Re: n00b questions about using dar for archiving wikis [apologies]

thanks. i'll read the man page, but it will take me a while (it's long).

it looks as though i'll be doing a differential backup, but we'll see.
if i can't backup one file to a backup at a time, then i'll have to
invest in more storage, which will take some time to save up for.

On Sat, 24 Jul 2021 at 03:33, Denis Corbin <[email protected]> wrote:
>
> On 23/07/2021 08:43, griffin tucker wrote:
> > i didn't mean to upset you, i don't want you to do any development
> > unnecessarily.
>
> no worries, I just had not time to answer you, having a quite busy week
> at work, sorry for that.
>
> In brief, if you want to add new files to an already existing and
> completed backup, you cannot do that with dar (you can with tar but have
> to disable several other features, like compression and multi-volume
> AFAIR). With dar, you rather make a differential backup, or another full
> backup and convert the previous full backup to a decremental one.
>
> There is no plan to have such feature with dar as it would ruin the rule
> followed by dar to never modify an existing backup, but create a new one
> beside the old ones (while repairing, merging, and other operations)
> leaving the decision to the user to remove *or not* the old backup
> keeping them, for example, as secondary backups.
>
> As explained in a previous email, the binary delta feature (that makes a
> rsync like increment) is not available with decremental backup today.
> Without this feature, when a file's data changes the whole file is saved
> again (and is eventually compressed in the backup depending on your
> choice). Technically having binary delta with decremental could be
> possible, but so far the need did not seemed very strong for that.
>
>
> If you don't know whether dar is the tool that matches you need, check
> the documentation like the tutorial, it's always better to validate by
> yourself as you know better than anyone here the goal you tend to address.
>
> tutorial: http://dar.linux.free.fr/doc/Tutorial.html
>
> Feel free to ask if you have any particular question on how works or how
> to use any particular dar/libdar feature.
>
> Cheers,
> Denis
>