On 05/04/2010 09:29 AM, Kyle McDonald wrote:
> On 3/2/2010 10:15 AM, Kjetil Torgrim Homme wrote:
>> "valrh...@gmail.com" <valrh...@gmail.com> writes:
>>
>>   
>>> I have been using DVDs for small backups here and there for a decade
>>> now, and have a huge pile of several hundred. They have a lot of
>>> overlapping content, so I was thinking of feeding the entire stack
>>> into some sort of DVD autoloader, which would just read each disk, and
>>> write its contents to a ZFS filesystem with dedup enabled. [...] That
>>> would allow me to consolidate a few hundred CDs and DVDs onto probably
>>> a terabyte or so, which could then be kept conveniently on a hard
>>> drive and archived to tape.
>>>     
>> it would be inconvenient to make a dedup copy on harddisk or tape, you
>> could only do it as a ZFS filesystem or ZFS send stream.  it's better to
>> use a generic tool like hardlink(1), and just delete files afterwards
>> with
>>
>>   
> There is a perl script floating around on the internet for years that
> will convert copies of files on the same FS to hardlinks (sorry I don't
> have the name handy). So you don't need ZFS. Once this is done you can
> even recreate an ISO and burn it back to DVD (possibly merging hundreds
> of CD's into one DVD (or BD!). The script can also delete the
> duplicates, but there isn't much control over which one it keeps - for
> backupsyou may realyl want to  keep the earliest (or latest?) backup the
> file appeared in.

I've used "Dirvish" http://www.dirvish.org/ and rsync to do just
that...worked great!

Scott

> 
> Using ZFS Dedup is an interesting way of doing this. However archiving
> the result may be hard. If you use different datasets (FS's) for each
> backup, can you only send 1 dataset at a time (since you can only
> snapshot on a dataset level? Won't that 'undo' the deduping?
>  
> If you instead put all the backups on on data set, then the snapshot can
> theoretically contain the dedpued data. I'm not clear on whether
> 'send'ing it will preserve the deduping or not - or if it's up to the
> receiving dataset to recognize matching blocks? If the dedup is in the
> stream, then you may be able to write the stream to a DVD or BD.
> 
> Still if you save enough space so that you can add the required level of
> redundancy, you could just leave it on disk and chuck the DVD's. Not
> sure I'd do that, but it might let me put the media in the basement,
> instead of the closet, or on the desk next to me.
> 
>   -Kyle
> 
> 
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss@opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

Reply via email to