NIC teaming on Centos 7

I’ve heard a lot about link aggregation, teaming or bonding but I’ve never tried it. Until now. In this post I will demonstrate how to setup NIC teaming on CentOS 7 virtual host.

Setup NIC teaming on Server

I can see 2 network cards (both with IP address assigned by DHCP):

nmcli device
DEVICE  TYPE      STATE      CONNECTION         
eth0    ethernet  connected  System eth0        
eth1    ethernet  connected  Wired connection 1 
lo      loopback  unmanaged  --                 
[root@centos-team ~]# nmcli connection
NAME                UUID                                  TYPE            DEVICE 
Wired connection 1  b709aa19-505f-4b7a-8513-a0bf8bfb3ff8  802-3-ethernet  eth1   
System eth0         4628dca0-dc29-4c47-9f4a-743a08010ea5  802-3-ethernet  eth0   
[root@centos-team ~]# ip address list
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:c6:b8:9f brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.41/24 brd 192.168.122.255 scope global dynamic eth0
       valid_lft 3536sec preferred_lft 3536sec
    inet6 fe80::5054:ff:fec6:b89f/64 scope link 
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:ee:47:16 brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.187/24 brd 192.168.122.255 scope global dynamic eth1
       valid_lft 3538sec preferred_lft 3538sec
    inet6 fe80::5054:ff:feee:4716/64 scope link 
       valid_lft forever preferred_lft forever

Now I want to team these to NICs together. I will assign static IP adress to teamed device (team0).

I’ve created two configuration for each NIC – ifcfg-eth0 and ifcfg-eth1:

[root@centos-team network-scripts]# cat ifcfg-eth0
DEVICE="eth0"
DEVICETYPE="TeamPort"
ONBOOT="yes"
BOOTPROTO="none"
TEAM_MASTER="team0"
[root@centos-team network-scripts]# cat ifcfg-eth1
DEVICE="eth1"
DEVICETYPE="TeamPort"
ONBOOT="yes"
BOOTPROTO="none"
TEAM_MASTER="team0"

DEVICETYPE line defines that this devices is part of team. TEAM_MASTER defines to which master device it belongs. Next step is to define team device:

[root@centos-team network-scripts]# cat ifcfg-team0 
DEVICE="team0"
DEVICETYPE="Team"
ONBOOT="yes"
BOOTPROTO="none"
NETMASK=255.255.255.0
IPADDR=192.168.122.200
TEAM_CONFIG='{"runner": {"name": "roundrobin"}}'

Device will be configured with IP address of 192.168.122.200. Parameter TEAM_CONFIG stores teamd configuration. For more information seeman teamd.conf. This config says that load on team device (team0) will be split on slave devices (eth0 and eth1) in round-robin fashion. It will basically join these slave interfaces together to achieve double network bandwidth. After reboot it looks like this:

[root@centos-team ~]# ip address list
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master team0 state UP qlen 1000
    link/ether 52:54:00:c6:b8:9f brd ff:ff:ff:ff:ff:ff
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master team0 state UP qlen 1000
    link/ether 52:54:00:c6:b8:9f brd ff:ff:ff:ff:ff:ff
4: team0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP 
    link/ether 52:54:00:c6:b8:9f brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.200/24 brd 192.168.122.255 scope global team0
       valid_lft forever preferred_lft forever
    inet6 fe80::5054:ff:fec6:b89f/64 scope link tentative dadfailed 
       valid_lft forever preferred_lft forever
[root@centos-team ~]# nmcli connection
NAME         UUID                                  TYPE            DEVICE 
Team team0   702de3eb-2e80-897c-fd52-cd0494dd8123  team            team0  
System eth1  9c92fad9-6ecb-3e6c-eb4d-8a47c6f50c04  802-3-ethernet  eth1   
System eth0  5fb06bd0-0bb0-7ffb-45f1-d6edd65f3e03  802-3-ethernet  eth0   
[root@centos-team ~]# nmcli device
DEVICE  TYPE      STATE      CONNECTION  
eth0    ethernet  connected  System eth0 
eth1    ethernet  connected  System eth1 
team0   team      connected  Team team0  
lo      loopback  unmanaged  --

To see wich values you can insert on the “TEAM_CONFIG=” flag their is i quick example of the configurations files you can see here and choose wich configuration fits best:

ls /usr/share/doc/teamd-*/example_configs/
activebackup_arp_ping_1.conf  activebackup_multi_lw_1.conf   loadbalance_2.conf
activebackup_arp_ping_2.conf  activebackup_nsna_ping_1.conf  loadbalance_3.conf
activebackup_ethtool_1.conf   broadcast.conf                 random.conf
activebackup_ethtool_2.conf   lacp_1.conf                    roundrobin_2.conf
activebackup_ethtool_3.conf   loadbalance_1.conf             roundrobin.conf

To view one of the included files, such as activebackup_ethtool_1.conf, enter the following command:

cat /usr/share/doc/teamd-*/example_configs/activebackup_ethtool_1.conf
{
	"device":	"team0",
	"runner":	{"name": "activebackup"},
	"link_watch":	{"name": "ethtool"},
	"ports":	{
		"eth1": {
			"prio": -10,
			"sticky": true
		},
		"eth2": {
			"prio": 100
		}
	}
}