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Reprotect and failback
38 Dell EMC SC Series: VMware Site Recovery Manager Best Practices | 2007-M-BP-V
8 Reprotect and failback
After virtual machines are migrated from one site to another using either the disaster recovery or planned
migration features in SRM, they are in an active running state on the network at the alternate site. However,
they are vulnerable to a site failure with no SRM protection. Previous versions of SRM required a manual
reprotection of the virtual machines at the recovery site. Today, SRM automates the reprotect process and
prepares the virtual machines for failback.
8.1 Reprotection
Once protected virtual machines are migrated, or disaster recovery failed over to the secondary site, the VMs
are unprotected. Following the migration of a protected group, SRM offers the ability to automate the
reprotection of the virtual machines. The reprotection is carried out in a series of automated steps.
Note: Prior to performing the reprotect operation in SRM, it is recommended to execute the Save Restore
Points operation in Unisphere Central as well as the Discover Devices operation in SRM for each array in the
pair.
During a reprotect, SRM commands the SRA to reverse storage replication for each of the
datastores/volumes in the protection group in the opposite direction. The protection group originally set up at
the primary site is migrated to the secondary site. Placeholder VMs originally set up at the secondary site are
now created at the opposite site (the new recovery site) on its respective placeholder datastore.
8.2 Failback
Failback is an SRM term that describes the ability to perform a subsequent disaster recovery or planned
migration after a successful recovery and reprotect. The benefit that failback introduced in SRM 5.x is the
automated ability to move back and forth between sites with minimal effort. This facilitates a number of use
cases including the ability to run production applications at the disaster recovery site, resource balancing, and
improved disaster recovery infrastructure ROI.
Note: Before executing the Failback recovery plan, it is recommended to first run a Test Recovery of the plan.