On 29/10/14 17:40, Dr. Boris Neubert wrote:
>
>
> Am 28. Oktober 2014 21:46:26 schrieb Adam Goryachev
> <mailinglists AT websitemanagers.com DOT au>:
>
>> On 29/10/14 07:00, xpac wrote:
>>> Currently I have BackupPC set to simply backup the entire directory which
>> contains the .vmsd, .vmx, .vmdk, etc files.
>>> Is there a "better"/recommended/best practices way to do this that is
>> different than what I am currently doing?
>> You could in theory take a snapshot of the LV that the disk image sits
>> on, mount the snapshot, then create the "chunks", and then umount/delete
>> the snapshot, or any similar method, though a restore will produce an
>> image of a "crashed" machine (like power failure crashed).
> That's what I do except for creating the chunks. The drawback about the
> large files is that the initial backup takes days to complete. In addition,
> I use the snapshot feature to be able to revert to previous version of the
> VM. I therefore keep only one full backup at all.
Actually, with large files and small (relatively small compared to the
size of the file) changes is that even an incremental backup can take a
very long time (again compared to the size of the changes).
I try not to keep snapshots, because they affect the performance of the
VM so significantly. backuppc pre backup sets up the snapshot, mounts
the VM disk, etc, then the backup is completed to backup the actual
files of the VM, and finally the post backup umounts and deletes the
snapshot.
Back to the images though, each day (not controlled by backuppc, just
scheduled), the image split/etc is done. I just use the unix split, and
also a small C program I wrote which simply slows down the IO (ie, I set
the number of bytes/sec of STDIN that is sent to STDOUT so that I don't
utilise all available disk IO and slow down all the running VM's), and
write to another directory. So yes, it uses up double the space of disk
capacity (but capacity is cheap, performance is expensive). Therefore
when backuppc runs, it will always see one set of the split files, and
these are mostly unchanged (even though the timestamp changes), that
just means rsync needs to read the full file on the backup client,
backuppc doesn't need to with checksum-cache, but since there is no
content changed, it is very quick. I can only suggest you test this
yourself to see the difference it can make on your systems, for me it
was significant.
In addition, I also copy those small split files to another remote
system for DR purposes, where there are multiple directories of the
small files. In a DR situation, I just need to cat all those files back
together, and then boot up the VM.
> I plan to refine this by additionally use BackupPc on certain virtual disks
> with user data.
I don't know what you mean by "use *backuppc on virtual disks* which
also contain user data" or if you mean "use backuppc to *backup virtual
disks with user data*"....
Hopefully the second :)
Regards,
Adam
--
Adam Goryachev Website Managers www.websitemanagers.com.au
------------------------------------------------------------------------------
_______________________________________________
BackupPC-users mailing list
BackupPC-users AT lists.sourceforge DOT net
List: https://lists.sourceforge.net/lists/listinfo/backuppc-users
Wiki: http://backuppc.wiki.sourceforge.net
Project: http://backuppc.sourceforge.net/
|
