6.5
Table Of Contents
- Using VMware vSphere Replication
- Contents
- About Using VMware vSphere Replication
- Replicating Virtual Machines
- How the Recovery Point Objective Affects Replication Scheduling
- How the 5 Minute Recovery Point Objective Works
- How Retention Policy Works
- Replicating a Virtual Machine and Enabling Multiple Point in Time Instances
- Using vSphere Replication with Virtual SAN Storage
- Using vSphere Replication with vSphere Storage DRS
- How vSphere Replication Synchronizes Data Between vCenter Server Sites During Initial Configuration
- Replicating Virtual Machines Using Replication Seeds
- Replicating a Virtual Machine in a Single vCenter Server Instance
- Best Practices For Using and Configuring vSphere Replication
- Configure Replication for a Single Virtual Machine to vCenter Server
- Configure Replication for Multiple Virtual Machines to vCenter Server
- Move a Replication to a New vSphere Replication Server
- Stop Replicating a Virtual Machine
- Reconfiguring Replications
- Reconfigure Recovery Point Objectives (RPO) in Replications
- Resize the Virtual Machine Disk Files of a Replication that Uses Replication Seeds
- Resize Virtual Machine Disk Files of a Replication that Does Not Use Replication Seeds
- Change the Point in Time Settings of a Replication
- Change the Target Datastore Location of a Replication
- Monitoring and Managing Replications in vSphere Replication
- Performing a Recovery with vSphere Replication
- Troubleshooting vSphere Replication
- Generate vSphere Replication Support Bundle
- vSphere Replication Events and Alarms
- Solutions for Common vSphere Replication Problems
- Error at vService Bindings When Deploying the vSphere Replication Appliance
- OVF Package is Invalid and Cannot be Deployed
- Connection Errors Between vSphere Replication and SQL Server Cannot be Resolved
- Application Quiescing Changes to File System Quiescing During vMotion to an Older Host
- Configuring Replication Fails for Virtual Machines with Two Disks on Different Datastores
- vSphere Replication Service Fails with Unresolved Host Error
- Scalability Problems when Replicating Many Virtual Machines with a Short RPO to a Shared VMFS Datastore on ESXi Server 5.0
- vSphere Replication Sites Appear in the Not Authenticated State
- Error Recovering Virtual Machine in a Single vCenter Server Instance
- vSphere Replication RPO Violations
- vSphere Replication Appliance Extension Cannot Be Deleted
- vSphere Replication Does Not Start After Moving the Host
- Unexpected vSphere Replication Failure Results in a Generic Error
- Reconnecting Sites Fails If One Of the vCenter Servers Has Changed Its IP Address
- Uploading a Valid Certificate to vSphere Replication Results in a Warning
- vSphere Replication Server Registration Takes Several Minutes
- Generating Support Bundles Disrupts vSphere Replication Recovery
- vSphere Replication Operations Take a Long Time to Complete
- vSphere Replication Operations Fail with Authentication Error
- vSphere Replication Does Not Display Incoming Replications When the Source Site is Inaccessible
- vSphere Replication is Inaccessible After Changing vCenter Server Certificate
- vSphere Replication Cannot Establish a Connection to the Hosts
- Anti-virus Agent in Firewall Terminates Virtual Machine Replication
- Initial Full Synchronization of Virtual Machine Files to VMware Virtual SAN Storage Is Slow
- Configuring Replication Fails Because Another Virtual Machine has the Same Instance UUID
- Not Active Replication Status of Virtual Machines
- vSphere Replication Operations Run Slowly as the Number of Replications Increases
- Error at Reconfiguring the vSphere Replication Management Server from the Virtual Appliance Management Interface
- Unable to Establish an SSH Connection to the vSphere Replication Appliance
- The Replication Pauses When You Add a New Disk To the Source VM
- The vSphere Replication Appliance Root File System Switches to Read-only Mode and Login Fails
If you enable multiple point-in-time (PIT) snapshots, you must make allowances for the additional
components that each snapshot creates in the Virtual SAN storage, based on the number of disks per
virtual machine, the size of the disks, the number of PIT snapshots to retain, and the number of failures to
tolerate. When retaining PIT snapshots and using Virtual SAN storage, you must calculate the number of
extra components that you require for each virtual machine:
Number of disks x number of PIT snapshots x number of mirror and witness components
Examples of using this formula demonstrate that retaining PIT snapshots rapidly increases the number of
components in the Virtual SAN storage for every virtual machine that you configure for
vSphere Replication:
n
You have a virtual machine with two 256 GB disks for which you retain 10 MPIT snapshots, and you
set the default Virtual SAN storage policy:
n
2 (number of disks) x 10 (number of PIT snapshots) x 3 (2 mirror components + 1 witness) = 60
components for this one virtual machine.
n
You have a virtual machine with two 512 GB disks for which you retain 10 PIT snapshots, and you set
the default Virtual SAN storage policy:
n
2 (number of disks) x 10 (number of PIT snapshots) x 5 (4 mirror components of 256 GB each + 1
witness) = 100 components for this one virtual machine.
The number of PIT snapshots that you retain can increase I/O latency on the Virtual SAN storage.
Using vSphere Replication with vSphere Storage DRS
vSphere Replication can operate with target sites that have VMware vSphere
®
Storage DRS™ enabled.
Storage DRS can detect the data that vSphere Replication copies on the target site and can move
replications without affecting the replication process.
How vSphere Replication Synchronizes Data Between
vCenter Server Sites During Initial Configuration
When you configure a virtual machine for replication, vSphere Replication starts an initial configuration
task during which a replica virtual machine is created on the target site, and data synchronization occurs
between the source and the target vCenter Server site.
The speed of data synchronization depends on the availability of information about block allocation of the
VMDK files. vSphere Replication uses this information to find empty regions of the disks and accelerate
the sync operations by skipping these regions. The speed of data synchronization also depends on the
site for which block allocation information is available.
n
If the allocation information is available at both sites, data synchronization occurs at the highest
possible speed.
n
If the allocation information is available only at the source or the target site, vSphere Replication skips
the empty regions on the VMDK disks at that site, but processes the entire disk at the site where
allocation information is not available. Therefore, data synchronization is slower.
Using VMware vSphere Replication
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