[CentOS] Centos 6 - Networking: Some Queries -- GURUS HELP PL

Mon Jun 4 17:14:50 UTC 2012
Gordon Messmer <yinyang at eburg.com>

On 06/01/2012 02:38 AM, Sanjay Arora wrote:
> With NM_Controlled=No in the ifcfg file, NM applet shows "Not Managed", so
> the ifcfg file is being read. What is the extent of interaction of
> NetworkManager with ifcfg files is unknown....very little information on
> the net. Seems Network Manager is still mostly unplublished compared to
> other utilities. Any pointers to literature on this or macro architecture
> of NM would be appreciated, as Google is not throwing up the right results.

You're right.  Documentation is sparse.
$ man NetworkManager
$ man NetworkManager.conf
less /usr/share/doc/initscripts-*/sysconfig.txt

> On a separate note however, I'd still like to know how to use a bridge to
> route packets between two networks.....say network card having
> address... and a kvm based virtual network say
> to use this device for Internet access (through
> router
> using a bridge? How to do it?

If your networks are on different IPv4 broadcast domains (as you 
describe), you don't want a bridge.

If you want bridged networking with KVM, your guests will be on the same 
network as the host.  They'll use your existing DHCP services and 
routing.  They can be configured according to this document:

That configuration used to be reflected here:
...but someone went and put in some really braindamaged instructions. 
That should be fixed or removed.