Slow backup performance to an EMC SAN
Slow backup performance to an EMC SAN can be cause by an older version of the Flare OS. Older versions of Flare OS do not support the newer versions of VDDK that vRanger are uses which is provided by VMware.
If you are running vRanger 5.0 or above an upgrade to Flare OS version 5.0.1 or greater should resolve your issue.