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Mappings are used to specify how SRM maps virtual machine resources on the protected site to resources on the recovery site. Site-wide mappings can be configured to map objects in the vCenter Server inventory on the protected site to corresponding objects in the vCenter Server inventory on the recovery site. Through the wizard, SRM can create the reverse objects automatically for the user. The following resources are needed:
When the user runs a recovery plan, VMware has to know in what cluster or folder the VMs should be placed and on what network they should run. Mappings need not have identical names, nor must the resources be equal on both sides. For example, two folders on the protection site can map to the same folder on the recovery site. The next section covers, by example, how one of these mappings is done.
4. Once the mappings are set, VMware offers the ability to automatically create reverse mappings. In other words, it alleviates the need to repeat the mapping process on the recovery site. If this is wanted, check the boxes shown in Figure 58 to create these mappings. Note that reverse mappings are mirror images of the original mappings. So, in this case if a recovery plan is run in the opposite direction, any VMs that were in the London_Cluster are placed in the Boston_Cluster. If there is a need to have a different mapping, do not check the boxes and instead repeat this mapping process on the recovery site.
In addition to the mappings, SRM requires assigning a placeholder datastore at each site. The datastore holds the configuration files for the placeholder, or shadow, virtual machines at the recovery site. VMware recommends using a non-replicated datastore as these placeholder VMs can be re-created by SRM if they are lost or accidentally removed. Typically, only one placeholder datastore per site is required, though more may be configured if wanted. Dell Technologies recommends configuring two for redundancy. The placeholder datastore need only be large enough to hold the configuration files for all the recoverable virtual machines. It is not a significant amount of storage, though it is perfectly acceptable to use large, existing datastores that have VMs in them. Also note that the placeholder datastores do not have to be backed by PowerFlex volumes, they only need to be available to the SRM ESXi hosts.