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I've been looking around all day and finally broke down and figured I'd have to ask a question of my own instead of leaching off the questions of others for info.
I just got a fresh install of RH9 on a p3 550 going and I can connect to the machine via my windows box with the local IP (192.168.1.100) but not the internet IP (for me to know)
I've setup a linux box the same way before except it had GUI and an XP install dual booted with it. SSH worked fine out of the box.
Things I've already done:
+Put 192.168.1.100 in the DMZ with my router. All routing is static, no DHCP used. I also tried forwarding port 22.
+Put security setting to no firewall during the install.
+Tried SSH from a computer outside of the region.
+nmapped for port 22, its open.
+Messed around with hosts(allow,deny) according to what others have tried, with no luck.
+Set the IP variable in /etc/ssh/sshd_config to the lan IP, and the inet IP.
+Probably more that I don't remember, please helpppppp!!!
Uhm, other than that... There is nothing in the /var/log/messages or secure files that have to do with unsuccesful ssh. I guess this tells me that its not even getting through to the box, but it worked exactly the same way on the previous dual boot box I setup.
Someone solve this and make me feel stupid, please.
The things you've done are not completely clear yet:
+Did you try to nmap from the Internet to your machine?
If you are able to see an open port 22 from the Internet, try to ssh from the Internet with a -v option to show some debug information. If you are not, this is most likely a router problem. Put some more information on what kind of Internet connection you have: ADSL Ethernet modem? Cable? What kind of modem?
A problem allways can be solved. It just takes some time. There's nothing stupid about that.
+Can you still do a "ssh localhost"?
+What kind IP variable did you try to set in /etc/ssh/sshd_config? It doesn't sound familiar to me.
A remote portscan not showing port 22 means SSH is not listening at all to the outside world. It indeed is not a routing problem cause the portscan works for the other services.
I hope you made sure along the way that ssh was running (ps aux| grep ssh)
Yea I can ssh localhost, however my problem just got funkier...
I thought earlier that it might be a problem like not getting any outside internet access at all, so I pinged google and it came back fine. However now (I think it might be new to the reinstall I did) I can't ping anything outside the network...
I just did a port scan with an outside the network machine and it came back with the same as the one I did on this machine (which is inside the network).
Okay, I don't bother anymore about the SSH settings. First things first. You have a problem with your network.
* Does "ifconfig" show all your network interfaces including lo?
* Can you ping your routers IP?
* Can you ping your other machines?
* Can you ping www.google.com's IP address: 18.104.22.168?
* Are there entries in /etc/resolv.conf?
* Does internetworking still work on the other machines?
* Are all machines wired only to the router, or are they interlinked as well?
* Does your router support NAT? If so, does it still have a NAT rule of forwarding port 22 to your Linux machine?
I had some entries in resolve.conf, going off others suggestions. I added 209.216.188.xxx (my IP) and my ISPs nameservers 22.214.171.124, 126.96.36.199. I removed my IP and restarted, nothing. I have now removed the nameservers, haven't restarted yet.
Google doesn't work:
connect: Network is unreachable
Pinging router works.
I have 2 nics in the machine, 1 isn't plugged in to anything though.
If you can ping from the other machines an address on the Internet (for instance Google), it may be just a routing problem on your Linux machine. If you want to access from your machine both your internal network and the Internet, you need to have a default gateway set to the router.
Check with "netstat -rn" your routing table. If it doesn't mention your router's IP address as gateway, that's the problem.
Add the router like this:
# route add default gw 10.0.0.138
Then try to ping the IP address of Google again. If it works, you want to set your router as gateway permanently. Add in /etc/sysconfig/network an entry like "GATEWAY=192.168.1.1" if 192.168.1.1 is your routers IP.