On a sunny day (Thu, 27 Feb 2020 09:16:00 -0000 (UTC)) it happened Martin
Gregorie  wrote in :

>On Thu, 27 Feb 2020 05:38:28 +0000, Jan Panteltje wrote:
>
>> The first is an image of the complete card made on an other PC (rp4 off,
>> card in other PC)
>> the other two are the tar -zcvf of both partitions of that card,
>>
>Good move, but you'll get faster backups and less SSD wear, if you're
>backing up to SD cards or SSDs, if you do it with either rsync or
>rsnapshot.
>
>I use both: rsnapshot for my overnight backup (I used to use compressed
>tar beckups and this brought the backup time down from 3 hours to 8
>minutes AND the backup can be accessed without needing to uncompress/untar
>anything) and rsync for my weekly backup to the set of disks kept offline
>in a firesafe.
>
>> Easy to unzip one and get any file back.
>> It is some more work and needs a reboot, but as I modifiy so much
>> 're-install' or 'update' is not in my books.
>> Practically every image is a new system.

True

For years I have followed the 3 methods backup system
1) SDcard FLASH
2) normal harddisk (few TB is very cheap) magnetic
3) Blu-ray optical.
I stopped with optical for now as I have about 1000 DVDs and blue-rays
in a big alu lightproof box, mostly movies though, box is full!
Seems magnetic medium still wins.
Have not tried any SSD yet, not sure about the reliability of that stuff,
price is high too.
Any practical experiences?
I must say optical when in constant climate and absolute dark still works here
after 20 years...
And then I have some on M-DISC, should last forever but size is only 4.7 GB..
good
for unique movies  and music.
A 32 GB card image should go on a blu-ray.


>No need to unzip if you use rsnapshot or rsync, so recovery is faster:
>just find the file(s) by looking through the directory structure and copy
>them back.

Indeed with all that harddisk size zip/unzip is not always needed, using md5sum
etc is good,
I run verify after making any backup, for that I use dvdimagecmp that I wrote
many years ago:
 http://panteltje.com/panteltje/dvd/dvdimagecmp-0.3.tgz
diff also works, but this gives more detail.

And keep a database of all you have!
For example disk 998 (box holds 1000, was almost last year)

998
Tue Oct  8 12:43:07 CEST 2019
BD-R25GB
Mediarange 4x inkjet printable
LG BH10LS38
Make sure you habve enough disk space.
dd if=/dev/zero bs=100000000 count=242 > bluray.iso
mke2fs  bluray.iso
mount -o loop=/dev/loop0 bluray.iso  /mnt/loop
cp stuff /mnt/loop/
du /mnt/loop
umount /mnt/loop
growisofs -speed=4 -dvd-compat -Z /dev/dvd=bluray.iso
dvdimagecmp -a bluray.iso -b /dev/dvd
# df
/dev/loop0       23261268  21022524    1057104  96% /mnt/loop
# l/mnt/loop/
total 20977548
-rw-r--r-- 1 root root      19095 May  7 23:33 xinutop_manual.txt
-rw-r--r-- 1 root root 4385000000 Jul  1 18:01 freibeuter_des_todes_german.ts  
            amovie
-rw-r--r-- 1 root root         58 Jul 11 10:40 xinutop-nav-x86-2.4.img.md5
-rw-r--r-- 1 root root  682624000 Jul 11 10:44 xinutop-nav-x86-2.4.img
-rw-r--r-- 1 root root 4294705152 Sep  8 01:51
stones_havana_NPO_3-20190907213907-.mts      amovie
-rw-r--r-- 1 root root  627385344 Sep  8 02:28
stones_havana_NPO_3-20190907213907-.mts1     amovie
-rw-r--r-- 1 root root 3949971456 Sep  8 05:59
stones_havana_NPO_3-20190907235958-.mts      amovie
-rw-r--r-- 1 root root 1993500000 Sep 24 16:53 the_great_wall_2016.ts          
            amovie
-rw-r--r-- 1 root root 2354400000 Oct  3 17:05 last_man_standing_1996.ts       
            amovie
-rw-r--r-- 1 root root 3172370000 Oct  8 12:39
a_cure_for_wellness_2016__german.ts          amovie

1000 entries like this, in a simple textfile
use
 dvd-list.txt | grep amovie
to list all movies
and it seems I have more than UK TV seems to have... endless repeats there...

283 movies....
LOL

cat dvd-list.txt | grep .img

Who needs a databeast?
locate cat grep is all ye need!

Sorry got carried away maybe have to buy an extra box for a thousand discs :-)

--- SoupGate-Win32 v1.05