Configuring a BackupPC Linux Client
You can use the provided bash shell script (you’ll have to add your server’s SSH Public Key to it):
Or do it manually, as depicted below.
First you must create the BackupPC User for the server to be able to copy files.
# Create the BackupPC User
adduser backuppc --disabled-password
# Ensure it has no password access (only logon with ssh key)
passwd -l backuppc
If you do not have these dependencies installed, install them.
apt update -y && apt install sudo rsync
Add your backuppc user to the sudoers (only allow the rsync command)
# Create the file
touch /etc/sudoers.d/backuppc
# Use the correct permissions on the file
chmod 440 /etc/sudoers.d/backuppc
# Add the command to your sudoers
echo -e "backuppc ALL=NOPASSWD: /usr/bin/rsync * \n" > /etc/sudoers.d/backuppc
# Check that it parses properly
visudo -c
Now create the .ssh directory in /home/backuppc and copy the server’s ssh public key.
In the server:
# Do a cat of the public key
cat /var/lib/backuppc/id_rsa.pub
In the client:
# Create the directory
mkdir /home/backuppc/.ssh
# Copy your key to the authorized_keys file
key="your_pubkey"
echo $key > /home/backuppc/.ssh/authorized_keys
# Ensure known_hosts exists
touch /home/backuppc/.ssh/known_hosts
# Ensure the correct ownership and permissions
chown -R backuppc:backuppc /home/backuppc/.ssh
chmod 700 /home/backuppc/.ssh
chmod 600 /home/backuppc/.ssh/*
# Do a keyscan of the server
backuppc_server_ip="127.0.0.1" # Use the IP your server has
ssh-keyscan "$backuppc_server_ip" >> /home/backuppc/.ssh/known_hosts
Also you will need to make sure that your Client SSH Server allows pubkey authentication.
# If you want you can put this in a bash script and execute it
# or do it manually.
sshd_config_path="/etc/ssh/sshd_config"
if [[ $(grep "#AuthorizedKeysFile" "$sshd_config_path") ]]; then
echo "Enabled the AuthorizedKeysFile parameter in $sshd_config_path"
sed -i "s/^#\(AuthorizedKeysFile.*\)$/\1/g" "$sshd_config_path"
fi
Then go back to your server and do the following:
# Use your client IP here
client_ip="127.0.0.1"
sudo -u backuppc ssh $client_ip
# You should be logged into the client, you can exit immediately by
# writing "exit" or pressing CTRL+D
Then go to your BackupPC GUI and Add the host!