On 23.12.2015 03:56, Phill Edwards wrote: > I have been running KVM on a CentOS 7.1 host for a few months. I have one > "main" host server plus a "backup" host server. Some time ago everything > was running fine on "main", but all of a sudden the server became > non-contactable on it's network interface. I could no longer SSH in and > therefore couldn't run virt-manager. I don't know what caused this and I > had to bring all the VMs up on "backup" and they've been running OK there > ever since. > > Over the last few days I've rebuilt "main" and again all was going well and > I migrated 4 of the 5 VMs back onto it. Then this morning I came to set up > the final VM on "main" which is a Sophos firewall machine with 3 NICs (I > have 3 physical NICs). Nothing uses 2 of the 3 NICs except the Sophos VM. I > unplugged one of the ethernet cables from "backup" and plugged it into the > 3rd NIC on "main" and all of a sudden "main" froze and again all network > connectivity was lost. I rebooted it but the problem still remains that > it's not contactable over the network and is therefore totally > non-functional. When I log in at the console and run "ip a" I can see > various network interfaces including br0 with the expected IP address - so > it looks like it's got network connectivity but it hasn't. Sounds like a HW problem to me. guest should not freeze when you (un-)plug a cable. Can you bring down a firewall for a while and see if that helps? Plenty of connectivity issues are caused by firewalls. It that won't help I suspect clashing subnets/routes. Michal _______________________________________________ libvirt-users mailing list libvirt-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvirt-users
