Nextcloudpi - broken after crash; would need help and advice how to proceed

Hello to all!
I had a power outtage here;
seems it crashed my ncp instance completely which ran for several years now without any major problems.
Is anybody willing to give me advice and lead me step by step to - at least - try to recover the data?

Basic information:

NextCloudPi version  v1.50.3
OS                   Debian GNU/Linux 10. 4.4.202-1237-rockchip-ayufan-gfd4492386213 (aarch64)
automount            no
USB devices          none
datadir              /mnt/md0/nc-data (doesn't exist)
rootfs usage         3.7G/59G
swapfile             none
dbdir                /mnt/md0/nc-db
Nextcloud check      error
HTTPD service        up
PHP service          up
MariaDB service      down
Redis service        up
HPB service          down
Postfix service      up
Internet check       ok

There should be a raid1 with two 1TB hdds in the box (well the hdds are actually there :wink: ) for the data, but it seems this raid is not mounted. mariadb is down with a lot of errors; basically saying it cannot access the data. Which I suppose is connected to the raid not being mounted.

Anyway: if anyone could give me some hints or ask me to post some logs (also tells how to get them…) I’ll be greatfull for any ideas and suggestions.


Actually, investigating this issue further, showed that I lost my raid1 completely:

cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] 
unused devices: <none>

There should be listed two drives in Raid1.
So at the moment this is more a general linux question. If the raid comes back there probably will be the database files present.

Well, the solution was easier than I expected:
I only had to check the software raid to find out that one disk completely failed. This caused the other disk not showing up, also. Thanks to a suggestion from a friendly person on the Internet ;-), I rebooted the system with only one disk (the one that was ok), and everything was back and running.
Thank God, not only for that patient person, but for all data to be alive again.