problems with NIC/connectivity 2

[wolf2x]

I installed Red Hat 8.0 with no problems. I set up the ip address and gateway correctly but I can't ping anything other than the local machine (and localhost).

For example, internal network is 192.168.0.x with subnet 255.255.255.0. On this machine I set it's ip as 192.168.0.12 sub 255.255.255.0. I've checked and double-checked the cable ip address settings but I still can't connect to anything. BTW, firewall on the local machine has been disabled.

The lights on the NIC and on the hub's port are lit up.

Any insight on how to troubleshoot this?

Thanks in advance

 

[John Lewis]

. . . but I can't ping anything

Sure you can! You can ping anything, and it will (almost) always work. Might not give you what you want, but you can ping.

So . . . How are you pinging? Are you using the other computer's name or IP? What is the IP of the other machine? And most importantly, what message do you get from ping?

 

[wolf2x]

Well, I "try" to ping several computers by IP address (i.e. 192.168.0.205, 192.168.0.10, etc).

The message that I receive is "Destination host unreachable".

I checked route and it didn't have anything for the default route. This is the command that I used to try to add it:
"route add default gw 192.168.0.10 eth0". Do I need anything else to make it persistent?

 

[pupu]

I suggest:

less /var/log/messages and check for 'strange' messages

ifconfig

arp -an and see if there are at least some MACs

double-check routes (netstat -rn)

try another cable/switch/hub

If everything fails, try to post outputs from above commands here, we will take a look at them.

 

[wolf2x]

nothing strange in the messages log...after I added the default route, netstat -rn looks fine....but, I tried to ping the gateway (192.168.0.10)but it didnt work, and then checked arp -an and I got: &quot;? (192.168.0.10) at <incomplete> on eth0&quot;. So, no MACs are listed. I get the same message if I try to ping other IPs and check arp -rn.

 

[Norwich]

It could be a full/half duplex mode issue - a NIC in half duplex mode is for shared media (hubs etc). Full duplex is a point to point implementation and needs a dedicated switched port (or a crossover cable between two ful duplex machines).

Check the logs again to see if it is running improperly (for your setup) in full duplex mode.

Forcing duplex modes is dependent upon the card (I think).

 

[pupu]

Looks like hw, not sw problem to me. Try another cable/hub/hub port/card.

 

[wolf2x]

Thanks for your guys help. I gave both of you a star because both led me to solving it.

Plugged it into the hub, running ethereal I didn't see ANY traffic (tried different ports and a different card). I plugged the machine into our router and was able to catch all traffic. I just needed to adjust the duplex on the nic.

Thanks again!