Media servers a MSDP/PD Disks

We just upgraded to 7.6.02.

We have two DD servers with each having its own PD.

Server - A : PD -A

Server - B : PD -B

Yesterday I noticed that restoring from an image that was backed up using Server - A to PD -A, the restore kicked off on Server - B from PD - A.

How is this possible?

Thanks,