary sw1 to DR sw1 making sure that I only have CX4-960 mirror port terminated on the new VSAN10. with this should I be able to just zone prim mirror port A7 to DR mirror port A7?... Any disadvantage do i have if i just do this instead of going with IVR. I know that the current storage port A7/B7 are part of our production VSAN where we have all the storage/host ports terminated & i can just remove the A7/B7 & assign it to the new created VSAN10. Not using an IVR like we have now will give me any advantage? we have spent quite a good amount on just acquiring IVR license but i am unable to find the reason for investing in IVR

Plan B

This is just simple like I create an identical vsan with only ISL port at both the sw1 (prim & DR) & let the mirror port at both site be where they are. Once the inter DC link is establish I just need to allow the prod VSAN to IVR vsan & then setup IVR to zone the primary mirrorport to DR mirror port.

Any suggestions to this will be really appreciated. I can also be reached at firoz_ali@jltgroup.com or +447919381259 just incase.