I recently had the opportunity to implement VMware vCenter Site Recovery Manager (SRM) in three different environments using two different replication technologies (vSphere and Array-based Replication). The setup and configuration of the SRM software is pretty much straightforward. The differences come into play when deciding on what the best replication option is for your business needs.
vSphere Replication is built into SRM 5.0 and is included no matter what replication technology you decide to use. With vSphere Replication, you do not need to have costly identical storage arrays at both your sites, because the replication is managed through vCenter. With the ability to manage though vCenter, you are given more flexibility in regard to which VMs are protected. VMs can be protected individually, as opposed to doing so at the VMFS datastore. vSphere Replication is deployed and managed by virtual appliances installed at both sites. Replication is then handled by the ESXi hosts, with the assistance of the virtual appliances. vSphere Replication supports RPOs as low as 15 minutes.[framed_box] vSphere Replication Benefits:
- No need for costly storage arrays at both sites
- More flexibility in choosing which VMs are protected (can do so individually)
The two Array-based Replication technologies that I implemented were EMC MirrorView and EMC Symmetrix. Both of these tie into SRM using a storage replication adapter (SRA). The SRA is a program that is provided by the array vendor that allows SRM access to the array. Configuration of replication is done outside of vCenter at the array level. Unlike vSphere Replication, Array-based Replication requires you to protect an entire VMFS datastore or LUN, as opposed to individual VMs. One of the biggest benefits of Array-based Replication is its ability to provide automated re-protection of the VMs and near-zero RPOs.[framed_box] vSphere Replication Benefits:
- Automated re-protection of VMs
- Near-zero RPOs
VMware vCenter Site Recovery Manger gives you disaster recovery management that is highly sought after in today’s market, allowing you to perform planned migrations, failover and failback, automated failback and non-disruptive testing.
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