[CentOS] Cannot get kvm guests to connect to network

Thu Oct 11 21:12:02 UTC 2012
James B. Byrne <byrnejb at harte-lyne.ca>

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 isntance and this too does not connect
with either the kvm host or the gateway.  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 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 brd scope global eth0
    inet6 fe80::5054:ff:fea0:2647/64 scope link
       vaslid_lft forever preferred_lft forever

ip route dev eth0  proto kernel  scope link  scr dev eth0  scope link  metric 1002
default via dev eth0

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

service iptables stop
.  .  .

PING ( 56(84) bytes of data.
>From icmp_seq=2 Destination Host Unreachable
>From icmp_seq=3 Destination Host Unreachable
>From icmp_seq=4 Destination Host Unreachable

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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
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