Re: [gentoo-user] Backup questions

[Dale]

Marc Joliet wrote:
> Am Freitag, 10. August 2018, 04:46:17 CEST schrieb Dale:
>> Wols Lists wrote:
>>> On 08/08/18 04:43, Dale wrote:
>>>> Howdy,
>>>>
>>>> I just bought two external drive enclosures.  One is sort of a spare but
>>>> I do plan to do some backups on it, mostly pictures from my camera.  In
>>>> one of the enclosures I put a single 6TB drive that I found on ebay.  It
>>>> has about 7,000 hours on it so it should have some life left yet and it
>>>> passed the smartctl tests.  It is USB but it transfers fast.  Now to
>>>> some questions.  I use rsync.  Command looks something like rsync -auv
>>>> /source/ /destination/.  If I backup the config files in my home
>>>> directory, should I also include the --delete option?  If after a
>>>> upgrade for example a config file is deleted, because it is no longer
>>>> needed, or renamed, should the old file be removed or is there a reason
>>>> to keep them on the backups?  Adding the --delete option isn't a problem
>>>> command wise BUT I wonder if it can cause a problem at some point.
>>>> Thoughts on that.  I plan to use the --delete option for videos since if
>>>> I deleted one, it is likely broken or something.  Biggest question is
>>>> about config files.
>>> May I suggest using btrfs for your backup drive? One MAJOR caveat - DO
>>> NOT let the drive fill up - a combination of snapshots and drive-full
>>> has been known (quite often) to trash the file system. But provided you
>>> make sure it doesn't go above about 80% you should be fine.
>>>
>>> You can add an option to rsync such that it will back up "in place". In
>>> other words, if only 1K is changed in a 1M file, it will overwrite that
>>> 1K. So when you back up, the procedure is to take a snapshot, then run
>>> rsync with both "in place" and "delete".
>>>
>>> This will give you the space economy of incremental backups, combined
>>> with the utility of full backups - each snapshot is a full backup as of
>>> that date, but each new snapshot only increases disk usage by the
>>> changes since the last. And you reclaim space by deleting old snapshots.
>> I did think about btrfs.  I've read a lot of threads on here about
>> people using it and it seems to have come a long ways and be pretty
>> stable.  Right now, I've got a lot going on and really don't have the
>> time to sit down and read up on it and how it works or what all it can
>> do.  In all honesty, if my system were to crash later when I don't have
>> so much going on, I'd like to move to btrfs for as much as possible of
>> my system.
> Yeah, it's a good idea to wait until you have time :) .  And then migrate
> piecemeal, not all at once.  Following up on Wol's suggestion, I would start
> with the backup drive, since you can exploit most of the features there (well,
> snapshots and compression, at least).  Personally, I've had mostly good
> experience with btrfs and enjoy its send/receive feature for full-system
> incremental backups.
>
>> I suspect /boot would still have to be ext2 or something
>> because of grub.
> GRUB actually supports btrfs.  However, on a UEFI system you will need a FAT32
> file system for /boot, so I would argue that on a relatively recent system the
> issue is moot.
>


Yea, time is even more limited now.  My Mom is still in the hospital
about a hour away.  I'm not supposed to visit people there, and other
places where a lot of sick people can be, but it's my Mom.  I went
twice.  The morning after the second visit, I was at the Doctors
office.  Now I'm sick.  Luckily, the meds are working.  Thing is, I
don't feel like messing with computer stuff right now.  Even cooking a
meal is not so interesting.  I can't taste or smell anyway.  So, it may
be a while before I get the time to deal with any of this.  I would
likely not learn anything about a new file system even if I read it more
than once.  I'm even avoiding updates just to prevent anything from
going sideways.  I wonder, how many times will I proof and edit this
email???? 

I thought I read Grub, the new version, supported more file systems. 
Still, just for safety, I'd likely still use ext2.  There's a lot of new
stuff out there.  Just tons of options. 

Thanks.

Dale

:-)  :-)