Re: Fedora 9 NetworkManager

[Dan Williams <dcbw redhat com>]

On Thu, 2008-04-24 at 15:25 -0400, Gene Poole wrote:
> I've just installed the Preview of Fedora 9 on a desktop scale PC that was
> previously running Fedora 8.  This desktop PC utilizes a wired network
> ONLY.
> 
> During the install I answered all of the network questions as was expected
> (i.e. Are we to use DHCP or Static - I picked static etc.) including the
> DNS entries, Gateway entry.  All of the network worked until I booted after
> applying 652 updates (su - root;  yum -y update).  After that reboot I
> could only reach locations that were defined in my hosts file.  This
> pointed me to look at resolv.conf and alas there were no entries in
> resolv.conf only the message '# generated by NetworkManager, do not edit!'.
> I listened to that message as issued the system-config-network command and
> proceeded to update the DNS entries, performed a save, and then issued the
> following 2 commands:  /etc/init.d/network stop  then  /etc/init.d/network
> start.  After doing that I saw that the DNS were once again empty.  I
> 'corrected' this mess by starting webmin and stopping NetworkManager and
> NetworkManager Dispatcher and changing the parameter so they would not
> start at boot.  Once again did a system-config-network updating the DNS
> entries.  Restarted the network and now all is well.
> 
> My questions are:
>    Why is Network Manager messing with my wired network?

Because NetworkManager is the default on Fedora 9 and later.

>    If Network Manager has been updated so that it will work with a wired
>    network, must it be DHCP?

It should work with a wired network.  First, when you edited the
configuration with system-config-network, make sure that the 'Controlled
by NetworkManager' checkbox is checked.  System-config-network used to
mess that setting up if the ifcfg file didn't have an NM_CONTROLLED
setting, it would default to NO.

Second, you'll want to put:

DNS1=xxx.xxx.xxx.xxx
DNS2=xxx.xxx.xxx.xxx

into your /etc/sysconfig/network-scripts/ifcfg-eth0 file.  The problem
is that that s-c-n edits /etc/resolv.conf, but /etc/resolv.conf is the
composite of _all_ connections, and thus gets overwritten whenever
connections change.  Putting the DNS information into the ifcfg file
itself guarantees that you'll always get the right DHCP information.

If you could attach your /etc/sysconfig/network-scripts/ifcfg-eth0 file,
that would help greatly in figuring out what's going on.

>    And maybe this is a Fedora question, but why can't I chose if I want
>    Network Manager to do my network configuration?

You can choose; though I'd like to try to debug why it's not working for
you first.  If you want, you can '/sbin/chkconfig NetworkManager off'
and '/sbin/chkconfig network on'.

Cheers,
Dan