How to Configure rsync as a Daemon

 

What is rsync?

Rsync is a free software utility for Unix- and Linux-like systems that copies files and directories from one host to another. Rsync, which stands for “remote sync”, is a remote and local file synchronization tool. It uses an algorithm that minimizes the amount of data copied by only moving the portions of files that have changed. 

Activity

In this example I am going to configure rsync as a daemon service. For that we need two Linux PCs. For this activity I am using CentOS-7.

Step 1: Install and enable rsync service

Open the terminal and execute below command to install rsync package on both servers.

# yum install rsync 

To enable the service, execute this command. No need to enable the service on both server. You have to pick one server as your source.

# systemctl enable rsyncd

 

Step 2: Edit rsync Configuration File

rsync configuration file available under "/etc/rsyncd.conf". You can use any text file editor to edit the file. Add below configurations to config file.

pid file = /var/run/rsyncd.pid

lock file = /var/run/rsync.lock

log file = /var/log/rsync.log

port = 12000

uid = root

gid = root

[web-public]

path = /usr/share/html

comment = Web Static Files

read only = false

timeout = 300

After save the config file, start the rsyncd service. 

# systemctl start rsyncd

Verify the service is running with this command.

# systemctl status rsyncd

Step 3: Sync Files

Now go to another server and check whether file are available to sync. You can execute below command to test your connection to the rsync daemon and find which paths are available to you.

# /bin/rsync -rda rsync://192.168.1.17:12000

Execute below command to sync the files to your local pc.

# /bin/rsync -rda rsync://192.168.1.17:12000/web-public /usr/share/html/

Step 4: Secure the rsync

• Allow only for specific source IPs

To do this add below configurations parameters to rsync config file and restart the service.

hosts allow = 192.168.1.18

hosts deny = *

pid file = /var/run/rsyncd.pid

lock file = /var/run/rsync.lock

log file = /var/log/rsync.log

port = 12000

uid = root

gid = root

•  Adding Usernames and Passwords

You can make your rsync daemon more secure by adding a username and password requirement in its configuration file. Open /etc/rsyncd.conf add these configurations.

[web-public]

path = /usr/share/html

comment = Web Static Files

read only = false

timeout = 300

auth users = rsync1,rsync2

secrets file = /etc/rsyncd.secrets

Now create credential file "/etc/rsyncd.secrets" and add these users.

rsync1:123123

rsync2:123123

rsync3:123123

Once you have saved this file, secure it so only the root user can read or edit it.

# chmod 600 /etc/rsyncd.secrets 

Now restart the service and very the configurations. First try to sync in normal way without an user.

# /bin/rsync -rda rsync://192.168.1.17:12000/web-public /usr/share/html

It will prompt for password. Now try to sync the files by specifying the user we put in the "rsyncd.secrets" file.

# /bin/rsync -rda rsync://rsync1@192.168.1.17:12000/web-public /usr/share/html