Can't see ADSL modem

[Timothy Murphy]

Marko Vojinovic wrote:

>> I have a small mystery on my home network.
...
>> The CentOS-6.2 machine does not get any response to pings
>> from the modem, but is able to ping sites beyond the modem.
>> 
>> Could some knowledgeable soul suggest a reason for this?
> 
> Are you sure the problem is with the CentOS machine and not the router
> itself?
...
> OTOH, if CentOS still doesn't work, then it's most probably the firewall
> --- either the CentOS firewall or the router firewall. Check them both for
> dropping ICMP packets.
> 
> I cannot think of any other problem. Can CentOS ping other machines on
> your LAN?

Thanks for all the responses.

I have to confess that my error was probably at kindergarten level ...
The modem is at 192.168.1.254 ,
while my LAN is 192.168.2.0 , which the computer accesses through eth1 .

I found (from "route") that this computer was trying to send 
packets for the modem through eth0, to which nothing was connected.
After I ran
	[tim at grover ~]$ sudo ifconfig eth0 down
I was able to access the modem.

I looked at /etc/sysconfig/network-scripts/ifcfg-eth0
and I saw that "ONBOOT=yes" was set.
(I had copied this from my working server.)

I sort of thought that this would not be activated
unless something was connected to the ethernet socket ...

	


-- 
Timothy Murphy  
e-mail: gayleard /at/ eircom.net
tel: +353-86-2336090, +353-1-2842366
s-mail: School of Mathematics, Trinity College Dublin