Tried over in /r/kvm, but no luck. Looking for some help to understand a Linux bridge for KVM guest forwarding.
Followed more guides than I can even remember and I have even tried creating a separate bridge with separate guest and host NICs and I am having the same issues. ARP tables on the guest and host seem to be working as expected, but any layer three traffic beyond the host fails. Pings to the host work perfectly, and from the host to the guest, but anything on the physical network fails. Configs below, I would appreciate any help. As well a couple guides I have used are below, they get me to this point, but don't explain troubleshooting L3 connectivity issues. CentOS7 host for what it is worth as well.
https://jamielinux.com/docs/libvirt-networking-handbook/bridged-network.html
http://www.ibm.com/support/knowledgecenter/linuxonibm/liaat/liaatkvmsecconfvlans.htm
[root@kvm01 ~]# cat /etc/sysconfig/network-scripts/ifcfg-eno16777984 DEVICE=eno16777984 ONBOOT=yes BRIDGE=br0 TYPE=Ethernet [root@kvm01 ~]# cat /etc/sysconfig/network-scripts/ifcfg-br0 TYPE=Bridge BRIDGE_PORTS=eno16777984 BOOTPROTO=static DEVICE=br0 ONBOOT=yes IPADDR="192.168.1.11" NETMASK="255.255.255.0" GATEWAY="192.168.1.1" DNS1="192.168.1.15" [root@kvm01 ~]# cat /etc/libvirt/qemu/networks/host-bridge.xml <network> <name>host-bridge</name> <uuid>7635d23b-433f-405a-8027-e314e53e8fd6</uuid> <forward mode='bridge'/> <bridge name='br0'/> </network> [root@kvm01 ~]# virsh net-list Name State Autostart Persistent ---------------------------------------------------------- host-bridge active yes yes [root@kvm01 ~]# cat /etc/libvirt/qemu/KVMPC01.xml | grep -B 2 -A 3 br0 <interface type='bridge'> <mac address='52:54:00:a0:02:d5'/> <source bridge='br0'/> <model type='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> [root@kvm01 ~]# brctl show bridge name bridge id STP enabled interfaces br0 8000.000c2980140a yes eno16777984 vnet0 virbr0 8000.000000000000 no [link] [comments]