This will cover configuring a rsync server to allow rsync clients to connect.
Configure rsyncd
rsyncd.conf
sudo vi /etc/rsyncd.conf
max connections = 2
log file = /var/log/rsync.log
timeout = 300
[apps]
comment = Public Share
path = /media/apps
read only = no
list = yes
uid = root
gid = root
auth users = backup
secrets file = /etc/rsyncd.secrets
Create the password file
sudo vi /etc/rsyncd.secrets
backup:backup
Now update the permissions
sudo chmod 600 /etc/rsyncd.secrets
Update the defaults file
sudo vi /etc/default/rsync
...
RSYNC_ENABLE=true
...