Hi Krishna,
If the vsconfig set command works and you have run it with a (domain) user with enough permissions on the vcentrer, yet you can't see the rdm lun's, I would test to see whether snapdrive is aware that it is installed on a virtual machine, vmtools are installed and then test creation of a small rdm lun from within snapdrive gui or sdcli, using esx initiators...
If that does not work, there could be a number of reasons for this. You are probably better off filing a case with our support, as they need to look at the encrypted snapdrive virtualization.api log.
To answer the question, the firewall between snapdrive server and vcenter server should be open , but also between snapdrive and storage system hosting the lun's mapped to esx initiators...
There is a kb on the support site, showing all ports to be open for snapdrive to work correctly. I am mobile at the moment but you should be able to find it by searching. If you suspect the firewall, I advice to disable temporarily the firewall to see if it works first, then re-enable it and open the ports.
Hope it gets you further.
