Re: [Duplicity-talk] Enabling compression in a middle of a primary chain

[edgar . soldin]

had a quick look at the sources 
https://gitlab.com/duplicity/duplicity/-/blob/main/duplicity/file_naming.py#L184-203
 and encryption takes priority over compression. the option already is not 
doing anything. it is meant to be used like `--no-encryption --no-compression` 
so you will end up with plain tar volumes.

so as long as your backup repo ends up with '.gpg' files, which it totally should then 
you should be able en/disable/change gpg compression to your liking already. as said 
"should", we are talking backup meaning safety meaning thorough testing :)

good luck ..ede/duply.net

On 14.01.2023 15:59, Nathan MALO via Duplicity-talk wrote:
> It's the following :
> /usr/bin/duplicity --no-compression --log-file /path/to/logfile.log --archive-dir 
> /path/to/archive_folder --volsize 10240 --tempdir /path/to/temp_dir --encrypt-key 
> encrypt_key_fp --sign-key sign_key_fp --full-if-older-than 1M 
> /path/to/folder_to_backup 'multi:///path/to/multi/backend/filecat 
> .json?mode=mirror&onfail=abort
>
> and I've disabled compression in my gpg.conf with compress-algo set to none.
>
> Nate
>
> Le sam. 14 janv. 2023 à 15:57, edgar.soldin--- via Duplicity-talk 
> <duplicity-talk@nongnu.org <mailto:duplicity-talk@nongnu.org>> a écrit :
>
>     btw. reads like gpg does compress by default anyway
>     https://superuser.com/questions/427264/does-gnu-gpg-compress-by-default 
> <https://superuser.com/questions/427264/does-gnu-gpg-compress-by-default>
>
>     ..ede/duply.net <http://duply.net>
>
>     On 14.01.2023 15:46, Nathan MALO via Duplicity-talk wrote:
>      > Hello Ede,
>      >
>      > Thanks for your quick reply.
>      > I should have mentioned that I use --no-compression on the duplicity 
> command-line.
>      > So I do not know at which step this argument intervene.
>      >
>      > Thank you,
>      >
>      > Nate
>      >
>      > Le sam. 14 janv. 2023 à 15:41, edgar.soldin--- via Duplicity-talk <duplicity-talk@nongnu.org 
> <mailto:duplicity-talk@nongnu.org> <mailto:duplicity-talk@nongnu.org 
> <mailto:duplicity-talk@nongnu.org>>> a écrit :
>      >
>      >     hey Nate,
>      >
>      >     On 14.01.2023 15:26, Nathan MALO via Duplicity-talk wrote:
>      >      > Hello,
>      >      >
>      >      > My backup strategy consists of making a master every 30days and 
> then making incremental backups between masters.
>      >      >
>      >      > I also have a multi backend : local disk and ftp with different 
> retention policy.
>      >      >
>      >      > Currently the ftp backend has one primary chain and two secondary 
> ones. The local disk has one primary chain. The next master will be made in about 
> three weeks.
>      >      >
>      >      > I have always done my backups uncompressed encrypted.
>      >      >
>      >      > Will there be any issue if I enable compression in the middle of 
> the primary chain, or should I wait for the new master to be created ?
>      >
>      >     assuming you are talking about enabling compression in gpg via 
> `--gpg-options` i would assume that this wouldn't be an issue. afaik gpg will 
> silently detect the used compression or not and decrypt.
>      >
>      >     regardless, i would advise you to do a local test. backup a small test data 
> set gpg encrypted to a file:// target, do a full, some incrementals, add e.g. 
> `--gpg-options="--compress-algo=bzip2 --bzip2-compress-level=9"`, do some more 
> incrementals.
>      >     not try to restore/verify each of these, just to make sure the 
> switch didn't break anything.
>      >
>      >     good luck.. ede/duply.net <http://duply.net> <http://duply.net 
> <http://duply.net>>
>      >
>      >     _______________________________________________
>      >     Duplicity-talk mailing list
>      > Duplicity-talk@nongnu.org <mailto:Duplicity-talk@nongnu.org> 
> <mailto:Duplicity-talk@nongnu.org <mailto:Duplicity-talk@nongnu.org>>
>      > https://lists.nongnu.org/mailman/listinfo/duplicity-talk 
> <https://lists.nongnu.org/mailman/listinfo/duplicity-talk> 
> <https://lists.nongnu.org/mailman/listinfo/duplicity-talk 
> <https://lists.nongnu.org/mailman/listinfo/duplicity-talk>>
>      >
>      >
>      > _______________________________________________
>      > Duplicity-talk mailing list
>      > Duplicity-talk@nongnu.org <mailto:Duplicity-talk@nongnu.org>
>      > https://lists.nongnu.org/mailman/listinfo/duplicity-talk 
> <https://lists.nongnu.org/mailman/listinfo/duplicity-talk>
>
>
>     _______________________________________________
>     Duplicity-talk mailing list
>     Duplicity-talk@nongnu.org <mailto:Duplicity-talk@nongnu.org>
>     https://lists.nongnu.org/mailman/listinfo/duplicity-talk 
> <https://lists.nongnu.org/mailman/listinfo/duplicity-talk>
>
>
> _______________________________________________
> Duplicity-talk mailing list
> Duplicity-talk@nongnu.org
> https://lists.nongnu.org/mailman/listinfo/duplicity-talk