How to Change the IPv4 Address in AlmaLinux

How to Change the IPv4 Address in AlmaLinux

Changing the IPv4 address on an AlmaLinux system is a common administrative task—whether you're configuring a server with a static IP, moving to a new network, or troubleshooting connectivity. AlmaLinux (8 and 9) uses NetworkManager by default, which provides multiple ways to manage network settings.

This guide explains the recommended and alternative methods step by step.

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Understanding IPv4 Configuration in AlmaLinux

In modern AlmaLinux systems:

• NetworkManager controls network interfaces.

• Configuration can be done using:

  • nmcli (command line)

  • nmtui (text-based interface)

  • Manual configuration files

Most systems—especially servers and VPS instances—use predictable interface names like:

• ens33

• enp0s3

• eth0

You can check your interface name with:

ip link

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Method 1: Using nmcli (Recommended Method)

nmcli is the official command-line tool for managing NetworkManager.

Step 1: List Active Connections

nmcli connection show

Take note of the connection name (for example: System ens33).

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Step 2: Set a Static IPv4 Address

Replace the example values with your network details:

nmcli connection modify "System ens33" \
ipv4.addresses 192.168.1.100/24 \
ipv4.gateway 192.168.1.1 \
ipv4.dns "8.8.8.8 8.8.4.4" \
ipv4.method manual

Explanation:

• 192.168.1.100/24 → IP address and subnet prefix

• 192.168.1.1 → Default gateway

• DNS servers → Google DNS (example)

• manual → Enables static configuration

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Step 3: Restart the Connection

nmcli connection down "System ens33"
nmcli connection up "System ens33"

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Step 4: Verify the Changes

ip a

or

nmcli device show

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Switching Back to DHCP

If you want the system to automatically obtain an IP address:

nmcli connection modify "System ens33" ipv4.method auto
nmcli connection up "System ens33"

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Method 2: Using nmtui (Text-Based UI)

If you prefer a guided interface:

nmtui

Steps:

1. Select Edit a connection

2. Choose your network interface

3. Change IPv4 configuration from Automatic to Manual

4. Enter:

   • IP address

   • Gateway

   • DNS servers

5. Save and activate the connection

This method is useful for administrators who prefer interactive configuration over command-line arguments.

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Method 3: Editing Configuration Files Manually

In AlmaLinux 8 and 9, NetworkManager stores configuration files in:

/etc/NetworkManager/system-connections/

Older legacy configurations (less common in modern AlmaLinux) may use:

/etc/sysconfig/network-scripts/

Example static configuration in legacy format:

BOOTPROTO=none
ONBOOT=yes
IPADDR=192.168.1.100
PREFIX=24
GATEWAY=192.168.1.1
DNS1=8.8.8.8

After editing, restart NetworkManager:

systemctl restart NetworkManager

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Important Considerations

1. Avoid IP Conflicts

Ensure the IP address is not already assigned to another device on the network.

2. Be Careful on Remote Servers

If you're connected via SSH, changing the IP incorrectly can disconnect your session. Always confirm:

• Correct gateway

• Correct subnet mask

• Correct DNS

3. Verify Network Status

Check status with:

nmcli device status

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Conclusion

Changing the IPv4 address in AlmaLinux is straightforward thanks to NetworkManager. The recommended method is using nmcli, especially for servers and automation. For beginners or quick configuration, nmtui provides a simple interface.

By understanding these methods, system administrators can confidently manage network settings on AlmaLinux systems in both desktop and server environments.