Re: rsync --delete vs rsync --delete-after

From	Michael Kjörling <2695bd53d63c@ewoof.net>
Newsgroups	linux.debian.user
Subject	Re: rsync --delete vs rsync --delete-after
Date	2024-01-18 12:10 +0100
Message-ID	<HXyrw-3UbG-1@gated-at.bofh.it> (permalink)
References	<HXgXD-3Jzs-5@gated-at.bofh.it> <HXhTH-3K8d-5@gated-at.bofh.it> <HXpod-3OBu-1@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On 17 Jan 2024 20:23 -0500, from hunguponcontent@gmail.com (Default User):
> BTW, the two backup drives are external 4 Gb USB HDDs.  The secondary
> backup drive is always kept away from the computer, in a locked steel
> box, except when it is attached to the computer to have the primary
> backup drive copied to it. 
> 
> The primary backup drive is almost always attached to the computer, so
> that I can access files archived there, that are not on the computer.
> Probably not good practice, but that's why I have the secondary backup
> drive.

Hold on. Let's pause right here.

**That "primary backup drive" is not a backup at all.**

If at any point it can legitimately contain the only copy of a file
that you want to keep, then conceptually it is not a backup.

If it is continuously accessible from the system that you're trying to
protect, then anything bad which happens to that system is liable to
also at least potentially affect your "primary backup drive" as well.

There is nothing wrong with using external storage media to expand the
storage capacity of your computer, but you really shouldn't treat or
consider it as being a backup, because a backup is a _second_ copy to
be used if the primary copy somehow becomes unusable, corrupt,
inaccessible or whatever else might be the case.

Solve the right problem.


> I guess in the back of my mind I was thinking of a scenario where a
> file on the primary backup drive might be corrupted or deleted before
> being copied to the secondary backup drive.  Then if it is not present
> on the primary backup drive, rsync dutifully deletes it from the
> secondary backup drive. If the file is no longer on the computer's
> internal SSD, I am then SOL.

That is why a backup scheme should include some form of retention;
ideally immutable. A single botched backup run should not risk the
integrity of an only backup.


> BTW(2), I do use rsnapshot with cron jobs to back up the internal SSD
> to the primary backup drive daily (and weekly, monthly, yearly).  But I
> am not sure if I could also use it to do copies of the primary backup
> drive to the secondary backup drive (maybe using an additional
> configuration file)? 

You can use rsnapshot with any number of different configuration
files. Just pass `-c` to it to name the configuration file other than
the default. (For a long time I had two, and a script selecting either
one based on the backup target drive in use for that particular
backup. Worked great.)


> As for ZFS . . .   I wish!  But I think the resource requirements would
> be too high for my setup, so it probably would be impractical - or
> impossible.  And  then there's the complexity.  And the learning curve.

ZFS works fine on low-spec'd systems. I use it on a VPS with 2 GB RAM
without any problems. You really want 64-bit, but that's about it.

And while ZFS _can_ be complex, and supports rather complex usage
scenarios (because it is, at its core, an enterprise solution), at the
basic level the biggest difference is that you write "zpool create"
instead of "mkfs.ext4".

-- 
Michael Kjörling                     🔗 https://michael.kjorling.se
“Remember when, on the Internet, nobody cared that you were a dog?”

Thread

rsync --delete vs rsync --delete-after Default User <hunguponcontent@gmail.com> - 2024-01-17 17:30 +0100
  Re: rsync --delete vs rsync --delete-after David Christensen <dpchrist@holgerdanske.com> - 2024-01-17 18:30 +0100
    Re: rsync --delete vs rsync --delete-after Keith Bainbridgge <keithrbaugroups@gmail.com> - 2024-01-18 00:10 +0100
    Re: rsync --delete vs rsync --delete-after Default User <hunguponcontent@gmail.com> - 2024-01-18 02:30 +0100
      Re: rsync --delete vs rsync --delete-after David Christensen <dpchrist@holgerdanske.com> - 2024-01-18 08:40 +0100
      Re: rsync --delete vs rsync --delete-after Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-18 12:10 +0100
        Re: rsync --delete vs rsync --delete-after <tomas@tuxteam.de> - 2024-01-18 12:20 +0100
          Re: rsync --delete vs rsync --delete-after Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-18 12:50 +0100
      Re: rsync --delete vs rsync --delete-after Michel Verdier <mv524@free.fr> - 2024-01-18 14:00 +0100
  Re: rsync --delete vs rsync --delete-after Kushal Kumaran <kushal@locationd.net> - 2024-01-17 19:30 +0100
    Re: rsync --delete vs rsync --delete-after Default User <hunguponcontent@gmail.com> - 2024-01-17 21:00 +0100
      Re: rsync --delete vs rsync --delete-after Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-17 21:20 +0100
      Re: rsync --delete vs rsync --delete-after Andy Smith <andy@strugglers.net> - 2024-01-17 22:00 +0100
      Re: rsync --delete vs rsync --delete-after Michel Verdier <mv524@free.fr> - 2024-01-18 02:40 +0100
      Re: rsync --delete vs rsync --delete-after hw <hw@adminart.net> - 2024-01-18 12:20 +0100
        Re: rsync --delete vs rsync --delete-after Ralph Aichinger <ra@h5.or.at> - 2024-01-18 13:50 +0100
          Re: rsync --delete vs rsync --delete-after Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-18 14:10 +0100
            Re: rsync --delete vs rsync --delete-after Ralph Aichinger <ra@h5.or.at> - 2024-01-18 15:30 +0100
            Re: rsync --delete vs rsync --delete-after hw <hw@adminart.net> - 2024-01-26 16:40 +0100
              Re: rsync --delete vs rsync --delete-after Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-26 17:30 +0100
                Re: rsync --delete vs rsync --delete-after hw <hw@adminart.net> - 2024-01-28 18:00 +0100
          Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Andy Smith <andy@strugglers.net> - 2024-01-26 16:20 +0100
            Re: Home UPS recommendations (Was Re: rsync --delete vs rsync --delete-after) fxkl47BF@protonmail.com - 2024-01-26 16:30 +0100
            Re: Home UPS recommendations Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-26 16:40 +0100
              Re: Home UPS recommendations Tixy <tixy@yxit.co.uk> - 2024-01-26 17:20 +0100
              Re: Home UPS recommendations "James H. H. Lampert" <jamesl@touchtonecorp.com> - 2024-01-26 17:20 +0100
            Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Roger Price <debian@rogerprice.org> - 2024-01-26 19:10 +0100
              Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) David Wright <deblis@lionunicorn.co.uk> - 2024-01-26 20:50 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Roger Price <debian@rogerprice.org> - 2024-01-27 11:00 +0100
            Re: Home UPS recommendations Felix Miata <mrmazda@earthlink.net> - 2024-01-26 20:10 +0100
              Re: Home UPS recommendations ghe2001 <ghe2001@protonmail.com> - 2024-01-26 20:30 +0100
                Re: Home UPS recommendations debian-user@howorth.org.uk - 2024-01-26 21:50 +0100
            Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) hw <hw@adminart.net> - 2024-01-28 19:00 +0100
              Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Andy Smith <andy@strugglers.net> - 2024-01-28 20:00 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs  rsync--delete-after) gene heskett <gheskett@shentel.net> - 2024-01-29 07:00 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Andy Smith <andy@strugglers.net> - 2024-02-08 16:30 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Charles Curley <charlescurley@charlescurley.com> - 2024-02-08 17:30 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Curt <curty@free.fr> - 2024-02-08 17:40 +0100
                Re: Home UPS recommendations Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-02-08 18:00 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) hw <hw@adminart.net> - 2024-02-09 12:10 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Dan Ritter <dsr@randomstring.org> - 2024-02-09 13:10 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) hw <hw@adminart.net> - 2024-02-09 22:40 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) Dan Ritter <dsr@randomstring.org> - 2024-02-09 23:30 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync --delete-after) "Roy J. Tellason, Sr." <roy@rtellason.com> - 2024-02-09 17:40 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync --delete-after) Stefan Monnier <monnier@iro.umontreal.ca> - 2024-02-09 18:20 +0100
                Re: Home UPS recommendations Felix Miata <mrmazda@earthlink.net> - 2024-02-10 01:10 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync  --delete-after) hw <hw@adminart.net> - 2024-02-09 22:50 +0100
                Re: Home UPS recommendations (Was Re: rsync --delete vs rsync --delete-after) "Roy J. Tellason, Sr." <roy@rtellason.com> - 2024-02-11 19:10 +0100
                Re: Home UPS recommendations Felix Miata <mrmazda@earthlink.net> - 2024-02-09 18:20 +0100
                Re: Home UPS recommendations debian-user@howorth.org.uk - 2024-02-09 21:40 +0100
                Re: Home UPS recommendations hw <hw@adminart.net> - 2024-02-09 22:50 +0100
                Re: Home UPS recommendations Felix Miata <mrmazda@earthlink.net> - 2024-02-10 01:00 +0100
                Re: Home UPS recommendations hw <hw@adminart.net> - 2024-02-10 03:20 +0100
                Re: Home UPS recommendations Felix Miata <mrmazda@earthlink.net> - 2024-02-10 04:30 +0100
                Re: Home UPS recommendations hw <hw@adminart.net> - 2024-02-10 11:10 +0100
                Re: Home UPS recommendations Felix Miata <mrmazda@earthlink.net> - 2024-02-10 15:00 +0100
                Re: Home UPS recommendations hw <hw@adminart.net> - 2024-02-10 16:50 +0100
                Re: Home UPS recommendations Joe <joe@jretrading.com> - 2024-02-10 19:50 +0100
                Re: Home UPS recommendations gene heskett <gheskett@shentel.net> - 2024-02-10 22:50 +0100
                Re: Home UPS recommendations hw <hw@adminart.net> - 2024-02-11 02:00 +0100
          Re: rsync --delete vs rsync --delete-after hw <hw@adminart.net> - 2024-01-26 16:20 +0100
            Re: Data and hardware protection measures; was: rsync --delete vs  rsync --delete-after Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-26 17:00 +0100
              Re: Data and hardware protection measures; was: rsync --delete vs  rsync --delete-after hw <hw@adminart.net> - 2024-01-28 19:30 +0100
                Re: Data and hardware protection measures Michael Kjörling <2695bd53d63c@ewoof.net> - 2024-01-28 20:30 +0100
                Re: Data and hardware protection measures Felix Miata <mrmazda@earthlink.net> - 2024-01-28 21:50 +0100
            Re: rsync --delete vs rsync --delete-after Ralph Aichinger <ra@h5.or.at> - 2024-01-27 14:10 +0100
  Re: rsync --delete vs rsync --delete-after Stefan Monnier <monnier@iro.umontreal.ca> - 2024-01-18 05:20 +0100
    Re: rsync --delete vs rsync --delete-after Andy Smith <andy@strugglers.net> - 2024-01-18 15:40 +0100
      Re: rsync --delete vs rsync --delete-after Stefan Monnier <monnier@iro.umontreal.ca> - 2024-01-18 16:10 +0100
      Re: rsync --delete vs rsync --delete-after Michel Verdier <mv524@free.fr> - 2024-01-18 22:10 +0100
        Re: rsync --delete vs rsync --delete-after Andy Smith <andy@strugglers.net> - 2024-01-18 22:50 +0100
          Re: rsync --delete vs rsync --delete-after Default User <hunguponcontent@gmail.com> - 2024-01-19 03:40 +0100
          Re: rsync --delete vs rsync --delete-after Michel Verdier <mv524@free.fr> - 2024-01-19 08:10 +0100

csiph-web