By default, Site Recovery Manager checks arrays for changes to device configurations by rescanning arrays every 24 hours. However, you can force an array rescan at any time.
You can reconfigure the frequency with which Site Recovery Manager performs regular array scans by changing the storage.minDsGroupComputationInterval option in Advanced Settings. See Change Storage Settings.
Configuring array managers causes Site Recovery Manager to compute datastore groups based on the set of replicated storage devices that it discovers. If you change the configuration of the array at either site to add or remove devices, Site Recovery Manager must rescan the arrays and recompute the datastore groups.