Virtual Appliance (HotAdd)
- HotAdd Mode is a LAN free data transfer mode. It attaches the virtual machine disk to the backup proxy. The backup proxy uses VADP (VMware vStorage API for Data Protection) for backup and replication from ESXi Servers.
- If your Vembu BDR backup server runs in a virtual machine, virtual disks will be HotAdded on the virtual machine. HotAdd mode will be selected only for virtual machines with SCSI disks. Vembu BDR backup server utilizes the VMware SCSI HotAdd and attached the disk to the a VM.
- The VM data will be written directly to the target datastore. When the backup or replication job finishes, the disks are unmounted from the backup proxy and the snapshots will be deleted.
- HotAdd mode works best when the proxy is a virtual machine and resides on the same datacenter as the VM to be backed up. This mode will improves your backup speed and reduces the overall load on the ESXi server.
We recommend you to deploy your configurations in such a way that the SAN mode will be selected when you trigger the backup job. In the absence of SAN, we recommend you to configure your settings such that the transport mode will be HotAdd.
Prerequisites -
- ESXi Server
- A VM in the same ESXi Server
- Backup Proxy must have the latest VMware Tools installed
Guidelines -
- The backup may fail if the virtual machine which is backed up does not have SCSI controller. This mode works only if the guest machine and backup proxy have SCSI hard disk.
- The backup may fail if VMware tools are not installed in the guest machine.
Working -
- The backup job is triggered from the Vembu BDR backup server and a initiation is sent to the Vembu backup proxy that the backup process is taking place. The backup proxy fetches the details of the VM as it is present in the same ESXi host.
- Vembu BDR backup server also sends an acknowledgment to the vSphere host to take a snapshot. The ESXi host fetches the details of the VM (VM Disk) and sends it to the backup proxy. The VM disks are then attached to the Vembu backup proxy.
- The Vembu BDR backup server will read the data from the backup proxy through the disks attached and sends it to the backup repository.
- Once the process is completed, the disks will be detached from Vembu backup proxy.
