Periodic packet loss


New Member
May 31, 2021
Hi all! I have 2 standalone servers with lastest proxmox ve. Each server has two ethernet adapters, they bonded and bridged via openvSwitch with config:

auto eno1np0

iface eno1np0 inet manual
auto eno2np1

iface eno2np1 inet manual
auto bond0

iface bond0 inet manual
        ovs_bonds eno1np0 eno2np1
        ovs_type OVSBond
        ovs_bridge vmbr0
        ovs_options bond_mode=active-backup

auto vmbr0

iface vmbr0 inet static
        address 10.X.X.X/24
        gateway 10.X.X.254
        ovs_type OVSBridge
        ovs_ports bond0

ovs-appctl bond/show bond0

---- bond0 ----
bond_mode: active-backup
bond may use recirculation: no, Recirc-ID : -1
bond-hash-basis: 0
updelay: 0 ms
downdelay: 0 ms
lacp_status: off
lacp_fallback_ab: false
active slave mac: ac:1f:6b:e7:a1:73(eno2np1)

slave eno1np0: enabled
  may_enable: true

slave eno2np1: enabled
  active slave
  may_enable: true

ping stats from srv2 to gateway
--- 10.X.X.254 ping statistics ---
134 packets transmitted, 130 received, 2.98507% packet loss, time 306ms
rtt min/avg/max/mdev = 0.336/0.512/1.118/0.128 ms

ping stats from srv1 to gateway
932 packets transmitted, 899 received, 3.54077% packet loss, time 1879ms
rtt min/avg/max/mdev = 0.311/0.518/8.792/0.304 ms

if shutdown one port on the swith, no packet loss, works fine!
Switch periodic report:
%SW_MATM-4-MACFLAP_NOTIF: Host ac1f.6be7.a21c in vlan 2009 is flapping between port Gi2/0/9 and port Gi1/0/9
%SW_MATM-4-MACFLAP_NOTIF: Host ac1f.6be7.a172 in vlan 2009 is flapping between port Gi1/0/1 and port Gi2/0/1

other servers on same switches works on other operating system - no problems.
VMs one servers use vmbr0 for connection to network with vlan tagging.

Please tell any idea for debug \ fix packet loss. I am confused(


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Last edited:


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