Recently I had to switch my Proxmox server which was using Linux bonds to using openvswitch. These are my notes:

Install openvswitch:

apt install openvswitch-switch

Configure openvswitch to bond interfaces and use VLANs using https://pve.proxmox.com/wiki/Open_vSwitch as an example:

allow-vmbr0 bond0
iface bond0 inet manual
	ovs_bonds enp4s0f0 eno1
	ovs_type OVSBond
	ovs_bridge vmbr0
	ovs_options bond_mode=active-backup

auto lo
iface lo inet loopback

iface eno1 inet manual

iface enp4s0f0 inet manual

allow-ovs vmbr0
iface vmbr0 inet manual
	ovs_type OVSBridge
	ovs_ports bond0 vlan50 vlan10

#Proxmox communication
allow-vmbr0 vlan50
iface vlan50 inet static
  ovs_type OVSIntPort
  ovs_bridge vmbr0
  ovs_options tag=50
  ovs_extra set interface ${IFACE} external-ids:iface-id=$(hostname -s)-${IFACE}-vif
  address 10.0.50.2
  netmask 255.255.255.0
  gateway 10.0.50.1

#Storage network
allow-vmbr0 vlan10
iface vlan10 inet static
  ovs_type OVSIntPort
  ovs_bridge vmbr0
  ovs_options tag=10
  ovs_extra set interface ${IFACE} external-ids:iface-id=$(hostname -s)-${IFACE}-vif
  address 192.168.10.2
  netmask 255.255.255.0

List active interface:

ovs-appctl bond/show bond0

Update 3/14/2020

I realized that openvswitch won’t fail back over to the original slave once it comes back online. I couldn’t for the life of me find the equivalent of bond-primary syntax for openvswitch; however I did find this command:

ovs-appctl list-commands

which reveals this command:

bond/set-active-slave port slave

So you can manually fallback using this command:

ovs-appctl bond/set-active-slave bond0 enp4s0f1