Using Exoscale Compute as a Dedicated Backup Server

Create Object Storage Bucket

Create bucket in Exoscale Portal

1. In the Exoscale portal, navigate to Storage
2. Click Add to create a new bucket
3. Configure:
   • Zone: Select region (note the name, it’ll be used to connect to the container e.g ch-dk-2)
   • Name: plakar-backups (must be globally unique)
4. Click Add

Generate IAM API Keys

1. In the Exoscale portal, navigate to IAM → Keys
2. Click on Add to create new API keys, then provide a name and role, then click Create.
3. Copy the key and secret to a secure environment (you cannot see the secret once you leave the page)

Create SSH Keypair

1. Generate SSH key locally and copy the public key:

$ ssh-keygen -t ed25519 -f ~/.ssh/id_exoscale -C "exoscale-backup"
$ cat ~/.ssh/id_exoscale.pub

2. In the Exoscale portal, navigate to Compute → SSH Keys
3. Click on Add then enter a name for the SSH Key and paste in the public key then click Import.

Provision Backup Compute Instance

Create compute instance

1. In the Exoscale Portal, navigate to Compute → Instances
2. Click Add
3. Configure:
   • Name: plakar-backup
   • Template: Ubuntu 24.04 LTS
   • Zone: Same as Object Storage bucket (recommended for better performance)
   • Instance Type: Small (2 vCPUs, 2 GB RAM) or any other you prefer
   • SSH Key: Select the SSH key we created before from the dropdown
4. Click Add to provision your compute

Setup security group rules

1. Once the compute is provisioned, navigate to Compute → Security Groups
2. By default the compute will be assigned the default security group, click on the actions on default then click on Details
3. On the next page click on Add Rule
4. Configure:
   • Flow direction: Ingress
   • Protocol: TCP
   • Source Type: CIDR
   • Sources: 0.0.0.0/0 allows SSH from anywhere (for better security use your IP Address here)
   • Start & End port: 22
   • A description for the rule e.g. SSH Access
5. Click on Create

Initial connection

Once instance is running, note the public IP and connect:

$ ssh ubuntu@<instance-ip>

Install Plakar

Install Plakar on the instance using the Plakar Installation Guide

Configure Object Storage

Install S3 integration

$ plakar login -email you@example.com
$ plakar pkg add s3

Add storage connector

$ plakar store add exoscale-sos-backups \
  location=s3://<SOS_ENDPOINT>/<BUCKET_NAME> \
  access_key=<YOUR_ACCESS_KEY> \
  secret_access_key=<YOUR_SECRET_KEY> \
  use_tls=true \
  passphrase='<YOUR_SECURE_PASSPHRASE>'

Replace:

• <SOS_ENDPOINT>: using the format sos-{zone}.exo.io where zone is one we selected for the bucket e.g sos-ch-dk-2.exo.io
• <BUCKET_NAME>: e.g., plakar-backups
• <YOUR_ACCESS_KEY> and <YOUR_SECRET_KEY>: From bucket API credentials
• <YOUR_SECURE_PASSPHRASE>: Strong passphrase for encryption

Initialize Kloset Store

$ plakar at "@exoscale-sos-backups" create

Configure SSH Access to Source Servers

Install SFTP integration

$ plakar pkg add sftp

Generate SSH keys for backups

$ ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519_plakar -C "plakar@backup"

Press Enter for no passphrase.

Copy keys to source servers

$ ssh-copy-id -i ~/.ssh/id_ed25519_plakar.pub user@source-server-1
$ ssh-copy-id -i ~/.ssh/id_ed25519_plakar.pub user@source-server-2

Test access:

$ ssh -i ~/.ssh/id_ed25519_plakar user@source-server-1 'echo "Success"'

Create SSH aliases

$ cat >> ~/.ssh/config << 'EOF'
Host source-1
  HostName source-server-1.example.com
  User backupuser
  Port 22
  IdentityFile ~/.ssh/id_ed25519_plakar

Host source-2
  HostName source-server-2.example.com
  User backupuser
  Port 22
  IdentityFile ~/.ssh/id_ed25519_plakar
EOF

Test:

$ ssh source-1 'echo "Alias works"'

Configure Backup Sources

Add source connectors for each server:

$ plakar source add web-server-1 sftp://source-1:/var/www
$ plakar source add web-server-2 sftp://source-2:/var/www

Verify:

$ plakar source show

Test Backup

Run a manual backup to verify configuration:

# Single source
$ plakar at "@exoscale-sos-backups" backup "@web-server-1"

# Multiple sources
$ plakar at "@exoscale-sos-backups" backup "@web-server-1" "@web-server-2"

List snapshots:

$ plakar at "@exoscale-sos-backups" ls

Schedule Automatic Backups

For scheduler configuration and systemd service setup, follow the same steps as the OVHcloud backup server guide, replacing:

• @ovhcloud-s3-backups with @exoscale-sos-backups
• ubuntu with your actual username if different

The scheduler configuration, systemd services, and web UI setup are identical on any Linux machine.