We are having problems with performance when restoring from disk on backup exec 15. We're running an ESXI 5.1 cluster and several servers got hit with ransomeware. We are restoring our fileserver first from a datadomain (Current software 188.8.131.52-544198) target for backup to disk and when restoring it starts at 1468 MB/Minute restore and then drops down to somwehre between 40 and 68 MB per minute. We have over a terabyte to restore in all and cannot afford the extended time to restore.
We ensured that the network for restore and connection is set to 9000 MTU and rebooted but still unable to get better speed. Most searches either returns information for restores from tape or backup performance tuning. Until the ransomware, backups were working just fine with no known performance issues.
I found a NetBackup TechNote that seems to be relevant to any kind of backup software that is used, since the problem is with VMware:
* Due to a limitation in the APIs in VMware's Virtual Disk Development Kit (VDDK), the write performance during virtual machine restore does not use the maximum bandwidth of the underlying hardware and therefore may not match the read speed.
* VMware APIs cannot perform simultaneous writes to the same datastore from multiple restore jobs.
For better performance, do not run simultaneous restore jobs to the same datastore.