[CentOS-virt] Cannot get kvm guests to connect to network

Fri Oct 12 13:16:07 UTC 2012
James B. Byrne <byrnejb at harte-lyne.ca>

This cross-posted from the main Centos discussion list.

I installed a new CentOS-6.3 kvm guest on a recently provisioned kvm
host also running CentOS-6.3.  This guest will not connect to the
network and the host cannot connect to it via its public IP address. I
had previously installed a guest system on thst same kvm host using
the same ISO and that system connects to the network without problem.

I next created a third guest instance and this too does not connect
with either the kvm host or the gateway.

I have shutdown all the guests, restarted networking on the host and
restarted the gueests and the problem persists on the two most
recently added guests but does not happen on the first guest instance.


I have installed litterally dozens of kvm guests this past year and I
have never encountered this situation.  Has anyone else?  Does anyone
have any idea what might be going on?

ip addr
1: lo <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast
state UP qlen 1000
    link/ether 52:54:00:a0:26:47 brd ff:ff:ff:ff:ff:ff
    inet 216.185.71.243/24 brd 216.185.71.255 scope global eth0
    inet6 fe80::5054:ff:fea0:2647/64 scope link
       vaslid_lft forever preferred_lft forever

ip route
216.185.71.0/24 dev eth0  proto kernel  scope link  scr 216.185.71.243
169.254.0.0/16 dev eth0  scope link  metric 1002
default via 216.185.71.1 dev eth0

netstat -r
Kernel IP routing table
Destination    Gateway      Genmask        Flags  MSS Window  irtt Iface
216.185.71.0   *            255.255.255.0  U        0 0          0 eth0
link-local     *            255.255.0.0    U        0 0          0 eth0
default        216.185.71.1 0.0.0.0        UG       0 0          0 eth0

service iptables stop
.  .  .

ping 216.185.71.1
PING 216.185.71.1 (216.185.71.1) 56(84) bytes of data.
>From 216.185.71.243 icmp_seq=2 Destination Host Unreachable
>From 216.185.71.243 icmp_seq=3 Destination Host Unreachable
>From 216.185.71.243 icmp_seq=4 Destination Host Unreachable
^C


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