VCB / Legato / Compression

[ZMkenzie]

In our datacenter we are currently using VCB and Legato to do a weekly full backup of production machines (the backup is disk based, for disaster recovery).

Since legato disk backup is licensed per terabyte we'd like to use its native compression directives (+compressasm) to reduce space used (we can't use compressed folders because this won't affect the total space calculated by Legato).

But, when we try to add compressasm to our client properties (using "+compressasm: *.vmdk" or standard "NT with compression" directive) the backup job stops working. On the VCB side all seems to go as expected, the image is copied correctly on local disks, but then, all hangs and Legato waits forever for the process to finish.

Does anybody have experience on this area? I know i could launch a gzip script using "post" jobs on the VCB side, but i'd like to use Legato to compress data if possible because it will be a more cleaner solution.

Tnx in advance.

[kix1979]

I don't think it can compress over the wire. VCB writes the VMDK files to local disk, and then you could compress it. Legato may be confused since it is trying to compress while the file is being written, which it cannot do. The way we get around that with our tool, esxRanger, is that we have to actually intercept the data that VCB streams and then redirect it via our own process. I would think that Legato would need to do something similar to get the compressasm to work.

[ZMkenzie]

Legato doesn't need to compress data over the wire. VCB extracts data from esx servers and copy it on the VCB server, AFTER that, legato (with its agent on the VCB server) takes the exported folder and copy it on its Disk Backup device.

So, it shouldn't be a big problem if i use the +compressasm directive, for this reason i suppose there is a bug or something in VCB which prevents this to work correctly.

Probably i should open a bug report for this.

[kix1979]

Definitely sounds like a bug.