Installing Virtual Replication Appliances

The Zerto installation includes the OVF template for Virtual Replication Appliances (VRAs). A VRA is a Zerto virtual machine that manages the replication of virtual machines across sites. A VRA must be installed on every host that manages virtual machines that require protecting in the protected site and on every host that manages virtual machines in the recovery site. The VRA compresses the data that is passed across the WAN from the protected site to the recovery site. The VRA automatically adjusts the compression level according to CPU usage, including totally disabling it if needed.

A VRA can manage a maximum of 1500 volumes, whether these volumes are being protected or recovered.

The VRA is a custom, very thin, Linux-based virtual machine with a small footprint, disk – memory and CPU – and increased security since there are a minimum number of services installed.

Zerto recommends installing a VRA on every hypervisor host so that if protected virtual machines are moved from one host in the cluster to another host in the cluster there is always a VRA to protect the moved virtual machines.

VRA Installation Requirements

To install a VRA you require the following on the host:

15GB storage space
At least 1GB of reserved memory.
(vSphere only) The ESX/ESXi version must be in accordance with supported ESX/ESXi versions in the Interoperability Matrix, and Ports 22 and 443 must be enabled on the host during the installation.
Port 8100 must be enabled on SCVMM.
(Hyper-V only) Minimum PowerShell version: 4.0
The following PowerShell cmdlet has been run:

Install-WindowsFeature –Name Hyper-V -IncludeManagementTools -Restart

Before You Begin:

You must know the following information to install a VRA:

(vSphere only) If the ESXi version is 5.5 or higher and the VRA should connect to the host with user credentials, or if the ESXi version is lower than 5.5, the password to access the host root account.
Note: For ESXi versions 5.5 or higher, by default the VRA connects to the host with a vSphere Installation Bundle, VIB. Therefore, it is not necessary to enter the password used to access the host root account.
The storage the VRA will use, and the local network used by the host.
The network settings to access the peer site; either the default gateway or the IP address, subnet mask, and gateway.
Note: When the gateway is not required, you can specify 0.0.0.0 as the gateway, for example when performing self replication.
If a static IP is used, instead of DHCP, which is the Zerto recommendation, you need to know the IP address, subnet mask, and default gateway to be used by the VRA.

Note: In a non-production environment it is often convenient to use DHCP to allocate an IP to the VRA. In a production environment this is not recommended. For example, if the DHCP server changes the IP allocation on a reboot, the VRA does not handle the change.

If the peer site VRAs are not on the default gateway, you must set up routing to enable the VRAs on this site to communicate with the peer site VRAs before defining the VRAs.
Setting up routing after defining VRAs only applies to VRAs installed after the routing is set.
Any existing VRA is not affected and access to these VRAs continues via the default gateway.
If the default gateway stops being used, you must reinstall the VRAs that were installed before setting up paired site routing.
(vSphere only) For the duration of the installation of the VRA, the Zerto Virtual Manager enables SSH in the vCenter Server.
(vSphere only) You must know the following information to install a VRA:
The password to access the host root account, for ESXi 5.x.
The datastore the VRA will use and the local network used by the host.
The network settings to access the peer site; either the default gateway or the IP address, subnet mask, and gateway.
If a static IP is used, instead of DHCP, which is the Zerto recommendation, you need to know the IP address, subnet mask, and default gateway to be used by the VRA.

Note: In a non-production environment it is often convenient to use DHCP to allocate an IP to the VRA. In a production environment this is not recommended. For example, if the DHCP server changes the IP allocation on a reboot, the VRA does not handle the change.

If the peer site VRAs are not on the same network as the peer site Zerto Virtual Manager, you must set up routing to enable the Zerto Virtual Manager to communicate with the peer site VRAs, as described in the Zerto Virtual Manager Administration Guide for the VMware vSphere Environment.

To install Zerto Virtual Replication Appliances (VRAs) on ESX/ESXi hosts:

1. In the Zerto User Interface, click SETUP > VRAs.
2. Select a host which requires a VRA and click NEW VRA.

The Configure and Install VRA dialog is displayed. The dialog displayed depends on the ESX/i version:

ESXi versions from 5.5 ESXi versions before version 5.5

The Configure and Install VRA dialog is displayed. The dialog displayed depends on the ESX/i version:

ESXi versions from 5.5 ESXi versions before version 5.5
Note: If you selected a cluster or multiple hosts, the VRA is installed on the first host in the displayed list.
3. Specify the following in the Host Details section:

Host: The host on which the VRA is installed. The drop-down displays the hosts that do not have a VRA installed, with the selected host displayed by default.

From ESXi 5.5, by default, Zerto Virtual Manager uses a vSphere Installation Bundle, VIB, to connect to the host. When using VIB:

The user does not enter a password.
Once a day, Zerto Virtual Manager checks that the VRA and host can connect. If the connection fails, Zerto Virtual Manager re-initiates the connection automatically and logs it.

For ESX/i versions earlier than 5.5, when using a password, root access is required. Once a day, Zerto Virtual Manager checks that the password is valid. If the password was changed, an alert is issued, requesting the user enter the new password.

Use credentials to connect to host: When unchecked, the Zerto Virtual Manager uses VIB to connect to the host. This field is only relevant for ESXi 5.5 and later.

Host Root Password: When the VRA should connect to the host with a password, check Use credential to connect to host and enter the root user password used to access the host. When the box on the right side is checked, the password is displayed in plain text. This field is only relevant for ESXi 5.x hosts.

Datastore: The datastore that contains the OS disks of the VRA VM. You can install more than one VRA on the same datastore.

Network: The network used to access the VRA.

4. Leave the VRA RAM and VRA Group values with their defaults.
5. Specify the following in the VRA Network Details section:

Configuration: Specify DHCP.

Note: In a production environment the Static option is the recommended option.
6. Click INSTALL.

The VRA installation starts and the status is displayed in the TASKS popup dialog in the status bar and under MONITORING > TASKS.

The VRA displayed name and DNS name is Z-VRA-hostname. If a virtual machine with this name exists, for example when a previous VRA was not deleted, the VRA name has a number appended to it.

Add a VRA to every host that hosts virtual machines that you want replicated. Zerto recommends installing a VRA on every listed host. An alert is issued after the first VRA is installed in a cluster that tells you to install a VRA on the other hosts in the cluster. The alert is automatically removed when all the hosts in the cluster have VRAs installed.

Note: VRAs are configured and managed by the Zerto Virtual Manager. You cannot take snapshots of VRAs as snapshots cause operational problems for the VRAs.