Replication Using the HotAdd Method

HotAdd replication for Amazon provides faster performance than replication using the import method. By using an access node (VSA proxy) that is running on an Amazon instance, the replication operation can write directly to Elastic Block Storage (EBS) and inject Amazon drivers that are required for destination instances.

Requirements for HotAdd Replication

• The access node for the replication operation must be an Amazon EC2 instance in the destination region. A single access node can perform recovery operations for all Amazon availability zones within a region.

• For replication from VMware to Amazon, you can use an access node that runs on Windows or Linux. If you use an access node that runs on Linux, for both Windows and Linux guest VMs, the drivers must be installed on the source before performing the replication.

Requirements for Replication Operations when Amazon is the Destination

For Windows guest VMs, you can copy drivers that are required for AWS instances to the access node that is used for replication. During the replication, drivers are automatically installed on the destination guest instances.

For Linux guest VMs, you must copy the required drivers to the source VMs and then perform a new replication.

• For Windows VMs: Commvault attempts to copy required drivers automatically for replication to AWS instances, but automatic downloads might fail if a firewall is in place. If that occurs, you can copy required drivers to the access node that is used for the operation, and then retry the operation.

  On the access node, create an Amazon folder under the software_install_path/Commvault/ContentStore folder, and extract the contents of the following zip files in the Amazon folder:

  • https://s3.amazonaws.com/ec2-downloads-windows/Drivers/AWSPVDriverSetup.zip

  • https://s3.amazonaws.com/ec2-downloads-windows/EC2Config/EC2Install.zip

    

  Extract the following files to separate subfolders under the Amazon folder:

  • https://s3.amazonaws.com/ec2-windows-drivers-downloads/NVMe/Latest/AWSNVMe.zip

    

  • https://s3.amazonaws.com/ec2-windows-drivers-downloads/ENA/Latest/AwsEnaNetworkDriver.zip

    

• Make the following changes to source VMs before performing the replication:

  • When performing replication for an Active Directory domain controller, upgrade PV drivers as described in Upgrade a Domain Controller (AWS PV Upgrade).

  • Windows source VMs:

    • Install .NET 4.5 or a more recent version of .NET.

    • Enable Remote Desktop Protocol (RDP).

    • Disable Windows Firewall.

    • Disable User Account Control (UAC) in the Windows Control Panel.

    • Ensure that there is a minimum of 2 GB free space on the C: drive.

    • Verify that the Windows AutoAdminLogon feature is not disabled on the source VM, so that AWS drivers can be installed on the destination VM during replication.

    • HotAdd replication is not supported if the boot OS for the source VM uses GUID Partition Table (GPT) partitioning. Use the import method instead.

    • If the Windows security banner is enabled on the source VM, install the following components so that the replicated instances can pass instance status checks:

      https://s3.amazonaws.com/ec2-downloads-windows/Drivers/AWSPVDriverSetup.zip

      https://s3.amazonaws.com/ec2-downloads-windows/EC2Config/EC2Install.zip

    • To replicate source VMs that run on a version of Windows Server earlier than Windows Server 2012 R2, when the Windows AutoAdminLogon feature is disabled or when a firewall is in place in the environment, install drivers on source VMs before performing the replication, as described in Installing Drivers Manually for HotAdd Replication.

  • Linux source VMs:

    • Enable Secure Shell (SSH) for remote access.

    • The host firewall (such as Linux iptables) must permit access to SSH.

    • Ensure that Xen drivers are installed on the VM:

      xen-blkfront

      xen-netfront

      Installing Xen drivers on Linux guest VMs before replicating the VMs enables the required drivers to be in place when the Amazon instances are created, so that the Amazon instance can be started and users can access the instance.

    • To enable replication to Nitro instances, install NVMe and ENA drivers on source VMs or instances as described in the following pages (depending on the operating systems for the source VMs or instances):

      Amazon EBS and NVMe on Linux Instances

      How do I install and enable the latest ENA driver for Enhanced Network Support on an Amazon EC2 instance running Red Hat 6/7?

    • Ensure that Linux VMs use GRUB (GRUB legacy) or GRUB 2 as the bootloader.

    • Linux VMs must use one of the following for the root file system: ext2, ext3, ext4, Btrfs, JFS, or XFS.

    • Linux VM /etc/fstab entries should use UUIDs instead of device names, because device names might change during replication.

HotAdd Replication Process

Windows:

1. Create empty EBS volumes.

2. Attach EBS volumes to access node.

   Up to 21 volumes can be attached to the access node during replication, occupying device slots xvdf - xvdz.

3. Restore data to EBS volumes.

   A snapshot of the EBS volumes is taken and retained as an integrity snapshot for reference during the next incremental replication.

4. Inject AWS components and drivers.

5. Detach volumes from the access node.

6. Create the Amazon instance from the EBS volumes.

7. Automatically log on to the instance to install PV drivers and EC2 configuration service.

Linux:

1. Create empty EBS volumes.

   Up to 40 volumes can be attached to the access node during replication, occupying device slots xvdf - xvdz, or if the slots start with xvd, then xvdba - xvdbz, or a combination of both.

2. Attach EBS volumes to access node.

3. Restore data to EBS volumes.

   A snapshot of the EBS volumes is taken and retained as an integrity snapshot for reference during the next incremental replication.

4. Detach volumes from the access node.

5. Create the Amazon instance from the EBS volumes.