Moving away from GlusterFS to a shared folder mounted via sshfs for my cluster storage

Context

As I written at the beginning of the selfhosting series about my docker swarm cluster, I have used so far a GlusterFS volume mounted on all nodes of the swarm. It has worked well until now, but the truth is I believe it was too heavy for the raspberry pi (mainly on the pi2 and 3) and had a few issues with it over the years (issues when mounting the drive with only part of the data and other small glusterfuck^^).

As I finally invested and installed a NAS¹ at home recently (more on this later), I decided to leverage it for the storage of the cluster.

Disclaimer: I know that it is not the best way of managing this, specially when having a bigger usage and that GlusterFS is made for this and is one of the best choice. But for a selfhosted cluster with almost no traffic based on raspberry pi, it was overkilled.

Setup

On all raspberry pi, I had to install sshfs:

    sudo apt install sshfs

Then, enable the user_allow_other to manage access permissions and right through sshfs:

    sudo vim /etc/fuse.conf

And uncomment user_allow_other.

Create the directory where the remote directory will be mounted, eg (on all cluster’s node):

    sudo mkdir -p /mnt/nas_storage/

Now, create an ssh key on all nodes if it is not already the case (without passphrase) with ssh-keygen.

Add each keys in the authorized_keys files of the right user.

You can test if it works as expected (and add the server in the known_hosts file):

    sshfs -o allow_other user@server:/path/to/remote/directory/ /mnt/nas_storage

If your data are in /mnt/nas_storage, it works. Now you can unmount it for now:

    fusermount -u /mnt/nas_storage

To automount on demand the sshfs directory, edit the /etc/fstab file and add:

    user@server:/path/to/remote/directory /mnt/nas_storage/ fuse.sshfs noauto,x-systemd.automount,_netdev,users,IdentityFile=/path/to/sshkey.pub,allow_other,reconnect 0 0