Paul,

On Thu, Mar 17, 2016 at 5:47 PM, Digimer <lists@alteeve.ca> wrote:

On 17/03/16 04:47 PM, paul.greene.va@verizon.net wrote:
> Thanks, I followed the 2nd article, and it got the existing virtual
> machines communicating with each other.

Right, so your VMs are on the same bridge group now (at Layer2 of OSI).

>
> However, any new virtual machines I created after making the changes
> can't communicate with anything, they can't even get out to the
> internet, even if I manually set the IP address info. Any suggestions on
> that?
>
> Paul

Have you verified connectivity to the VMs' default gateway?

Does the ARP (address resolution protocol) process succeed?

arp -a | grep <Default_Gateway_IP_here>

http://linux-ip.net/html/ether-arp.html

You may not have a NIC connected to your physical network in that bridge group.

If so you need to modify your network-scripts to make that happen automatically on boot.

You do not necessarily need an IP address on your bridge interface unless the VM host is acting as a router (default gateway).

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Deployment_Guide/s2-networkscripts-interfaces_network-bridge.html

Here's an example:

~]# cat /etc/sysconfig/network-scripts/ifcfg-XX_br0

DEVICE=XX_br0

TYPE=Bridge

BOOTPROTO=static

ONBOOT=yes

DELAY=0

NM_CONTROLLED=no

You can temporarily add an interface to the bridge group for testing purposes though.

brctl addif <bridge> <interface>

http://www.tldp.org/HOWTO/BRIDGE-STP-HOWTO/set-up-the-bridge.html

Check that they're using your static bridge. 'virsh dumpxml <vm>' will
have a section like:

====
<interface type='network'>
<mac address='52:54:00:71:20:fa'/>
<source network='bcn_bridge1' bridge='bcn_bridge1'/>
<target dev='vnet2'/>
<model type='e1000'/>
<alias name='net2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05'
function='0x0'/>
</interface>
====

That tells you that the interface is MAC '52:54:00:71:20:fa' is "plugged
in" to the bridge 'bcn_bridge1'. If that doesn't connect to the right
bridge, then you need to change it (virt-manager has a simple to use GUI
for this, or you can use 'virsh edit <vm>' if you're comfortable editing
XML).

An additional command to run to verify your Ethernet bridge(s) operation is:

brctl show

brctl show <bridge>

~]# brctl show XX_br0

bridge name bridge id STP enabled interfaces

XX_br0 8000.00151713fdbc no p1p1

vnet0

vnet1

vnet11

vnet12

vnet13

vnet19

vnet2

vnet4

vnet6

vnet7

---~~.~~---
Mike
// SilverTip257 //