You can upgrade existing Site Recovery Manager installations. The Site Recovery Manager upgrade process preserves existing information about Site Recovery Manager configurations.
For information about supported upgrade paths, see http://partnerweb.vmware.com/comp_guide2/sim/interop_matrix.php? before you upgrade.
in the VMware Product Interoperability Matrixes atTo revert to Site Recovery Manager 8.1 after upgrading to Site Recovery Manager 8.2, see Revert to a Previous Release of Site Recovery Manager.