[Discuss] lvm snapshot cloning

[markw at mohawksoft.com (markw at mohawksoft.com)]

> markw at mohawksoft.com wrote:
>> Suppose you have a 1TB hard disk. How on earth do you back that up?
>> Think now if you want to pipe that up to the cloud for off-site backup.
>>
>> The snapshot device "knows"
>> what is different. You don't have to really backup 1TB every time, you
>> only have to backup the changes to it since the last full backup.
>
> If you are at the point of considering developing software to do this,
> instead of just using off-the-shelf solutions, then you should consider
> using inotify[1]. I believe using this library you could log to a
> database the inodes that have been altered over a given period of time,
> which another tool could then use to package up the data and send it to
> your local or remote backup server.

That's for a file level backup which has been done to death.
>
> Of course without snapshots you'd needs to take other steps to insure
> consistency, if that matters for your application.
>
> Seems DRBD[2] would be another way to address this, though not practical
> for a remote backup server, as it'll send every change to the remote
> server in real time.
>
> Generally though, it seems like you are trying to re-invent ZFS, which
> does both the snapshotting you want, as we'll as communicating
> differential changes to a remote server. But I understand your
> objections to ZFS.
>
> 1. https://github.com/rvoicilas/inotify-tools/wiki/
> 2. http://www.drbd.org/
>
>
>> I can't give too much away...
>
> Why? Developing something you plan to patent? Turn into a commercial
> product and you want to keep the technology a trade secrete?

Potentially.
>
> If those don't apply, then why not detail your scheme? Better to idea
> vetted before you've invested a lot of time into building it.

Well, lets just say I'm doing three things....

I'm doing some research for my current employer's product.
I'm thinking about creating an open source tool kit for managing a
category of resources.
Lastly, a "pro" version ($$$) of fore mentioned tool it.

I have to be careful in that I do not overlap my current employer (I have
NO intention to do so, but there is technology overlap, so I'm very
sensitive in how I phrase things.)

>
>  -Tom
>
> --
> Tom Metro
> Venture Logic, Newton, MA, USA
> "Enterprise solutions through open source."
> Professional Profile: http://tmetro.venturelogic.com/
>