18.7. Configuring a network bond by using the network RHEL system role
You can use the network RHEL system role to configure a network bond and, if a connection profile for the bond’s parent device does not exist, the role can create it as well.
You can combine network interfaces in a bond to provide a logical interface with higher throughput or redundancy. To configure a bond, create a NetworkManager connection profile. By using Ansible and the network RHEL system role, you can automate this process and remotely configure connection profiles on the hosts defined in a playbook.
Prerequisites
- You have prepared the control node and the managed nodes.
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudopermissions for these nodes. - Two or more physical or virtual network devices are installed on the server.
Procedure
Create a playbook file, for example,
~/playbook.yml, with the following content:--- - name: Configure the network hosts: managed-node-01.example.com tasks: - name: Bond connection profile with two Ethernet ports ansible.builtin.include_role: name: redhat.rhel_system_roles.network vars: network_connections: # Bond profile - name: bond0 type: bond interface_name: bond0 ip: dhcp4: yes auto6: yes bond: mode: active-backup state: up # Port profile for the 1st Ethernet device - name: bond0-port1 interface_name: enp7s0 type: ethernet controller: bond0 state: up # Port profile for the 2nd Ethernet device - name: bond0-port2 interface_name: enp8s0 type: ethernet controller: bond0 state: upThe settings specified in the example playbook include the following:
type: <profile_type>- Sets the type of the profile to create. The example playbook creates three connection profiles: One for the bond and two for the Ethernet devices.
dhcp4: yes- Enables automatic IPv4 address assignment from DHCP, PPP, or similar services.
auto6: yes-
Enables IPv6 auto-configuration. By default, NetworkManager uses Router Advertisements. If the router announces the
managedflag, NetworkManager requests an IPv6 address and prefix from a DHCPv6 server. mode: <bond_mode>Sets the bonding mode. Possible values are:
-
balance-rr(default) -
active-backup -
balance-xor -
broadcast -
802.3ad -
balance-tlb -
balance-alb.
Depending on the mode you set, you need to set additional variables in the playbook.
-
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.network/README.mdfile on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.ymlNote that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Verification
Temporarily remove the network cable from one of the network devices and check if the other device in the bond is handling the traffic.
Note that there is no method to properly test link failure events using software utilities. Tools that deactivate connections, such as
nmcli, show only the bonding driver’s ability to handle port configuration changes and not actual link failure events.