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Backup Exec 21.4 Improves VM Backup Performance with Asynchronous Read


Fast backup and quick recovery are critical for any business nowadays. The amount of data in the world is growing at a staggering rate, and today we have less time than ever to protect it. System administrators are busy with many other tasks, making backup a significant factor in modern business environments.

Veritas Backup Exec provides unified data backup and recovery for small and midsize businesses. We deliver cost-effective, unified backup and recovery for all your data: across virtual, physical, and multi-cloud environments. Backup Exec will always give you comprehensive protection against external threats so that if the unthinkable happens, your critical data everywhere is backed up and ready for recovery quickly and easily.

Agent for VMware lets you backup and restore virtual machines that use VMware ESX/ESXi/vSphere/vCenter. A VMware Backup Host can access Virtual Machine data from datastores using four different methods – SAN, LAN(NBD), Hot Add, NBDSSL. These methods are referred to as VMware Transport modes. Generally, the Hot Add/SAN transport mode backups are faster as compared with NBD because, in this mode, the ESX/ESXi host reads data from storage and sends it across a network to the VMware backup host.

For more details on transport mode, see Veritas Support documents:

NBD (network block device) is the most universal VDDK transport mode. It does not require dedicated backup proxy VMs like Hot Add and works on all datastore types, not just SAN.

With the NFC (network file copy), NBD & NBD SSL backups performance improved. In vSphere 6.7 and later, asynchronous I/O for NBD transport mode is available. It can greatly enhance the data transfer speed of the NBD transport mode. Synchronous I/O requests are blocking calls, whereas asynchronous requests are not blocking calls. With BE 21.4, we will only use the asynchronous APIs for backup jobs if the setting is enabled and will not be used for restoring.

The user will choose to use the feature by making the changes in the UI while scheduling a backup job. The backup job will use synchronous read operation for the unsupported version.

During the internal testing for VMware Virtual Machines backup, we have observed significant performance improvement.

Enable async.pngIn the job log, we added a message which informs that the backup used async mode.



More details about the latest feature:

Try Backup Exec during a 60-day free trial here:

For more information, please refer to our or administrator’s guide.