Hello, I have an environment with oVirt 4.3.8. All seems ok from a configuration point of view, but if I use OVN based interfaces on two VMs, they are not able to ping, both if I put them on the same host and if I put on different hosts. At this point they are both running on the same host and their only vnic is on ovn172 network (defined as 192.168.172.0/24). I have this manager # ovn-nbctl show switch fc2fc4e8-ff71-4ec3-ba03-536a870cd483 (ovirt-ovn192-1e252228-ade7-47c8-acda-5209be358fcf) switch 87012fa6-ffaa-4fb0-bd91-b3eb7c0a2fc1 (ovirt-ovn193-d43a7928-0dc8-49d3-8755-5d766dff821a) port 8141047d-10c0-41f6-bedc-130552a115ef addresses: ["00:1a:4a:17:01:54 dynamic"] port 90559419-cb8e-45ae-ad61-6c16c4aff598 addresses: ["00:1a:4a:17:01:52 dynamic"] port b3db190f-086a-4c79-99a0-77f811f66c80 addresses: ["00:1a:4a:17:01:53 dynamic"] switch 9e77163a-c4e4-4abf-a554-0388e6b5e4ce (ovirt-ovn172-4ac7ba24-aad5-432d-b1d2-672eaeea7d63) port 3641cae4-18df-4fba-a2bd-7b0c60a87162 addresses: ["00:1a:4a:19:01:59 dynamic"] port aaddc425-3a38-49bf-bfc7-9eaeab82906e addresses: ["00:1a:4a:19:01:58 dynamic"] The two macs correspond to what I see for VMs in web admin gui and at os level of the two VMs. On the host where VMs are running I have: # ovs-vsctl show f1a41e9c-16fb-4aa2-a386-2f366ade4d3c Bridge br-int fail_mode: secure Port "ovn-b8872a-0" Interface "ovn-b8872a-0" type: geneve options: {csum="true", key=flow, remote_ip="10.4.192.34"} Port br-int Interface br-int type: internal Port "vnet0" Interface "vnet0" Port "ovn-1dce5b-0" Interface "ovn-1dce5b-0" type: geneve options: {csum="true", key=flow, remote_ip="10.4.192.32"} Port "vnet1" Interface "vnet1" ovs_version: "2.11.0" So apparently I see the vnet0 and vnet1 ports associated with the two VMs How can I check more in depth the reason why they don't ping? Both VMs are CentOS 8.1 but I don't know if it is relevant. Thanks, Gianluca