Hi folks, I'm in the process of upgrading to 3.6, and have encountered a new error message. I understand the error, and how to fix it. My question is, can fixing it affect production VM traffic? I don't think so, but I'd appreciate confirmation from someone who really knows, please. Description of what I am doing: I've upgraded hosted-engine, and am now upgrading the first hypervisor node. My method, which may be outdated, is: have no VMs running on the host, I drop it out of the cluster, do yum updates & reboots, then add the host back to the cluster when it's ready. When I add the host to the cluster, I get this error message: Failed to configure management network on host bl05. Host bl05 has an interface eth0.20 for the management network configuration with VLAN-ID (20), which is different from data-center definition (none). I know what this means, and will explain it for the benefit of others. It means that: * the ovirtmgmt bridge on the host is attached to a VLAN 20 subinterface. That is by design; it is correct. * However, in Data Center > Networks definition of ovirtmgmt, there is no VLAN tag defined, so my hosted-engine believes that ovirtmgmt should go into in VLAN 1. Also, for completeness: * there is PVID 20 on the adjacent switchport, which means "untagged ingress traffic should be tagged into VLAN 20". This is why my ovirtmgmt network has been working. * I am grateful for the error message now appearing, as it shows me where I have misconfigured this a long time ago. So. To fix this, I need to add VLAN 20 tag in ovirtmgmt in Data Center > Networks. My question: If I add the VLAN 20 tag to ovirtmgmt in Data Center > Networks, is there any possibility of breaking traffic (or VMs) on other (production) VLANs? From my general knowledge, I cannot see that would be the case, but I would be grateful for an informed opinion from someone who has tried it before please. Best regards to all, Garry * *