Linux Bonding Mode 1 Active-Backup

Question

Is it possible both NIC configured as Linux Bonding Mode 1 sending traffic? I have a strange case where both NIC is set as Linux Bonding Mode 1 (active-backup) and connect to two different switches (connected each other through vpc-peer). For some reason, the backup/slave NIC also send the traffic to the switch, the result : the switch port is learning the mac address and the traffic is stop since both switch learn the same mac address from both NIC. Thanks alot

Check the traffic on backup link with tcpdump. What are the packets being sent? — Anton Danilov, Dec 07 '18 at 09:57

score 2 · Answer 1 · answered Dec 07 '18 at 10:18

When bonding mode=1, only the active NIC is allowed to present the MAC address. So if both NICS are presenting the MAC addresses, then the bonding interfaces are not configured correctly.

The bonding module should be loaded: lsmod | grep bond ; modinfo bonding

Check with ifconfig <eth0> and <eth1> and cat /proc/net/bonding/bond0

Linux Bonding Mode 1 Active-Backup

1 Answers1