I have a strange networking problem with Windows 2008 server R2, running as guest under KVM-Qemu host. Host is CentOS 6.3 x86_64. It's network settings:
# cat /etc/sysconfig/network-scripts/ifcfg-br0 DEVICE=br0 BOOTPROTO=static BROADCAST=xx.xx.xx.63 IPADDR=xx.xx.xx.4 NETMASK=255.255.255.192 NETWORK=xx.xx.xx.0 ONBOOT=yes TYPE=Bridge # cat /etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE=eth0 HWADDR=xx:xx:xx:xx:xx:xx ONBOOT=yes BRIDGE=br0 IPV6INIT=yes IPV6_AUTOCONF=yes # cat /etc/sysconfig/network NETWORKING=yes NETWORKING_IPV6=no HOSTNAME=my.hostname GATEWAY=xx.xx.xx.1 # cat /etc/sysctl net.ipv4.ip_forward = 1 # tried to set it to 0 without any changes net.ipv4.conf.default.rp_filter = 1 # tried to set it to 0 without any changes net.ipv4.conf.default.accept_source_route = 0 # tried to set it to 1 without any changes kernel.sysrq = 0 kernel.core_uses_pid = 1 net.ipv4.tcp_syncookies = 1 net.bridge.bridge-nf-call-ip6tables = 0 net.bridge.bridge-nf-call-iptables = 0 net.bridge.bridge-nf-call-arptables = 0 kernel.msgmnb = 65536 kernel.msgmax = 65536 kernel.shmmax = 68719476736 kernel.shmall = 4294967296 # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface xx.xx.xx.0 0.0.0.0 255.255.255.192 U 0 0 0 br0 169.254.0.0 0.0.0.0 255.255.0.0 U 1004 0 0 br0 0.0.0.0 xx.xx.xx.1 0.0.0.0 UG 0 0 0 br0
Node IP is xx.xx.xx.4, guest IP is xx.xx.xx.24, both host and guest is in the same network (/26). There are several linux guest running fine on the node (centos, debian, ubuntu, arch), and even Windows 2003 x86 also running fine. But Win2008 does not. I wonder, what's the difference. From Win2008 guest I can ping nothing: neither gateway, nor any other IP, even they are in the same subnet. From outside I also cannot ping guest. Almost. If I ping it from another server in same subnet, it's barely pinging, losing more than 90% packets. Firewall on the guest is completely off. Tried to set up network manually as well as via DHCP without success (BTW, DHCP set up network settings correctly). I suspect that is a kind of routing problem, but I spent whole day and still cannot figure it out. I would be appreciate for any help.