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Permalink Reply by Mark Thacker on March 19, 2013 at 1:32pm

Hi Bill,

Glad to know that you are trying vmPRO.

Can you tell us a bit more about what you are experiencing? For example, what does the vmPRO GUI report for Smart Read, or Disk Savings? What is your target device and what protocol are you using to write data to the device (CIFS or NFS)? Are you backing up from a vCenter server or directly attached to an ESX server? What type of VM's are you backing up (i.e. what OS's and underlying file systems)? Are you using Change Block Tracking? What versions of VMware are you using?

vmPRO actually has a patented technology to reduce the amount of disk information read thus reducing the amount of information stored on disk and sent over the wire. When used with a Quantum DXi target, vmPRO will even provide sparse writing of data to a NFS share - meaning that blank data is simply skipped rather than being sent over the wire.

Most customers report a great reduction in the amount of disk IO and actual file sizes on disk of backups. Hence my long list of questions above.

Thanks.

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Permalink Reply by Bill Bajcz on March 19, 2013 at 1:57pm

Hi Mark,

The hosts are VMware 5.x esentials.  There are 2 hosts and PRO is connected directly to each host (I had difficulties with the Vcenter appliance.)  Guests are a mix of CentOS, Win2008, Win2003 SCO Unix and the PRO appliance.  The backup target is a simple linux-based network storage unit from Synology America.  The target is currently CIFS (windoze SMB) although the unit also supports NFS. 

I am uploading a copy of the latest report to hopefully answer the remaining questions.

BTW, I plan to present the results of my VM backup testing at a technical meeting of the iXorg group in May.

Thanks again for the swift response.

Attachments:

• __10.10.42.124_api_download_report_format=html.pdf, 85 KB

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Permalink Reply by DoubleDensity on March 20, 2013 at 7:49pm

vmPRO on its own will not deduplicate or compress the backup files, so if the target storage is not deduplicating there is the chance the backup flat files can accumulate rapidly depending on the provisioned size of the source VM disks. You could consider running a DXi V1000 as the target in order to provide that functionality, but here are some additional ideas you can try.

In your storage configuration on vmPRO referring to the CIFS share on the Synology, try changing the 'device' setting from 'generic' to 'Quantum DXi'. The main thing that changes when you switch that setting is that the Quantum DXi mode for CIFS enables the creation of sparse files -- in generic mode in order to ensure maximum compatibility sparse writing is disabled:

Even when sparse writing is active it can be tricky to get an accurate reading sometimes of how many bytes are actually being used by a VMDK disk in the underlying filesystem; for example in the case of sending sparse VMDKs to a Windows CIFS share it is difficult to see the true size because both Explorer and dir will report the NTFS logical size. We can use the Sysinternals 'du' command to show us the true size on disk:

You can download that tool here:

http://technet.microsoft.com/en-us/sysinternals/bb896651.aspx 

Another option you can try is to turn on CBT for the VMs you are backing up -- this will enable a differential backup rotation schedule for those VMs. The default when CBT is enabled is that it will perform one full backup a week followed by six days of differentials, but the rotation can be extended to a monthly period by adjusting the 'CBT Reset Schedule' parameters in the Folder settings area:

The CBT differential VMDKs will generally be much smaller than the fulls and may help you to store more recovery points on the target. 

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