How to Configure Network Teaming on AlmaLinux

Network teaming is a method of combining multiple network interfaces into a single logical interface for improved performance, fault tolerance, and redundancy. Unlike traditional bonding, network teaming provides a more flexible and modern approach to network management, with support for advanced load balancing and failover capabilities. AlmaLinux, a stable and secure enterprise-grade Linux distribution, fully supports network teaming, making it a great choice for deploying reliable network setups.

This guide will walk you through the step-by-step process of configuring network teaming on AlmaLinux.

Why Configure Network Teaming?

Network teaming provides several benefits, including:

1. High Availability: Ensures uninterrupted network connectivity by automatically redirecting traffic to a healthy interface in case of failure.
2. Improved Performance: Combines the bandwidth of multiple network interfaces for increased throughput.
3. Scalability: Allows for dynamic addition or removal of interfaces without service disruption.
4. Advanced Modes: Supports multiple operational modes, including active-backup, load balancing, and round-robin.

Prerequisites

Before you start, ensure the following:

1. AlmaLinux Installed: A clean or existing installation of AlmaLinux with administrative access.
2. Multiple Network Interfaces: At least two physical or virtual NICs (Network Interface Cards) for teaming.
3. Root or Sudo Access: Required for network configuration.
4. Stable Internet Connection: To download and install necessary packages.

Step 1: Update the System

Begin by updating your system to ensure all packages are up-to-date:

sudo dnf update -y

This ensures you have the latest bug fixes and features.

Step 2: Install Required Tools

Network teaming on AlmaLinux uses the NetworkManager utility, which is installed by default. However, you should verify its presence and install the necessary tools for managing network configurations.

Verify NetworkManager

Ensure that NetworkManager is installed and running:

sudo systemctl status NetworkManager

If it’s not installed, you can install it using:

sudo dnf install -y NetworkManager

Install nmcli (Optional)

The nmcli command-line tool is used for managing network configurations. It’s included with NetworkManager, but verify its availability:

nmcli --version

Step 3: Identify Network Interfaces

Identify the network interfaces you want to include in the team. Use the ip command to list all network interfaces:

ip link show

You’ll see a list of interfaces, such as:

1: lo: <LOOPBACK,UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000

Identify the NICs (e.g., enp0s3 and enp0s8) that you want to include in the team.

Step 4: Create a Network Team

Create a new network team interface using the nmcli command.

Create the Team Interface

Run the following command to create a new team interface:

sudo nmcli connection add type team con-name team0 ifname team0 config '{"runner": {"name": "activebackup"}}'

• team0: The name of the team interface.
• activebackup: The teaming mode. Other options include loadbalance, broadcast, and roundrobin.

Step 5: Add Network Interfaces to the Team

Add the physical interfaces to the team interface.

Add an Interface

Add each interface (e.g., enp0s3 and enp0s8) to the team:

sudo nmcli connection add type team-slave con-name team0-slave1 ifname enp0s3 master team0
sudo nmcli connection add type team-slave con-name team0-slave2 ifname enp0s8 master team0

• team0-slave1 and team0-slave2: Connection names for the slave interfaces.
• enp0s3 and enp0s8: Physical NICs being added to the team.

Step 6: Configure IP Address for the Team

Assign an IP address to the team interface.

Static IP Address

To assign a static IP, use the following command:

sudo nmcli connection modify team0 ipv4.addresses 192.168.1.100/24 ipv4.method manual

Replace 192.168.1.100/24 with the appropriate IP address and subnet mask for your network.

Dynamic IP Address (DHCP)

To configure the team interface to use DHCP:

sudo nmcli connection modify team0 ipv4.method auto

Step 7: Bring Up the Team Interface

Activate the team interface to apply the configuration:

sudo nmcli connection up team0

Activate the slave interfaces:

sudo nmcli connection up team0-slave1
sudo nmcli connection up team0-slave2

Verify the status of the team interface:

nmcli connection show team0

Step 8: Verify Network Teaming

To ensure the team is working correctly, use the following commands:

Check Team Status

View the team configuration and status:

sudo teamdctl team0 state

The output provides detailed information about the team, including active interfaces and the runner mode.

Check Connectivity

Ping an external host to verify connectivity:

ping -c 4 8.8.8.8

Simulate Failover

Test the failover mechanism by disconnecting one of the physical interfaces and observing if traffic continues through the remaining interface.

Step 9: Make the Configuration Persistent

The configurations created using nmcli are automatically saved and persist across reboots. To confirm, restart the server:

sudo reboot

After the reboot, check if the team interface is active:

nmcli connection show team0

Step 10: Advanced Teaming Modes

Network teaming supports multiple modes. Here’s an overview:

1. activebackup:

   • Only one interface is active at a time.
   • Provides redundancy and failover capabilities.

2. loadbalance:

   • Distributes traffic across all interfaces based on load.

3. broadcast:

   • Sends all traffic through all interfaces.

4. roundrobin:

   • Cycles through interfaces for each packet.

To change the mode, modify the team configuration:

sudo nmcli connection modify team0 team.config '{"runner": {"name": "loadbalance"}}'

Restart the interface:

sudo nmcli connection up team0

Troubleshooting

1. Team Interface Fails to Activate:

   • Ensure all slave interfaces are properly connected and not in use by other connections.

2. No Internet Access:

   • Verify the IP configuration (static or DHCP).
   • Check the firewall settings to ensure the team interface is allowed.

3. Failover Not Working:

   • Use sudo teamdctl team0 state to check the status of each interface.

4. Conflicts with Bonding:

   • Remove any existing bonding configurations before setting up teaming.

Conclusion

Network teaming on AlmaLinux provides a reliable and scalable way to improve network performance and ensure high availability. By combining multiple NICs into a single logical interface, you gain enhanced redundancy and load balancing capabilities. Whether you’re setting up a server for enterprise applications or personal use, teaming ensures robust and efficient network connectivity.

With this guide, you’ve learned how to configure network teaming using nmcli, set up advanced modes, and troubleshoot common issues. AlmaLinux’s stability and support for modern networking tools make it an excellent platform for deploying network teaming solutions. Happy networking!