RHCSA - Operate Running Systems: Start, Stop, & Check the Status of Network Services

A network service refers to a software application or process that runs in the background and provides specific network-related functionality or resources to other devices or applications on the network. These services allow devices to communicate, share data, and perform various network-related tasks.

Common Network Services

The below table depicts a few common network services:

Application Name	Service Name	Description
Apache HTTP Server	httpd	A powerful web server software for hosting websites.
OpenSSH Server	sshd	Enables secure remote login and file transfer (SSH).
Postfix	postfix	Mail server software for sending and receiving emails.
Samba	smb	Allows file and printer sharing with Windows systems (SMB).
NetworkManager	NetworkManager	Provides network configuration and connection management.
BIND	named	Implements DNS functionality, translating domain names.
NTP client/server	chronyd	A versatile implementation of the Network Time Protocol.
DHCP	dhcpd	Automatically assigns IP addresses to devices on a network.
firewalld	firewalld	Firewall management tool for dynamically managing rules.

Managing Network Services

You can start, stop and check the status of network services by using the systemctl command. You will need to use sudo or run the commands as root when altering the service state, however this is not required when checking the status of a service.

The below table shows the systemctl options in relation to the exam objective:

Command	Description
`sudo systemctl start <service>`	Start a service immediately.
`sudo systemctl stop <service>`	Stop a running service.
`sudo systemctl restart <service>`	Restart a running service.
`sudo systemctl reload <service>`	Reload the configuration of a running service.
`sudo systemctl enable <service>`	Enable a service to start on boot.
`sudo systemctl disable <service>`	Disable a service from starting on boot.
`systemctl status <service>`	Show the status and information of a service.
`systemctl is-active <service>`	Check if a service is currently active.
`systemctl is-enabled <service>`	Check if a service is set to start on boot.
`systemctl is-failed <service>`	Check if a service is in a failed state.

The following exercise will get you practicing managing a network service:

It is very important you know how to enable or disable a service for boot time startup. An exam objective could very well be ensuring that a service is in a particular state.

Manage the chronyd service:

Ensure the service is stopped:

sudo systemctl stop chronyd

Disable the service:

sudo systemctl disable chronyd

Check the full status of the service, which shows latest log entries for the service and information on whether the service is enabled (start on boot) or active (currently running or not):

systemctl status chronyd

Press the Q key to return to the prompt.

Perform a check on just the active state:

systemctl is-active chronyd

Perform a check to see if the service is enabled to start on boot:

systemctl is-enabled chronyd

Enable the service to start on boot:

sudo systemctl enable chronyd

Start the service back up:

sudo systemctl start chronyd

Check the status of the service again to ensure it is running and enabled.

systemctl status chronyd

Press the Q key to return to the prompt.

Support DTV Linux

Click on each book below to review & buy on Amazon. As an Amazon Associate, I earn from qualifying purchases.

NordVPN ®: Elevate your online privacy and security. Grab our Special Offer to safeguard your data on public Wi-Fi and secure your devices. I may earn a commission on purchases made through this link.