Heres some background info. I'm running RH 8.0 on a 1ghz amd machine. I'm dual booting with RH, and XP. I have recently installed (for the second time) RH 8.0. Now my AMD board comes with an onboard ethernet card, but my ISP has provided me with one that I use. (since red hat dislikes onboard things). My ISP is Road Runner, and is cable.

The problem is that I cannot telnet into my machine. I can telnet into localhost, but when i try to telnet to the ip, i cannot establish a connection. One thing that bothers me, is that I have had the same IP address for 2 months, and is the same when I am in windows(66.8....) But when I boot into linux it changes (22.33......) I disabled what I thought was the onboard card after the install of red hat, (eth0) but I could be mistaken. Now in linux I can browse, get mail, chat ect. but I cannot telnet into my machine from another location. From my desktop I can telnet to localhost 23, or the ip address 23. I was planning on re-installing the system when I got home from work, but I would like to know what caused this. Also, here are some things I have done to the o/s after the install. I have stoped some services that I didn't think I needed. And changed port settings for telnet in etc/inetd.d/services (might have been etc/services) I'm not sure if any of those things could have caused the problem.

Thanks,
Digsby

Seems to me this isn't an ethernet problem like your title but more of a telnet problem. First thing you need to look at is, is telnet running ? What settings do you have for telnet, since you mentioned you changed the port setting ? If you changed the port setting, what port did you change it to and are you specifying that when trying to telnet into your box ?

Second, you might want to just blow over this whole telnet thing as its totally insecure. I'd suggest using ssh. www.openssh.org and its probably already on your Redhat install as well.

Well the changes I made to telnet was the port in services from 23, to 8080. I comented out web cache (which was also 8080). Telnet is running, and I tested this with a friend telneting to my machine. The thing that bothers me is the IP address changes when i move from windows to linux. In windows I have the same address I have had for about 2 weeks now (66.8....etc) but in linux it gives me an IP of 22.33...etc. These IP's do not change however. They are constant within that o/s. I have switched back and forth from windows to linux, and it never fails windows has the 66.8... and linux has the 22.33... I am new to linux, so maybe this is how it is? I have had RH 8.0 before though, and when I would switch between xp and linux, the ip addres would be the same no matter what o/s I was in. I would use ssh, but when I had my friend scan my IP address he could not find any open ports, but he could ping me. I am very confused.

Thanks,
Digsby

Well the IP change is occuring on how the server assigns the IP. I have DHCP for my connection on cable and I've kept the same IP for the past year and 4 months, but however if I change and make a direct connection besides my router, my IP will change, but then go back to my existing one I had before. I wouldn't worry about that, that is just how your ISP is assigning the IP with either different OS's.

But what happens if you try with the default port ? It could be that your ISP blocks port 8080 ? Have you tried any other ports ?

Ive tried alot of ports. My ISP doesn't block it because I have logged into it on port 8080, and 23, both of which do not work now. Does it make sense that they cange the ip when i do not have a router? I only have one machine connected to the cable. I was only concerned because before this install of linux, The ip did not change when i switched the o/s.

And your certain that you have a file telnet in your /etc/xinetd.d and it is enabled ? You mentioned something about /etc/inetd/services but I do know the configuration should be xinetd.

Also make sure the actual telnet server is installed. I believe you can find it on your redhat cd at /RedHat/RPMS/telnet-server-0.17-23.i386.rpm
You might have it enabled but it can't run til its installed. When your booting up, does it say telnet [ok] or something along those lines ? Is the process running at this time ?


But like I said, don't worry about the IP change, that shouldn't make a difference for your situation.

RoadRunner asigns the IP according to MAC address the fact that it changes IP address tells me that linux is using one mac address and windows is using another. You should be able to force windows to use the same adaptor. Also a cable modem will only reconize one MAC address at a time to prevent theft of signal so if it changes then you will need to reboot your modem. Hope this helps.

Sounds like a firewall is the problem. You can turn off iptables and then see if you can telnet into you PC.

Ok telnet is installed and running. The only thing I changed about that is the port it uses. There is no firewall running at this time. As the mac address goes, I dont want to force the change in windows due to the fact that the telnet server in windows works. I will reset the modem though and try that.

Thanks for all of the input and help,
Digsby