[cobbler] Cobbler uses DHCP instead of a static IP

Zack Perry zack.perry at sbcglobal.net
Thu Nov 29 05:18:31 UTC 2012


> 
> Hi there, thanks for the response.
> 
> > 0. Do you use ISC DHCP server, or the dnsmasq? Does
> cobbler manage it?
> 
> There is no DHCP server on the subnet in question (the
> network eth0 is plugged in to).  There _is_ a DHCP server on the 
> eth1 subnet (the net the system is supposed to boot from and use 
> for install).  This server is managed by Cobbler.

That's OK. When you do PXE network install, a DHCP server is a 
mandatory component. Once installed, the system can use a different
network interface for production.  This is fine.

> 
> > 1. Have you used cobbler system getks --name=... to
> check your rendered kickstart file? Do you see the desired IP
> in the rendered version?
> 
> Everything looks fine in here.  I see static network
> configurations being >'d in to sysconfig/network-scripts files.

OK.

> > 2. Have you used cobbler cobbler system dumpvars
> --name=... to examine all variables?
> 
> The only thing that looks weird in here is "owner_eth*" and
> "hostname_eth*" are set to the hostname of the copied system, 
> rather than the system I'm installing.  I don't know what these 
> variables do or how to set them so I'm not sure if it's a problem.

Not having the same environment, I am afraid that I can't be of much
help here. But...

> 
> > 3. Have you checked your installation log and see what
> > the actions have been taken for your installation?
> 
> I haven't gotten through the install process.  It stops
> and prompts for an address at the very first step.  I've tried 
> looking at the other consoles but there isn't much there.  It is 
> just setting up network cards and trying DHCP.

If your kickstart template has provided all necessary information,
then anaconda shouldn't prompt you for anything.  There are two ways
that you can do:

0. Use the kickstart logging option to log everything to a remote
   logging server
1. In /etc/cobbler/settings, turn on anamon, and use the anamon 
   snippets in the /var/lib/cobbler/snippets to help you get the
   installation log

Granted, the above logs won't appear until anaconda is started. So,
in case like this, I would use tcpdump to figure out what's going on.

> 
> > Typically, after the above four steps, and assuming for
> > 0, you have *really* acquainted yourself with the respective man
> > page of the two DHCP servers, you should be able to make a static
> > IP assignment for Red Hat alike systems without a hitch. 
> 
> I'm not sure what you mean.  I shouldn't _need_ a DHCP
> server, right?

During PXE installation, you do. After installation, if your nodes
use static IP addresses, then the DHCP server is out of the
picture.

> 
> > Worst comes to the worst, you have the cobbler built-in
> > configuration management features come to your rescue. I have 
> > found that the 'Template Files' attribute for both profile and 
> > system objects, together with the bundled download snippet, as 
> > the last, but very reliable, resort.  
> 
> I'm happy to look in to this as an option, but I'm not sure
> where to start.
> Any advice?

I would suggest you to get the PXE network install going without being
prompted for manual input first.  After that, if somehow your nodes
are still dependent on DHCP, then use the above suggestion. 

Reference: http://cobbler.github.com/manuals/2.2.3/5/3/1_-_Built-In_Configuration_Management.html

HTH

-- Zack


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