From Notes Wiki
CentOS 7.x network bonding
It is possible to combine to NICs in a single bond interface for redundancy, performance, etc. reasons. To configure bond on top of two physical interfaces use following steps:
- Identify two identical interfaces for creating bond. These interfaces should have same speed and should be connected to same VLAN(s).
- Go to /etc/sysconfig/network-scripts/ folder
- Create 'ifcfg-bond0' with contents similar to:
- BONDING_OPTS="miimon=0 updelay=0 downdelay=0 mode=4"
- where mode=4 refers to 802.3ad or LACP. For other types of mode such as balance-rr, active-backup, balance-xor, etc. refer to reference links at the end
- In case of less information on network switch end or while using unmanageable switches, use mode=5 as that seems to be able to detect interfaces going up or down properly.
- Update interface configuration files to depend on bond using:
- where ens0 is the name of one of the two ethernet interfaces to be added to bond
- Do the same for second ethernet interface
- Restart network for settings to take effect:
- systemctl restart network
- Use following to make sure bond is formed properly:
- cat /proc/net/bonding/bond0
- If in cat /proc/net/bonding/bond0 output only one interface is shown and other is not showing up then validate SLAVE=yes and MASTER=bond0 are present in the interface configuration file for the other interface.
- If bond0 itself is not getting created make sure DEVICE=bond0, NAME=bond0 etc. is present in ifcfg-bond0 file