For array-based protection, Virtual Volumes protection, and vSphere Replication protection, Site Recovery Manager applies inventory mappings to all virtual machines in a protection group when you create that group.

Site Recovery Manager creates a placeholder virtual machine when you create an array-based, Virtual Volumes, or vSphere Replication protection group. Site Recovery Manager derives the resource assignments for the placeholder from the site-wide inventory mappings.

If you configure site-wide inventory mappings, you can reapply the inventory mappings to a protection group whenever necessary, for example if you add new virtual machines to an existing protection group.

If you change the site-wide inventory mappings for a site, by default the changes affect virtual machines that Site Recovery Manager already protects in an existing protection group. Site Recovery Manager updates recovery target (folder, resource pool, or network) for all protected virtual machines to reflect the concrete mapping change. You can control this feature through the replication.updateVmProtectionOnInvMappingChange advance setting. The advanced setting is activated by default.

Site Recovery Manager cannot protect a virtual machine unless it has valid inventory mappings. However, configuring site-wide inventory mappings is not mandatory for array-based replication protection groups, Virtual Volumes protection groups, and vSphere Replication protection groups. If you create an array-based replication protection group, a Virtual Volumes protection group, or a vSphere Replication protection group without having defined site-wide inventory mappings, you can configure each virtual machine in the group individually. You can override site-wide inventory mappings by configuring the protection of the virtual machines in a protection group. You can also create site-wide inventory mappings after you create a protection group, and then apply those site-wide mappings to that protection group.

Because placeholder virtual machines do not support NICs, you cannot change the network configurations of placeholder virtual machines. You can only change the network for a placeholder virtual machine in the inventory mappings. If no mapping for a network exists, you can specify a network when you configure protection for an individual virtual machine. Changes that you make to the placeholder virtual machine override the settings that you establish when you configure the protection of the virtual machine. Site Recovery Manager preserves these changes at the recovery site during the test and recovery.