Protecting Virtual Machines to a Recovery Site vCenter Server

Priority – Determine the priority for transferring data from the protected site to the recovery site when there is limited bandwidth and more than one VPG is defined on the protected site. When there are updates to virtual machines protected in VPGs with different priorities, first the updates from the VPG with the highest priority are passed over the WAN. Medium priority VPGs will only be able to use whatever bandwidth is left after the high priority VPGs have used it. This is also true between medium and low priorities. Note that updates to the protected virtual machines are always sent across the WAN before synchronization data, such as during a bitmap or delta sync. During a synchronization, only after updates to the virtual machines are sent over the WAN, based on the VPG priority, is synchronization data from the VPG sent, and the synchronization data from the VPG with the highest priority is passed over the WAN before data from medium and low priority VPGs.

Zerto Virtual Replication uses the SCSI protocol. Only virtual machines with disks that support this protocol can be specified.

When virtual machines in a VPG are started in the recovery site, by default these machines are not started up in a particular order. If you want specific virtual machines to start before other machines, you can specify a boot order. The virtual machines are defined in groups and the boot order applies to the groups and not to individual virtual machines in the groups. You can specify a delay between groups during startup.

Initially, virtual machines in the VPG are displayed together under the Default group. If you want specific machines to start before other virtual machines, define new groups with one or more virtual machines in each group.

b) To change the name of a group, click the Pencil icon next to the group. To delete a group, click the delete icon on the right side. You cannot delete the Default group nor a group that contains a virtual machine.

e) Optionally, in Boot Delay, specify a time delay between starting up the virtual machines in the group and starting up the virtual machines in the next group. For example, assume three groups, Default, Server, and Client, defined in this order. The boot delay defined for the Default group is 10, for the Server group is 100, and for the Client group 0. The virtual machines in the Default group are started together and after 10 seconds the virtual machines in the Server group are started. After 100 seconds the virtual machines in the Client group are started.

Note: If the protected site is paired with only one recovery site, the recovery step is displayed with the Recovery Site field automatically filled in and defaults set for the SLA and Advanced settings, as shown below.

Recovery Site – The site to which you want to recover the virtual machines. After specifying the recovery site, other fields are displayed including the host and datastore to use for replication.

ZORG – If the site is defined in Zerto Cloud Manager, you specify the name the cloud service provider uses to identify you as a Zerto Organization, ZORG. For details about Zerto Cloud Manager, refer to Zerto Cloud Manager Administration Guide.

Host – The default cluster, resource pool or host in the recovery site that handles the replicated data. If the site is defined in Zerto Cloud Manager, only a resource pool can be specified and the resource pool must also have been specified as a resource in Zerto Cloud Manager¹. For details about Zerto Cloud Manager, refer to Zerto Cloud Manager Administration Guide.

When a resource pool is specified, Zerto Virtual Replication checks that the resource pool capacity is enough for any virtual machines specified in the VPG.

All resource pool checks are made at the level of the VPG and do not take into account multiple VPGs using the same resource pool. If the resource pool CPU resources are specified as unlimited, the actual limit is inherited from the parent but if this inherited value is too small, failover, move, and failover test operations can fail, even without a warning alert being issued by Zerto Virtual Manager.

Note that if a resource pool is specified and DRS is disabled for the site later on, all the resource pools are removed by VMware and recovery will be to any one of the hosts in the recovery site with a VRA installed on it.

Datastore – The default datastore to use for recovered virtual machine files and for their data volumes. Every datastore for the selected recovery host is included in the drop-down list. If a cluster or resource pool is selected for the host, only datastores that are accessible by every host in the cluster or resource pool are displayed.

Service Profile – The name of the service profile to use which determines the VPG SLA settings for the group, which apply to every virtual machine in the group. To change the VPG SLA settings, select the Custom Service Profile.

8. If the VPG SLA settings are editable, when the Zerto Cloud Manager is not used or when a Custom service profile is available, specify these settings for the group, which apply to every virtual machine in the group.

Journal History – The time that all write commands are saved in the journal. The longer the information is saved in the journal, the more space is required for each journal in the VPG. You can select the number of hours from 1 to 24 or the number of days from 2 to 14.

For additional journal-related fields, click ADVANCED.

Default Journal Datastore – The datastore used for the journal data for each virtual machine in the VPG. Select a datastore accessible to the host. When you select a specific journal datastore, the journals for each virtual machine in the VPG are stored in this datastore, regardless of where the recovery datastores are for each virtual machine. In this case, all protected virtual machines must be recovered to the hosts that can access the specified journal datastore.

Journal Size Hard Limit – The maximum size that the journal can grow, either as a percentage or a fixed amount. The minimum journal size, set by Zerto Virtual Replication, is 8GB. The journal is always thin-provisioned.

Journal Size Warning Threshold – The size of the journal that triggers a warning that the journal is nearing its hard limit.

Both the value of Size and Percentage must be less than the configured hard limit so that the warning will be generated when needed. In addition to the warning threshold, Zerto Virtual Replication will issue a message when the free space available for the journal is almost full.

Target RPO Alert – The maximum desired time between each automatic checkpoint write to the journal before an alert is issued. To increase the value, move the slider right; to decrease the value, move the slider left.

Test Reminder – The time recommended between testing the integrity of the VPG. A warning is issued if a test is not done within this time frame.

Enable WAN Traffic Compression – Whether or not data is compressed before being transferred to the recovery site. Compressing the data is more efficient but results in a small performance degradation. Enable WAN traffic compression if network considerations are more critical than CPU usage considerations. When WAN compression is enabled, the compressed data is written in compressed format to the recovery site journal. Even if WAN compression is selected, Zerto Virtual Replication decreases the level of compression if it takes too many resources. The VRA automatically adjusts the compression level according to CPU usage, including totally disabling it if needed. Zerto recommends enabling WAN compression. Zerto Virtual Replication can also work with third-party WAN optimization and acceleration technologies, such as those supplied by Riverbed Technologies and Silver Peak. When third-party WAN optimization is implemented, Zerto recommends disabling VPG WAN compression.

In this dialog, you can edit the values of one or more of the virtual machines in the VPG.

11. If you want to edit information in one field, click the field and update the information. If you want to edit information for several virtual machines at the same time, select the virtual machines and click EDIT SELECTED.

Recovery Host – The cluster, resource pool, or host that will host the recovered virtual machine. If the site is defined in Zerto Cloud Manager, only a resource pool can be specified and the resource pool must also have been defined in Zerto Cloud Manager. For details about Zerto Cloud Manager, see Zerto Cloud Manager Administration Guide.

When a resource pool is specified, Zerto Virtual Replication checks that the resource pool capacity is enough for all the virtual machines specified in the VPG.

If a resource pool is specified and DRS is disabled for the site later on, all the resource pools are removed by VMware and recovery is to any one of the hosts in the recovery site with a VRA installed on it.

All resource pool checks are made at the level of the VPG and do not take into account multiple VPGs using the same resource pool. If the resource pool CPU resources are defined as unlimited, the actual limit is inherited from the parent but if this inherited value is too small, failover, move, and failover test operations can fail, even without a warning alert being issued by Zerto Virtual Manager.

Recovery Datastore – The datastore where the VMware metadata files for the virtual machine are stored, such as the vmx file. If a cluster or resource pool is selected for the host, only datastores that are accessible by every ESX/ESXi host in the cluster or resource pool are displayed. This is also the datastore where RDM backing files for recovery volumes are located.

Journal Size Warning Threshold – The size of the journal that triggers a warning that the journal is nearing its hard limit.

Journal Datastore – The datastore used for the journal data for each virtual machine in the VPG. To change the default, specify a host and then select one of the datastores accessible by this host to be used as the journal datastore. When you select specific journal datastore, the journals for each virtual machine in the VPG are stored in this datastore, regardless of where the recovery datastores are for each virtual machine. In this case, all the protected virtual machines must be recovered to hosts that can access the specified journal datastore.

The STORAGE step is displayed. By default the storage used for the virtual machine definition is also used for the virtual machine data. For each virtual machine in the VPG, Zerto Virtual Replication displays its storage-related information.

Note: Steps that do not require input are marked with a check mark. You can jump directly to a step that has been marked with a check mark to edit the values for that step. Every step must be marked with a check mark before you can click DONE to create the VPG.

Thin – If the recovery volumes are thin-provisioned or not.

Swap – If the virtual machine to be replicated includes a swap disk as part of its configuration, mark the recovery disk for this disk as a swap disk. In this case, data is not replicated to the swap disk after initial synchronization.

Datastore – A new volume is used for replicated data. Specify the datastore to use to create disks for the replicated data. If the source disk is thin provisioned, the default for the recovery volume is that it is also thin provisioned.

The datastore specified for replication must have at least the same amount of space as the protected volume and an additional amount for the journal. The amount of additional space needed for the journal can be fixed by specifying a maximum size for the journal, or can be calculated as the average change rate for the virtual machines in the VPG, multiplied by the length of time specified for the journal history.

Zerto Virtual Replication supports the SCSI protocol. Only disks that support this protocol can be specified.

Raw Disk – The VMware RDM (Raw Device Mapping) to use for the replication: By default, RDM is recovered as thin-provisioned VMDK in the datastore specified in the VM Recovery Datastore field in the Edit VM dialog, and not to RDM.

Only a raw disk with the same size as the protected disk can be selected from the list of available raw disks. Other raw disks with different sizes are not available for selection. The RDM is always stored in the recovery datastore used for the virtual machine. The following limitations apply to protecting RDM disks:

You cannot define an RDM disk to be protected to a cloud service provider via a Zerto Cloud Connector nor if the virtual machine uses a BusLogic SCSI controller, nor when protecting or recovering virtual machines in an environment running vCenter Server 5.x with ESX/ESXi version 4.1 hosts.

Preseeded volume – Whether to copy the protected data to a virtual disk in the recovery site. Zerto recommends using this option particularly for large disks so that the initial synchronization will be faster since a Delta Sync can be used to synchronize any changes written to the recovery site after the creation of the preseeded disk. When not using a preseeded disk, the initial synchronization phase must copy the whole disk over the WAN. When using a preseeded virtual disk, you select the datastore and exact location, folder, and name of the preseeded disk, which cannot be an IDE disk. Zerto Virtual Replication takes ownership of the preseeded disk, moving it from its source folder to the folder used by the VRA. Only disks with the same size as the protected disk can be selected when browsing for a preseeded disk. The datastore where the preseeded disk is placed is also used as the recovery datastore for the replicated data.

If the preseeded disk is greater than 1TB on NFS storage, the VPG creation might fail. This is a known VMware problem when the NFS client does not wait for sufficient time for the NFS storage array to initialize the virtual disk after the RPC parameter of the NFS client times out. The timeout default value is 10 seconds. See the VMware documentation, http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1027919, which describes the configuration option to tune the RPC timeout parameter using the esxcfg-advcfg -s <Timeout> /NFS/SetAttrRPCTimeout command.

Datastore – The datastore where the preseeded disk is located.

Path – The full path to the preseeded disk.

■ If the VPG is being defined for a Zerto Organization, ZORG, the location of the preseeded disk must be defined in the Zerto Cloud Manager. For details, see Zerto Cloud Manager Administration Guide.

Swap disk – If the virtual machine to be replicated includes a swap disk as part of its configuration, mark the recovery disk for this disk as a swap disk. In this case, data is not replicated to the swap disk after initial synchronization.

Thin provisioning – If the recovery volumes are thin-provisioned or not. If the source disk is thin provisioned, the default for the recovery volume is that it is also thin provisioned.

The RECOVERY step is displayed. Recovery details include the networks to use for failover, move, and for testing failover, and whether scripts should run as part of the recovery operation.

Failover/Move Network – The network to use during a failover or move operation in which the recovered virtual machines will run.

Failover Test Network – The network to use when testing the failover of virtual machines in the recovery site. Zerto recommends using a fenced-out network so as not to impact the production network at this site.

Recovery Folder – The folder to which the virtual machines are recovered.

In this dialog, you can edit the values of one or more of the virtual machines in the VPG.

22. If you want to edit information in a field, click the field and update the information. If you want to edit information for several virtual machines at the same time, select the virtual machines and click EDIT SELECTED.

Recovery Folder – The folder to which the virtual machine is recovered.

Pre-recovery Script – The information about a script that should run at the beginning of the recovery process.

Post-recovery Script – The information about a script that should run at the end of the recovery process.

For both types of scripts, enter the following information:

Text Box	Description
Command to run	The full path of the script. The script must be located on the same machine as the Zerto Virtual Manager for the recovery site.
Params	The parameters to pass to the script. Separate parameters with a space.
Timeout	The time-out, in seconds, for the script to run. If the script runs before executing a failover, move, or test failover, and the script fails or the timeout value is reached, an alert is generated and the failover, move, or test failover is not performed. If the script runs after executing a failover, move, or test failover, and the timeout value is reached, an alert is generated. The default time-out value is specified in Performance and Throttling tab in the Site Settings dialog.

27. If you want to edit information in one field, click the field and update the information. If you want to edit information for several virtual machines at the same time, select the virtual machines and click EDIT SELECTED. Otherwise, go to step 30.

28. Specify the network details to use for the recovered virtual machines after a failover or move operation, in the Failover/Move column, and for the recovered virtual machines when testing replication, in the Test column.

In each column, specify the following:

Network: The network to use for this virtual machine.

Create New MAC Address: Whether the Media Access Control address (MAC address) used on the protected site should be replicated on the recovery site. The default is to use the same MAC address on both sites. Note that if you check this option, to create a new MAC address, and the current IP address is not specified, the protected virtual machine static IP address might not be used for the recovered virtual machine.

Change vNIC IP Configuration: Whether or not to keep the default virtual NIC (vNIC) IP configuration. The vNIC IP is only changed after recovery for virtual machines with VMware Tools running.

Refer to the Zerto Virtual Replication Interoperability Matrix for the list of operating systems for which Zerto supports Re-IPing.

To change the vNIC IP, select Yes in the Failover/Move or Test column. If you select to use a static IP connection, set the IP address, subnet mask, and default gateway. Optionally, change the preferred and alternate DNS server IPs and the DNS suffix. If you leave the DNS server and suffix entries empty, or select to use DHCP, the IP configuration and DNS server configurations are assigned automatically, to match the protected virtual machine. You can change the DNS suffix.

If the virtual machine has multiple NICs but is configured to only have a single default gateway, fill in a 0 for each octet in the Default gateway field for the NICs with no default gateway.

During a failover, move, or test failover, if the recovered virtual machine is assigned a different IP than the original IP, after the virtual machine has started it is automatically rebooted so that it starts up with the correct IP. If the same network is used for both production and test failovers, Zerto recommends changing the IP address for the virtual machines started for the test, so that there is no IP clash between the test machines and the production machines.

Copy to failover test – Copies the settings in the Failover/Move column to the Test column.

Copy to failover/move – Copies the settings in the Test column to the Failover/Move column.

The BACKUP step is displayed. Backup properties govern the VPG backup, including the repository where the backups are saved. Backup extends the ability to recover virtual machines in a VPG going back one year.

Target Repository – The name of the repository where the offsite backups are written. Repositories are configured via the SETUP tab as described in Setting Up Offsite Backups.

Retention Period – The length of time to keep offsite backups, up to a maximum of one year. For details of how this affects the number of backups saved, see Offsite Backups.

Run Job Every – The day and time to start the backup.

Retries – Whether to rerun the backup job automatically if the job fails. If you select this option, you must also define the number of retries that will be attempted and the time to wait after a job fails before running the backup job again.

Post-Backup Script – The information about a script that should run at the end of the recovery process. Enter the following information:

Text Box	Description
Command to run	The full path of the script. The script must be located on the same machine as the Zerto Virtual Manager for the recovery site.
Parameters	The values of parameters to pass to the script. Separate parameters with a space.
Timeout	The time-out, in seconds, for the script to run. If the timeout value is reached, an alert is generated. The default time-out value is specified in the Performance and Throttling tab of the Site Settings dialog.