Overview ¶

The author acknowledges this approach is “probably not best practice” and recommends testing before implementation. He describes it as a temporary workaround rather than a long-term solution.

The Problem ¶

Hetzner’s new cloud services lack storage options comparable to Amazon S3. While their legacy platform offers affordable storage via FTP or SMB, it doesn’t support NFS (required by Rancher). The author needed a method to mount Docker volumes on SMB endpoints.

Solution Architecture ¶

The technique involves mounting a Docker volume’s folder from external storage. It works best for non-latency-sensitive applications like backup storage, not databases.

Target volume location: /var/lib/docker/volumes/db-backups/_data

Implementation Steps ¶

1. Install CIFS utilities ¶

apt-get install cifs-utils

2. Create credentials file ¶

Create /etc/backup-credentials.txt:

username=someuser
password=somesecret

3. Add to /etc/fstab ¶

//smb.host/path /var/lib/docker/volumes/db-backups/_data cifs rw,credentials=/etc/backup-credentials.txt,uid=0,gid=0,file_mode=0660,dir_mode=0770 0 0

4. Mount the volume ¶

mount -a

5. Restart Docker containers ¶

Restart Docker containers using the volume.

Testing & Results ¶

The author verified functionality by accessing the storage box via LFTP and confirming successful backup file creation.

Summary ¶

This technique provides cost-effective storage integration for Docker deployments but requires direct server administration, contradicting container orchestration best practices.