bond active-backup with arp-ip-target flapping

[Satish Patel]

I am running ubuntu 20.04 with following kernel and netplan version

# cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.1 LTS"

# uname -a
Linux ovn-lab 5.4.0-89-generic #100-Ubuntu SMP Fri Sep 24 14:50:10 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

netplan.io 0.102-0ubuntu1~20.04.2

This is my configuration

 bonds:
    bond0:
      dhcp4: no
      interfaces:
        - eno49
        - eno50
      parameters:
        mode: active-backup
        primary: eno49
        arp-ip-targets: [ 10.64.0.10, 10.64.0.11 ]
        arp-interval: 10
        arp-validate: active

When i shutdown upload switch port to simulate my issue during that time i have noticed bond start flapping between eno49 and eno50. sometime active slave is eno49 and in few minute eno50.

# cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: eno49 (primary_reselect always)
Currently Active Slave: eno49
MII Status: up
MII Polling Interval (ms): 0
Up Delay (ms): 0
Down Delay (ms): 0
Peer Notification Delay (ms): 0
ARP Polling Interval (ms): 10
ARP IP target/s (n.n.n.n form): 10.64.0.10, 10.64.0.11

Slave Interface: eno50
MII Status: up
Speed: 10000 Mbps
Duplex: full
Link Failure Count: 804
Permanent HW addr: 5c:b9:01:9d:ac:ad
Slave queue ID: 0

Slave Interface: eno49
MII Status: up
Speed: 10000 Mbps
Duplex: full
Link Failure Count: 1009
Permanent HW addr: 5c:b9:01:9d:ac:ac
Slave queue ID: 0