[vox-tech] Network Configurator

[Jeff Newmiller]

On Sun, 20 Jan 2002, Eric C Moloy wrote:

> 
> Hello,
> 
> This message is a follow up to an earlier message in Vol 1 #69 about not
> being able to access the network.

Many of us don't receive the mailing list in digest form. Dates are
probably more generally applicable for references.

>  The network card has been replaced, and
> Red Hat recognizes and installs the new eth0 device.  I am still unable to
> connect, however.  The following are the current settings in Network
> Configurator"
> 
> under the 'names' tab
> host name: 'computername'
> domain: engr.ucdavis.edu
> name servers: 169.237.1.250
> name servers: 169.237.250.250
> 

You may have boxed yourself into needing people who not only use redhat
but also use its network configurator by not telling us what the labels
were for each of these values under each "tab" below.  I have some
guesses, but I almost deleted this because I don't like to read so much
between the lines.

> under the 'hosts' tab
> 169.237.204.XXX, computername.engr.ucdavis.edu

I can guess that this is assigning your computer an ip address.

> 
> under the 'interfaces' tab
> lo, 127.0.0.1, none, yes, active
> eth0, 169.237.204.XXX, none, yes, active

I can guess that this is assigning ip numbers to interfaces, but I am not
sure what the "none" and "yes" are about.

> under the 'names' tab
> eth0, 169.237.204.0, 255.255.255.0, 169.237.204.254

"names"?

looks kind of like "routes" to me.  And if so, I suspect that the
"169...254" should not be there because that would be saying packets have 
to get to 169.237.204.254 before they can reach any other ip addresses on 
the 169.237.204.0/255.255.255.0 network, which is a kind of
chicken-and-egg problem that computers aren't good at figuring out.  The
truth is that eth0 is directly connected to 169.237.204.0/255.255.255.0,
so no gateway is needed for that network.

> The addresses, as far as IP, DNS, etc are all correct and functional.

Coming from someone whose system doesn't work, this is not worth
much.  If you want to assure us of this, describe why you know this to be
true, rather than stating it so baldly.

> Thanks for your help.

You are welcome.  Sorry to be so fussy, but it is important to be as
precise as possible about your observations, because those who help you
may solve problems differently than you do.

Anyway, what I don't see is anything that looks like a _default_ gateway.

If you go to the shell prompt as root and type "route -n" you should get
something like:

 Kernel IP routing table
 Destination   Gateway         Genmask        Flags Metric Ref  Use Iface
 169.237.204.0 0.0.0.0         255.255.255.0  U     0      0    0   eth0
 0.0.0.0       169.237.204.254 0.0.0.0        UG    0      0    0   eth0

The second entry means that anything that doesn't match the first entry
should be routed to the gateway, which will figure out where it should go
from there.

So... you might want to double check your "names" tab (routes) and make
changes there, or find out where in the /etc directory that your network
configuration files are and make the changes there.

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