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.