Data loss after power failure

I am a new user of unRaid and as my girls (5 and 7) started playing Minecraft I found out about the MineOS docker.

It was set up and working perfectly (the Minecraft server was a home network one). The server and the docker did not have any issues with stopping and restarting. I also had an archive took just 2 days ago and set the MineOS configuration to auto-archive on a daily basis.

Today there were a couple of power failures and the system was not auto-starting, as I had set MineOS to automatically start but I had forgotten to do so for the Array (shares etc).

Upon returning home and verifying that everything was up and running properly, I found out that there is absolutely nothing on MinoOS WebUI (profiles / servers).

I am a Windows user but I played around a bit with telneting and/or browsing through a windows client in unRaid folders. Some of my actions may not be correct, but I doubt any harm was done.

/mnt/appdata/minecraftos/ is there, but the folders that matter (archive, profile, server) are empty.

The docker.img file (10GB on creation) has increased to 10.4GB during the past 5 days of operation (no other dockers installed by me).

As MineOS seems to be mounting specific contents from docker.img, I proceeded mounting the whole thing with mkdir /usr/minetest , mount -o loop docker.img minetest (or /usr/minetest , can’t recall right now).

I browsed through all folders, mostly looking in /var/games and /usr/games for something I could use / copy, but I can’t find anything. Most interesting things reside in /containers and in /btrfs. Also found the id of the MineOS docker in there but nothing interesting in its respective subfolders.

I hope you can help me, I really want to avoid disappointing the girls for losing their game in Minecraft. So…

Where can I look to get the data copied over again in the right location as to resume playing? I wouldn’t mind copying all related data (ie /server) to my PC, re-installing MineOS docker and copying it back over.

I can’t believe this could be due to data loss from the power failure. There is no problem with my HDDs or unRaid or the Array, and every other file is there. It 's weird that even the MineOS archive I successfully took from the WebUI is also gone (well, I can’t find it).

I hope there is a simple explanation and a way to get back the server created.

Looking forward to hearing from you,


Hi, I’m sorry to hear you’ve been running into this issue. Unfortunately, I don’t really know docker…at all. The basic concept I’ve grasped and I’ve deployed a few, but I haven’t worked with it enough to know what part of the power failure is making the data–surely somewhere on that drive–not appear as you expect it to.

You mention a number of paths, /usr/minetest and /mnt/appdata/minecraftos which I am not entirely sure how they fit in. Using the docker file from the git repo itself, I get MineOS up and running, but I’ve never needed to mount docker.img.

Have you changed where the volume is saved on your host machine? Take a look at this page on the docker docs and see if you can use it to determine the location of your container’s mounts on your host system; I think within there you should be able to find your lost files and then you can get a docker up again with the files property detected.

I made a post also in the appropriate unRaid forum in case it was an OS issue, and it turns out it (sort of) was.

I didn’t follow the recommendations in setting up the docker as it was the first docker I was setting up just to play around, but everything was working fine and was really happy with it so I didn’t bother checking it again.

It seems that mounting staff between the container and /mnt/appdata is not the way to go, as /mnt/appdata is actually a temp / ram drive and after a reset / power failure all contents are gone. I 'm new to Linux OSes so there you have it, should have read sooner the relating bookmarked page.

I made a proper configuration this time with the mounting being on a share on the disk and I made some rebooting tests to verify that minecraft world / server data will not go away, so everything is ok now.

Btw thank you for coming back to me,