<p><br>
On Oct 12, 2012 8:16 AM, "James B. Byrne" <<a href="mailto:byrnejb@harte-lyne.ca">byrnejb@harte-lyne.ca</a>> wrote:<br>
><br>
> This cross-posted from the main Centos discussion list.<br>
><br>
> I installed a new CentOS-6.3 kvm guest on a recently provisioned kvm<br>
> host also running CentOS-6.3. This guest will not connect to the<br>
> network and the host cannot connect to it via its public IP address. I<br>
> had previously installed a guest system on thst same kvm host using<br>
> the same ISO and that system connects to the network without problem.<br>
><br>
> I next created a third guest instance and this too does not connect<br>
> with either the kvm host or the gateway.<br>
><br>
> I have shutdown all the guests, restarted networking on the host and<br>
> restarted the gueests and the problem persists on the two most<br>
> recently added guests but does not happen on the first guest instance.<br>
><br>
><br>
> I have installed litterally dozens of kvm guests this past year and I<br>
> have never encountered this situation. Has anyone else? Does anyone<br>
> have any idea what might be going on?<br>
><br>
> ip addr<br>
> 1: lo <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN<br>
> link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00<br>
> inet <a href="http://127.0.0.1/8">127.0.0.1/8</a> scope host lo<br>
> inet6 ::1/128 scope host<br>
> 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast<br>
> state UP qlen 1000<br>
> link/ether 52:54:00:a0:26:47 brd ff:ff:ff:ff:ff:ff<br>
> inet <a href="http://216.185.71.243/24">216.185.71.243/24</a> brd 216.185.71.255 scope global eth0<br>
> inet6 fe80::5054:ff:fea0:2647/64 scope link<br>
> vaslid_lft forever preferred_lft forever<br>
><br>
> ip route<br>
> <a href="http://216.185.71.0/24">216.185.71.0/24</a> dev eth0 proto kernel scope link scr 216.185.71.243<br>
> <a href="http://169.254.0.0/16">169.254.0.0/16</a> dev eth0 scope link metric 1002<br>
> default via 216.185.71.1 dev eth0<br>
><br>
> netstat -r<br>
> Kernel IP routing table<br>
> Destination Gateway Genmask Flags MSS Window irtt Iface<br>
> 216.185.71.0 * 255.255.255.0 U 0 0 0 eth0<br>
> link-local * 255.255.0.0 U 0 0 0 eth0<br>
> default 216.185.71.1 0.0.0.0 UG 0 0 0 eth0<br>
><br>
> service iptables stop<br>
> . . .<br>
><br>
> ping 216.185.71.1<br>
> PING 216.185.71.1 (216.185.71.1) 56(84) bytes of data.<br>
> >From 216.185.71.243 icmp_seq=2 Destination Host Unreachable<br>
> >From 216.185.71.243 icmp_seq=3 Destination Host Unreachable<br>
> >From 216.185.71.243 icmp_seq=4 Destination Host Unreachable<br>
> ^C<br>
><br>
><br>
> --<br>
> *** E-Mail is NOT a SECURE channel ***<br>
> James B. Byrne mailto:<a href="mailto:ByrneJB@Harte-Lyne.ca">ByrneJB@Harte-Lyne.ca</a><br>
> Harte & Lyne Limited <a href="http://www.harte-lyne.ca">http://www.harte-lyne.ca</a><br>
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><br>
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<p>Did you configure your KVM host's public interface with a bridge? what is the output of 'brctl show'?</p>
<p>Also Ive run into VM host issues on corporate networks where port security limits number of unique MAC addresses able to communicate on one physical switch port.</p>
<p>- Trey</p>