Most SBC backup tools I have seen are based on rsync and they operate then on/with Ext4 filesystem. Is fine when you don't have complex servers and databases running. I am not sure about pihole, but I saw that by default it keeps a 1 year history so a database file of about 1GB. I am not sure what happens to integrity of such a file on the target if during copy/rsync the source file also changes. AFAIK databases have their ways to handle it, when power-loss or so, but not sure. If you want to be sure, use Btrfs as filesystem, then you can make atomic snapshots and use those for source of rsync or use: btrfs send -p <old snapshotnumber> <snapshot number>| ssh <remote_host> btrfs receive <backup folder>. That is the basic manual option. Complete tool is btrbk, it is standard in Debian repo, see https://digint.ch/btrbk/index.html docs of author. You still need some partition and bootloader handling I think. Or assume that a total crash is rare so only backup to NAS or so and reconstruct manually if you need a new SD-card or so or want to copy thing so eMMC of the OPi3.

It's not that I won't share it - I was waiting for some instruction of what information was needed. It looks like this... [ 15.261345] Internal error: Oops: 00000000960000004 [#1] SMP and what other information can I give that would help diagnose my trouble? After a restart, as the login prompt arrives - this comes on the screen and I can't seem get past it, other than powering the machine down and restarting it. Thank you for your help. Jon Dowd

Maybe this helps? https://forum.armbian.com/topic/29427-shrink-backup-a-tool-for-backing-up-sbcs/

Which you won't share since we all have second sights, right? Also code { font-family: Consolas,"courier new"; color: crimson; background-color: rgba(0, 0, 0, 0.2); padding: 2px; font-size: 105%; } armbianmonitor -u can be helpful. I have an Opi5 with nvme here and reboot works fine.