Add mc-backup Sidecar

[merkinbob]

Add mc-backup sidecar for minecraft-server.

Ready for testing:

• tar
• rclone
• restic

Please be careful with Restic, take note of the HOSTNAME conflict

Tested:

• tar method
• rclone method
• restic method

I believe restic and rclone are setup right, but i have no way of testing these

Solves #91

[merkinbob]

is there any interest in rclone or restic for the chart?

[itzg]

is there any interest in rclone or restic for the chart?

People use those methods, but can be included in a follow up PR.

[itzg]

Please take a look at the build failure.

[merkinbob]

is there any interest in rclone or restic for the chart?

People use those methods, but can be included in a follow up PR.

in theory restic is done, but i don't know how to test it. rclone i need to add a config map for.

[merkinbob]

Please take a look at the build failure.

will do

[merkinbob]

@itzg I think this now adds restic, and rclone capabilities, i didn't test it tho. tar still works, linting should pass.

[merkinbob]

3rd time the charm?

[cburza]

@merkinbob I will attempt to test rclone.

[cburza]

@merkinbob I am getting the following error on container startup:

time="2022-01-11T18:06:19Z" level=fatal msg="Failed to run sub-command" error="fork/exec /usr/bin/backup: operation not permitted"

I have RCON enabled in the server. I am setting no other values for mcbackup other than enabled: true.

Do you perhaps know what could be causing it?

[merkinbob]

@merkinbob I am getting the following error on container startup:

time="2022-01-11T18:06:19Z" level=fatal msg="Failed to run sub-command" error="fork/exec /usr/bin/backup: operation not permitted"

I have RCON enabled in the server. I am setting no other values for mcbackup other than enabled: true.

Do you perhaps know what could be causing it?

my guess is it's not happy with empty dir for the backup volume.

Below is all i have set in my values.yaml file for my argocd deployment.

mcbackup:
  enabled: true     

  persistence:
    storageClass: "csi-cephfs-sc"
    backupDir:
      enabled: true
      Size: 500Gi

As soon as I set backupDir: enabled: false I got the same crashloop

I think the issue is in here somewhere

https://github.com/itzg/entrypoint-demoter

I could try to set the UID and GID ENV to match the security context.

After some research, it appears the emptydir is owned by root:root. This is an old issue in k8s, and not resolved.

kubernetes/kubernetes#2630

[itzg]

Final review looks great! Ready for a merge?

[merkinbob]

Final review looks great! Ready for a merge?

one concern I have about restic is the HOSTNAME note on your mc-backup docs. Other than that, I think this is a good start. I hope someone finds this useful.

[itzg]

Just discovered there's a --hostname. I wrote up itzg/docker-mc-backup#55 , but I think the chart changes will be good even with that.