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View Full Version : [SOLVED] Please Help - Weird network problem



bduvall3
April 8th, 2010, 05:11 PM
Ok, so during the past few weeks, I managed to put together an Ubuntu Server system.
P4 2.4, 2gb PC3200, 40gb /dev/sda (Karmic), 80gb /dev/sdb <-- ntfs mounted in /media/store.

Samba is up and running.
I can SSH in from work, which I happen to be doing right now.
Need to setup VPN server on it <-- I know what I need to do for this.

Here's the problem I'm having. Like I said, I'm currently on the system (Putty'd in from My Office), but when I run sudo apt-get update (sudo apt-get install pptpd is how I noticed it), it's not going out and pinging sites.

I know that network is up and running, but I can't figure out why Port 80 isn't working right. BTW - This is an intermittent problem. Sometimes I reboot, and it's fine.

Any ideas?

VernieR
April 8th, 2010, 05:43 PM
Could it be a DNS issue?

cdenley
April 8th, 2010, 06:44 PM
So you can't connect to any web server?


host ubuntu.com
nc -z -v -w 5 ubuntu.com 80
nc -z -v -w 5 91.189.94.156 80
cat /etc/resolv.conf

bduvall3
April 8th, 2010, 06:54 PM
So you can't connect to any web server?


host ubuntu.com
nc -z -v -w 5 ubuntu.com 80
nc -z -v -w 5 91.189.94.156 80
cat /etc/resolv.conf


When I run the last two of those commands, I get

nc -z -v -w 5 91.189.94.156 80
91.189.94.156: inverse host lookup failed: Host name lookup failure
(UNKNOWN) [91.189.94.156] 80 (www) open

and


cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN

One more thing, I have a webserver up and running on this machine, and I can get to the site.

cdenley
April 8th, 2010, 07:05 PM
The output you actually posted indicates you don't have any DNS server configured. However, if that were the case, then you would get output like


cdenley@ubuntu:~$ host ubuntu.com
Host ubuntu.com not found: 3(NXDOMAIN)
cdenley@ubuntu:~$ nc -z -v -w 5 ubuntu.com 80
ubuntu.com: forward host lookup failed: Unknown host

I don't think you posted output from the first command, and you seem to suggest that the second command results in an open connection.

bduvall3
April 8th, 2010, 08:05 PM
Sorry about that.
Reply to first test looks as follows.

bill@HomeServer:/media$ host ubuntu.com
;; connection timed out; no servers could be reached


EDIT:
I got it. Reset my DNS.
Sorry for the linuxnewbie questions, and thanks for the help.

cdenley
April 8th, 2010, 08:09 PM
Sorry about that.
Reply to first test looks as follows.

bill@HomeServer:/media$ host ubuntu.com
;; connection timed out; no servers could be reached


Well then I assume I was correct about the second command as well?

Anyway, you have to configure DNS servers so your server can resolve domain names such as ubuntu.com to an IP address.

/etc/resolv.conf


nameserver 208.67.222.222
nameserver 208.67.220.220

bduvall3
April 9th, 2010, 02:02 PM
Yep, that's what I did.
Thanks again for all the help.

Iowan
April 9th, 2010, 11:19 PM
[SOLVED] (https://wiki.ubuntu.com/UnansweredPostsTeam/SolvedThreads)? :)