Re: extract fatal error

Hi,

On 23/08/2021 17:50, griffin tucker wrote:
> i'm trying to make incremental backups with delta sig in a script
> 
> first full backup runs fine:
> 
> dar --create "../${1}-${dd}-full" --delta sig --compression=gzip:5
> --hash=sha512 --slice=2G
> 
> then the incremental backup seems to run fine:
> 
> dar --create "${1}-${dd}-incr" --ref="${dar_prev_name}" --delta sig
> --hash=sha512 --slice=2G --compression=gzip:5 --quiet --fs-root
> "./${dd}/"
> 
> with no errors reported
> 
> however, after testing the extraction of the archive:
> 
> dar --extract "${1}-${dd}-incr" --ref="${dar_prev_name}" --fs-root
> "${dd}/temp-${1}-${dd}-incr/"
> 
> i get:
> 
> FATAL error, aborting operation: The archive and the isolated
> catalogue do not correspond to the same data, they are thus
> incompatible between them
> 
> what am i doing wrong?
> 
> 

The reason is that you do not need to provide the --ref option when
extracting a backup, unless the argument given to --ref is an isolated
catalogue creeated from the backup provided to the --extract argument
*and* you want to use this isolated catalogue as rescue of internal
catalogue of the archive you want to extract data from (if for example
the backup is corrupted near its end, where is located the internal
catalogue).

In brief: just remove --ref="${dar_prev_name}"

Note that restoring an incremental backup is expected to be done right
after the backup of reference it has been using, thus in your case, you
should do something more or less like this:

mkdir "${somewhere}"
dar --extract "../${1}-${dd}-full" --fs-root "${somewhere}"
dar --extract ""${1}-${dd}-incr" --fs-root "${somewhere}" -w

add -w (or -r) if you are OK to overwrite files by a more recent
versions saved in the incremental backup (else dar asks permission to do
so for each file...).

Cheers,
Denis