LinuxQuestions.org
Help answer threads with 0 replies.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices


Reply
  Search this Thread
Old 12-11-2014, 07:10 AM   #1
said76
Member
 
Registered: Aug 2011
Posts: 113

Rep: Reputation: Disabled
Internet access problem


Hi,

I was wondering if anyone might be able to help me out. I have just finished building my own desktop and installed Ubuntu Server 14.04 LTS 64bit onto the PC.

After a successful installation, I tried to run the command "aptitude update" but getting lots of "Failed to fetch http://security.ubuntu.com...": could not resolve "security.ubuntu.com". I got a strong feeling that it's not connected properly to the Internet.

I then configured my network interface with dynamic IP by editing /etc/network/interface
# Dynamic IP address
auto eth0
iface eth0 inet dhcp

dns-nameservers 8.8.8.8

saved the file.

Next, run "/etc/init.d/networking restart" but still unable to access to the Internet.
Restarted the PC and this did not work either.

I checked on the back of the machine where the Ethernet network interface is. I saw a solid orange color and a blinking yellow color.

I have even changed the ethernet cable just to make sure it's not the cable. This did not help at all.

My other laptop that's connected to the same modem router as my Ubuntu Server Desktop, is connected to the Internet with no problem. So I know modem router is not the problem.

I got a feeling it might be the machine that I built was not right. But I don't know what else to get around this.

The motherboard I used is Gigabyte H87-D3H.

Thank you very much in advance.
 
Old 12-11-2014, 08:05 AM   #2
rtmistler
Moderator
 
Registered: Mar 2011
Location: USA
Distribution: MINT Debian, Angstrom, SUSE, Ubuntu, Debian
Posts: 9,885
Blog Entries: 13

Rep: Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931
How about the output of "ifconfig -a", and further the output of ethtool with the correct interface, my assumption is that would be eth0, therefore "ethtool eth0".

The output of these commands will show the status of your Ethernet port, whether or not the system believes it to be connected and what speed it believes it to be operating at.

That MB supports 10/100/1000 MB Ethernet speeds so it should work. Solid LED with occasional flashing sounds OK, sounds like link is up physically and there's some data transfer attempting to occur.
 
Old 12-11-2014, 10:54 PM   #3
said76
Member
 
Registered: Aug 2011
Posts: 113

Original Poster
Rep: Reputation: Disabled
Thank you for replying.

When I did "ifconfig -a", I received this:
em1 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 frame:0
collisions:0 txqueuelen:1000
<snip>

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:16 errors:0 dropped:0 overruns:0 frame:0
TX packets:16 <snip>

There is no eth0 at all.

I wonder if I have missed out on something while building up the PC. The network card is embedded on the motherboard so there should be no need to tweak anything to make it to work. Unless, the driver is not found for the ethernet.

Thank you in advance
 
Old 12-12-2014, 06:06 AM   #4
rtmistler
Moderator
 
Registered: Mar 2011
Location: USA
Distribution: MINT Debian, Angstrom, SUSE, Ubuntu, Debian
Posts: 9,885
Blog Entries: 13

Rep: Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931
Use ethtool on em1, that is what the newest Ubuntu is naming their network interfaces.
 
Old 12-13-2014, 01:47 AM   #5
said76
Member
 
Registered: Aug 2011
Posts: 113

Original Poster
Rep: Reputation: Disabled
Thanks again for your reply.

When I did "ethtool em1", I got the following:
Settings for em1:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes: 1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 2
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown (auto)
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: no

Then, I read people who had the similar problem solved it by turning off the auto negotiation.

I ran "ethtool -s em1 autoneg off speed 1000 duplex full"

After this, I unplugged the ethernet cable from the machine and plugged it back in again.

I ran "ethtool em1", I still got the same output
Settings for em1:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes: 1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 2
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown (auto)
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: no

Thank you for your help
 
Old 12-15-2014, 07:32 AM   #6
rtmistler
Moderator
 
Registered: Mar 2011
Location: USA
Distribution: MINT Debian, Angstrom, SUSE, Ubuntu, Debian
Posts: 9,885
Blog Entries: 13

Rep: Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931Reputation: 4931
The most important part of that is that it shows "Link detected: no"

I realize that you've changed the cable and observed the LEDs on that connector; however it appears that the Ethernet still is not connected for some reason.
 
Old 12-16-2014, 11:55 AM   #7
lsalab
LQ Newbie
 
Registered: Jan 2009
Posts: 24

Rep: Reputation: 3
A friend of mine once had a similar problem with ubuntu 14.04 just when it was released. It happened with a hp laptop.

You should take a look at the network-manager, it was screwing my friend's network config and disabling his network interface.

He disabled that service and was up and running in no time. Maybe there's an Ubuntu bug in this package?
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
[SOLVED] PPPOE server access the internet clients fail to access the internet simbini Linux - Newbie 3 08-31-2010 12:37 AM
Trying again. First problem: internet access shame *BSD 12 03-13-2007 06:10 PM
internet access problem using squid soumalya Linux - Networking 6 11-30-2006 07:33 AM
internet access problem superraylo Linux - Networking 4 06-04-2006 10:41 PM
Internet and LAN access is unstable-is this a hardware problem or a software problem? soren625 Linux - Networking 1 06-07-2004 06:43 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 11:23 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration