I don't know if doing something in a %pre script is appropriate for 
your situation, but even if it is, "chmod a-w /etc/resolv.conf" might not 
prevent NetworkManager from changing the file.  I believe NetworkManager 
runs as root, and if as root you try such a chmod command on a file, 
you'll find that root has no problem changing the file.  But root doing 
"chattr +i /etc/resolv.conf" should protect resolv.conf.  After that 
chattr command even root can't change resolv.conf without first doing 
"chattr -i /etc/resolv.conf".

Steven Yellin

On Thu, 7 Apr 2011, Ahmed El Zein wrote:

> Nico,
> Thanks for that. I don't have NetworkManger installed in by base system.
> My problem is how do I stop NetworkManger running during the anaconda
> install process while kickstarting? From what I can gather everything
> works fine until it starts. one it starts it ruins the /etc/resolv.conf
> file and all my %post scripts fail.
>
> can I do something in a %pre script that will prevent NetworkManger from
> editing anything. maybe a "chmod a-w /etc/resolv.conf"?
>
> Thanks,
> Ahmed
>
>
>
>
> On Thu, 2011-04-07 at 00:07 -0400, Nico Kadel-Garcia wrote:
>> On Wed, Apr 6, 2011 at 2:50 AM, Ahmed El Zein <[log in to unmask]> wrote:
>>
>>> I am looking at the logs and the only network related log that coincides
>>> with the resolv.conf file changing is:
>>> <29> Arp 6 06:40:49 NetworkManager[542]:    ifcfg-rh:
>>> updating /etc/sysconfig/network-scripts/ifcfg-eth0
>>>
>>> at that point /etc/sysconfig/network-scripts/ifcfg-eth0 changes and gets
>>> an NM_CONTROLLED="yes" added to it and the /etc/resolv.conf file is
>>> replaced with the single lined one.
>>
>> NetworkManager, frankly, has no use on a typical server. Its dynamic
>> manipulations of network configuration are unpredictable, unintuitive,
>> and far more suited to a laptop or traveling desktop in an environment
>> where upstream DHCP is reliably configured. It is a complex and
>> powerful tool that *STILL* has no way to configure pair-bonding,
>> 'bridged' connections for KVM supporting hosts, or DHCP client
>> configuration with client identifiers except to use a text editor and
>> turn off NetworkManager by one means or another. It's one of the
>> upstream vendors least useful development efforts.
>>
>> Unfortunately, we're now pretty much stuck with it, due to all the
>> recent system dependencies on it. Ripping it out by the roots became
>> infeasible with Scientific :Linux 6. Fortunately, pre-configuring
>> 'NM_CONTROLLED=no' is a new capability, and doing so early in the
>> kickstart '%post' scripts seems to be very helpful in preventing such
>> issues. In syntax:
>>
>>       grep -q ^NM_CONTROLLED= [filename] || \
>>            echo 'NM_CONTROLLED=no' >> [filename]
>>       sed -i 's/NM_CONTROLLED=.*/NM_CONTROLLED=no/g' [filename]
>>
>> Deducing the files to do this to is a bit more awkward, since you
>> don't want to touch '.bak' files or '~' files, but there are functions
>> to do that already available in the /etc/sysconfig/network-scripts/
>> utiliti4es. Do you need help with that?
>
> -- 
> Ahmed H. El Zein
> Data Services Specialist
> ANU Supercomputer Facility
> Room 315, Leonard Huxley Building (#56), Mills Road
> The Australian National University
> Canberra ACT 0200 Australia
>
> T: +61 2 6125 0539
> F: +61 2 6125 8199
> M: +61 4 4913 5073
> W: http://anusf.anu.edu.au/
>
> CRICOS Provider #00120C
> --------------------------------------------
>