Re: Problem with DHCP, /etc/hosts and GNOME

[Keven Ring <keven mitre org>]

Rick Stevens wrote:

> Keven Ring wrote:
>
> > William Hooper wrote:
> >
> > > Satish Balay said:
> > >
> > >  
> > >
> > > > Ah.. I interptered it as - an option to dhcp-clinet (not server) to
> > > > ignore what dhcp server says - and use the provided value as the
> > > > hostname. Perhpas there should be some other option for this
> > > > functionality? (RFE)
> > > >
> > > > I don't like hostname changing (when you move laptop between networks)
> > > > - this changes xauth which messes up everything else..
> > > >   
> > >
> > >
> > >
> > > A quick browse through the networking scripts suggests that the 
> > > hostname
> > > will only change if it is "localhost".  I haven't looked too hard 
> > > though. I know that I don't have a problem with my laptop, which I 
> > > set the
> > > hostname on during install (but that was with RHL 9 and an upgrade to
> > > FC1).  It may be more of a case of the DHCP servers I'm using not 
> > > trying
> > > to change the hostname, though.
> > >
> > >
> > >  
> > It's in the /etc/sysconfig/network-scripts/network-functions script.  
> > There is a function called need_hostname().
> >
> > Returns 0 if the current hostname is "localhost", 
> > "localhost.localdomain" or "(none)".  Returns 1 otherwise.  This 
> > function is called in the /etc/sysconfig/network-scripts/ifup 
> > script.  However, again, just like everything else, just because the 
> > DHCP client *requests* a hostname, does not mean that the DHCP server 
> > is obliged to hand one back...
>
>
> And you're not "obligated" to accept it.  You can set
>
>     supersede host-name "your-host-name"
>
> in your /etc/dhclient/dhclient.conf file to override whatever the DHCP
> server gives you.  see "dhclient.conf(5)" and "dhcp-options(5)" for
> info.
Of course, if you tell the DHCP server what you want your hostname to 
be, *and* ask for the DHCP server to provide one back to you, *and* 
disregard the hostname that the DHCP server sends back, then you have an 
awfully friendly system... :)

DHCP Client:  Please set my host name to xxx.yyy.zzz.
DHCP Server:  No chance.  Your host name is aaa.bbb.ccc
DHCP Client:  Screw you.  I'm setting my hostname to mmm.nnn.ooo

Fine.  Is everyone happy now?

--
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