HotAdd transport mode is a VMware feature which provides an efficient method of passing virtual disk data between a VM and the proxy for the VMware node, as no data needs traverse the LAN.
The iSCSI HotAdd Transport mode will be used to backup/restore virtual disks only when:
- The VMware node’s proxy is a virtual machine that resides on the Datastore containing the VMDKs for the Virtual disks/machines to be backed up/restored and the proxy should be a member of the same Datacenter as the VM to be backed up.
- HotAdd transport also works with VMs stored on NFS partitions.
- The VM uses SCSI disks. HotAdd is not supported for backup or restore of IDE disks.
- HotAdd will not be used if the VMFS block size of the datastore containing the proxy’s virtual machine folder is not the same as the VMFS block size of the folder containing the folder of the VM to be backed up or restored.
- The proxy must be able to connect to TCP/IP port 902 on ESX/ESXi hosts while performing HotAdd backups or restores.