Groups > linux.debian.user > #220871

Re: how to keep 2 PCs partially in sync

From	Anastasios Lisgaras <tasosnumberten@yahoo.gr>
Newsgroups	linux.debian.user
Subject	Re: how to keep 2 PCs partially in sync
Date	2020-04-04 14:10 +0200
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On 3/25/20 11:07 AM, Andrei POPESCU wrote:
> If a file is corrupted, deleted, etc. in one place that will be
> propagated to all copies.
> 
> Depending on the features provided by the synchronisation tool they
> could be *a part* of a backup solution.
> 
> See http://taobackup.com for what a complete backup solution should
> provide.
> 
> Kind regards,
> Andrei
> 

Sorry, but again, I don't see the problem.
If I choose to delete a file from a machine - I will want the same for 
the rest of the machines. What's the problem with that?


On 3/25/20 12:49 PM, Dan Purgert wrote:
> I don't think he meant to imply using external-to-you "cloud" providers
> (gdrive, dropbox), but rather creating his own personal "cloud".
> 
> Be it something pretty -- Nextcloud, for example -- or something
> utilitarian (a central NFS or SSHFS server holding all the data).
> 
> I've used Nextcloud in these situations, it's actually pretty good with
> slower connections.  Since everything is a (machine-)local copy, in
> addition to being stored centrally; something I work on "here(tm)" gets
> updated "everywhere" shortly after I've saved the document.
> 
> I've only really ever run into problems with it when there was a
> godawful slow connection with a machine that'd been offline for 2 weeks
> while I was on vacation (and I forgot to spin it up at home before
> heading out)
>



I have also installed in the past the *Νextcloud* locally ( in a 
Raspberry Pi ) and it really worked amazingly! In fact, it worked so 
perfectly that, because of that I didn't deal with *Syncthing*.
In fact, I could not understand their differences.
Syncthing seems more restrictive than Nextcloud because it does not have 
the "cloud" (WEB UI) function offered by Nextcloud.
However, I would really like to try Syncthing to see what it really 
offers and to be able to compare it with Nextcloud.

What is your opinion?



On 3/25/20 7:44 PM, Linux-Fan wrote:
> Hello,
> 
> there have been multiple answers already, so forgive me if my post does not
> seem to add anything valuable. Still, it bugs me that there are many
> different solutions proposed without their advantages and disadvantages
> given?
> 
> I think that it is an important factor how the systems "online status" (in
> sense of power and networking) is to be considered? Are both systems online
> simultaneously? Are both systems online at the same time only for
> synchonization?
> 
> I can think of different solutions depending on what is actually
> wanted/neede:
> 
> * Cluster File Systems.
>    People have already mentioned ceph (which is more an object storage
>    and thus slow on small files IIRC?). I can add OCFS (Oracle Cluster
>    File System) to the list, although it is not so easy to set up.
>    Cluster file systems make sense if both systems are online at the same
>    time and should both access a common file system. Often, cluster
>    file systems want a "third" machine for doing the actual storage work
>    (e.g. an iSCISI target of OCFS). I have also tried out GFS2 in the past,
>    but it is a PITA to set up!
> 
> * Synchonization Tools.
>    There are tools to invoke explicitly to call the synchronization.
>    These make sense if both systems are online at the same time only
>    for synchronization... if not, one will need to deal with "both changed"
>    conflicts on a manual basis. I have no experience with syncthing
>    (mentioned in the thread) -- syncthing might have a solution for this...
> 
> * Network File Systems.
>    If you have a constellation of: system1 and system2 where
>    system2 online means system1 is online, too, then you might
>    install a "file server" (NFS or similar) on system1 and share
>    files through this mechanism. From all approaches proposed, I
>    would recommend this as being the least complex in operation
>    although this does not mean it is the least complex to setup.
> 
> * "Cloud"-like file synchronization.
>    These usually require a "third" server, too. And in my experience,
>    whenever one is using "synchronized" files for non-trivial data
>    processing (e.g. creating and reading a lot of files, storing a
>    database, accessing the data with many processes...) most of these
>    systems will fail one way or another (up to causing data loss). Yet,
>    most people using such systems do not seem to have these issues :)
>    These tools are useful in scenarios where there is no guarantee for
>    any machine being online the same time as the other although this is
>    achieved at the cost of running a "third" machine 24/7...
> 
> HTH and YMMV
> Linux-Fan


I really liked your *detailed* post! It really is a detailed and 
comprehensive answer.

In my use case, I have both a safe and a secure remote server machine 
(VM) and a raspberry Pi at my home to run continuously & incessantly 24/7.
I have three computers. One at work a laptop and a desktop computer.
What I want is for the three computers to have specific directories and 
files shared/synchronized.
( Probably the whole /home directory of my user. )
I also want to be able to sometimes share/send my files - securely - to 
third parties.
What do you think is the best approach for me?
Maybe Syncthing + Nextcloud ?


Thank you.
Tasos

Thread

how to keep 2 PCs partially in sync Patrick Scribus <pythonic.tuchs@gmx.net> - 2020-03-24 22:10 +0100
  Re: how to keep 2 PCs partially in sync Brad Rogers <brad@fineby.me.uk> - 2020-03-24 22:40 +0100
  Re: how to keep 2 PCs partially in sync Brian Sammon <debian-user@brisammon.fastmail.fm> - 2020-03-24 22:50 +0100
  Re: how to keep 2 PCs partially in sync Andrei POPESCU <andreimpopescu@gmail.com> - 2020-03-24 23:20 +0100
    Re: how to keep 2 PCs partially in sync Peter Ehlert <peter@sdi-baja.com> - 2020-03-25 01:00 +0100
  Re: how to keep 2 PCs partially in sync deloptes <deloptes@gmail.com> - 2020-03-25 00:00 +0100
    Re: how to keep 2 PCs partially in sync Joe <joe@jretrading.com> - 2020-03-25 10:30 +0100
      Re: how to keep 2 PCs partially in sync Dan Purgert <dan@djph.net> - 2020-03-25 11:50 +0100
        Re: how to keep 2 PCs partially in sync deloptes <deloptes@gmail.com> - 2020-03-25 12:10 +0100
  Re: how to keep 2 PCs partially in sync David Christensen <dpchrist@holgerdanske.com> - 2020-03-25 00:10 +0100
  Re: how to keep 2 PCs partially in sync "der.hans" <deb-user@LuftHans.com> - 2020-03-25 00:20 +0100
  Re: how to keep 2 PCs partially in sync Mark Allums <mark@allums.email> - 2020-03-25 01:10 +0100
    Re: how to keep 2 PCs partially in sync Charles Curley <charlescurley@charlescurley.com> - 2020-03-25 06:40 +0100
      Re: how to keep 2 PCs partially in sync Anastasios Lisgaras <tasosnumberten@yahoo.gr> - 2020-03-25 09:00 +0100
        Re: how to keep 2 PCs partially in sync Andrei POPESCU <andreimpopescu@gmail.com> - 2020-03-25 10:10 +0100
          Re: how to keep 2 PCs partially in sync Charles Curley <charlescurley@charlescurley.com> - 2020-03-25 15:50 +0100
          Re: how to keep 2 PCs partially in sync Anastasios Lisgaras <tasosnumberten@yahoo.gr> - 2020-04-04 14:10 +0200
            Re: how to keep 2 PCs partially in sync Curt <curty@free.fr> - 2020-04-04 15:20 +0200
              Re: how to keep 2 PCs partially in sync <tomas@tuxteam.de> - 2020-04-04 17:00 +0200
                Re: how to keep 2 PCs partially in sync Leslie Rhorer <lesrhorer@att.net> - 2020-04-04 18:50 +0200
                Re: how to keep 2 PCs partially in sync Anastasios Lisgaras <tasosnumberten@yahoo.gr> - 2020-04-05 14:50 +0200
                Re: how to keep 2 PCs partially in sync Peter Ehlert <peter@sdi-baja.com> - 2020-04-05 16:10 +0200
                Re: how to keep 2 PCs partially in sync Anastasios Lisgaras <tasosnumberten@yahoo.gr> - 2020-04-05 22:20 +0200
                Re: how to keep 2 PCs partially in sync Peter Ehlert <peter@sdi-baja.com> - 2020-04-06 21:10 +0200
                Re: how to keep 2 PCs partially in sync Anastasios Lisgaras <tasosnumberten@yahoo.gr> - 2020-04-07 19:00 +0200
                Re: how to keep 2 PCs partially in sync Peter Ehlert <peter@sdi-baja.com> - 2020-04-07 22:40 +0200
                Re: how to keep 2 PCs partially in sync Charles Curley <charlescurley@charlescurley.com> - 2020-04-08 04:20 +0200
                Re: how to keep 2 PCs partially in sync Curt <curty@free.fr> - 2020-04-08 14:30 +0200
                Re: how to keep 2 PCs partially in sync Peter Ehlert <peter@sdi-baja.com> - 2020-04-08 17:30 +0200
            Re: how to keep 2 PCs partially in sync Andrei POPESCU <andreimpopescu@gmail.com> - 2020-04-04 18:00 +0200
            Re: how to keep 2 PCs partially in sync Andrei POPESCU <andreimpopescu@gmail.com> - 2020-04-04 18:10 +0200
            Re: how to keep 2 PCs partially in sync Linux-Fan <Ma_Sys.ma@web.de> - 2020-04-04 20:50 +0200
  Re: how to keep 2 PCs partially in sync Linux-Fan <Ma_Sys.ma@web.de> - 2020-03-25 18:50 +0100

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