Problem accessing external IPs

kevin_5050 · 02-06-2001, 04:59 AM

I'm using RH7. I have a problem accessing our mail server which has an external IP. Had no such problems when I assigned it an internal IP. Anyone else have this problem.

mjakob · 02-06-2001, 05:44 PM

Hmm. Could use a little more info about that. How many PCs do you have? Do you have a firewall between you and your mail server? Is the firewall and the mail server the same machine?

kevin_5050 · 02-06-2001, 10:17 PM

I'm assigned an IP using dhcp. I'm able to access the mail server from windows, but can't access it when I boot up in linux.

We have 100+ pcs on the network. Yes there is a firewall b/w my linux m/c and the mail server. We are using ipchains.
The firewall is not the same m/c as the mail server.
Our main server has IP - 192.168.1.2 and acts as the firewall. The mail server is outside the firewall. I tried assigning an IP 192.168.1.1 and it worked fine

Thanks,
Shankar

mjakob · 02-06-2001, 11:04 PM

If your PC works with Windows but not when you load Linux on it, then that pretty much limits it to the Linux configuration on the PC. The first thing that I would check is that your Linux PC is picking up the proper gateway address from DHCP and not using something that is written in a file somewhere instead. Check /etc/sysconfig/network and see if there is a gateway set there. Also check /etc/sysconfig/network-scripts/ifcfg-eth0 to make sure that DHCP is enabled. Let me know if that helps....

-Mark

kevin_5050 · 02-08-2001, 02:53 AM

DHCP is configured ok. I tried a route -n and the gateway is 192.168.1.2 which is correct. What else should I check.

Thanks,
Shankar

mjakob · 02-08-2001, 07:48 AM

Hmm, I'm running out of ideas here. The last thing I can think of would be a DNS problem. Look at what your PC is using for a name server in windows and make sure it's the same in Linux.

Maybe someone else can shed some light here. I must be missing something.

--Sorry!
-Mark

Mike_the_Man · 02-08-2001, 08:42 AM

This is really odd. The only thing i can think of is to run an ifconfig -a to make sure that all your interfaces are plumbed and enabled.

mjakob · 02-08-2001, 08:46 AM

The only thing being odd is that it works with windows, but not with Linux. To me, this means the problem is with the PC and not the firewall...