ifconfig (short for interface configuration) is a system administration utility

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2answers
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eth0 NO-CARRIER, ifconfig shows no IP address

I left Ubuntu and came back after a while so I don't remember much. Now I'm trying to get my IP address. All I'm getting from running ifconfig is eth0 Link encap:Ethernet HWaddr 3c:97:0e:11:22:...
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3answers
5k views

How can I display eth0's IP address at the login screen on Precise Server?

The server I administrate, inconveniently enough, has a dynamic IP address assigned by DHCP. The convenient counterbalance, though, is that it happens to be set up about two feet from where I sit. I ...
0
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1answer
30 views

How to enable ethernet connection on Lubuntu?

I installed Lubuntu OS on my Odroid-XU4. I connected an ethernet cable and also a Realtex Wifi adapter to it. But when I run ifconfig -a, none of the adapters are shown. How can I fix this problem?
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0answers
12 views

How does MAC Address cloning works in Ubuntu from “Edit Connections”?

I found that cloning MAC Address works very well from "Edit connections" method than changing mac address with "ifconfig" command. sudo ifconfig wlan0 down sudo ifconfig wlan0 hw ether sudo ifconfig ...
2
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0answers
76 views

Apply static IP address change in /etc/network/interfaces in Ubuntu 16.04

TL;DR: In Ubuntu 14.04, If you change a static IP address in /etc/network/interfaces and apply the changes with ifdown and then ifup command everything works fine. But this sequence is not working in ...
4
votes
6answers
37k views

Is there a safe way to disable DHCP from command line?

Short version I know this question is very similar to others and I did really search the Internet for answers, but it seems that no approach is working or the solutions seem to be "to complicated to ...
1
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2answers
7k views

How do I make the script to run automatically when tun0 interface up/down events?

I use VPN client to connect to my corporate servers. It creates tun0 interface after starting the client. I've written script which install specific routes point to tun0 interface and rest to use ...
0
votes
1answer
32 views

Configured a static ip but it didn't take effect immediately

So I configured a static ip connection on the GUI but it didn't seems to take effect when I check with ifconfig. I think if I restart the computer, it'll take effect but it sounds "overkill" for an ip ...
0
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1answer
37 views

no eth0 and no wired internet connection

yesterday all was fine and Dandy until the internet service went out due to a storm. After my isp got their stuff together all my other devices had internet except for my ubuntu desktop. I booted it ...
0
votes
1answer
27 views

Redirect Command to Email

I have a PXE server and need to do a redirect command at the end of the script. ifconfig | grep inet >> ip.txt send to My_EMAIL Am I on the right path? Edit include from answer posted as an ...
0
votes
1answer
32 views

ifconfig fixed ip address is lost after a while

I'm using ubuntu LTS14.04 and I want to make some lab experiments with two computers and a switch. Both computers are configured to start with DHCP but I want to assign two fixed ip addresses to each ...
2
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0answers
90 views

Network Interface does not come up automatically

I have a couple of Jetson TK1s and Jetson TX1s running Ubuntu 14.04 (Linux4Tegra). I need to be able to switch between two network configurations - an "office" one where I'm in the office and can ...
0
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2answers
20 views

When using ifconfig to see my Mac address, which one is for connecting to a wireless network?

I am using an older laptop that I converted from windows xp to ubuntu 14.04, so my question is about what Hardware address should I use to connect to my college network? The reason I ask is because ...
0
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0answers
172 views

Ifup/ifdown problems in Ubuntu 14.04

I am condiguring my eth0 NIC connection through /etc/network/interfaces file. But each time I changed this file, I ran ifdown eth0 and it responded with waiting for lock on ifstate file and stuck here....
2
votes
3answers
6k views

ethernet disconnected, shows up in ifconfig

I am running 11.04, no remix. After installation, I could use wireless networks, but not ethernet. When I click on the connections menu item, it says Wired Network disconnected How do I fix this? ...
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0answers
5k views

How to change wlan0's channel

When setting the channel to wlan0, I get an error: SET failed on device wlan0 ; Device or resource busy. I tried to shutdown wlan0 by: sudo ifconfig wlan0 down and wlan0 did not appear in the ...
1
vote
1answer
70 views

Ifconfig does not show my IP [closed]

When i'm putting the code on: ifconfig ifconfig results in a terminal shows: eth0 Link encap:Ethernet HWaddr: f8:a9:63:64:3f:1c UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets: 0 errors:0 ...
0
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1answer
52 views

How to configure two interfaces for internet and lan?

i have server which two int. and static ip. And i need one work in local network and another work to internet. How configure interfaces ?
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2answers
919 views

How can I bring down this tun interface?

I can neither bring down nor delete this tun interface which is added on startup. Here's the output when I run ifconfig: eth0 Link encap:Ethernet HWaddr 50:b7:c3:92:38:e2 UP ...
0
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0answers
38 views

em1 needs to be manually started on boot

On every boot, I have to run the following commands to get my ethernet to function: sudo ifconfig em1 up sudo dhclient em1 sudo /etc/init.d/networking restart The ethernet adapter was working fine ...
1
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4answers
14k views

The command could not be located because '/sbin' is not included in the PATH environment variable

I have a severe problem today: when I type ifconfig it does not show ip configuration on ubuntu 12.04. Can anyone help me on this? Here is the result of ifconfig: Command 'ifconfig' is available in '...
1
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1answer
57 views

Odd interface when running sudo ifconfig

So, I've noticed an odd looking interface... Apparently, it has it's own MAC address (which I don't even know where it came from... Attempting to perform an OUI lookup on it returns no results...) ...
0
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1answer
71 views

Connected but no internet access in Ubuntu 14.04

I have been using this broadband connection for a long time. Suddenly it stopped working, it shows "Connected DSL connection 1". But whenever I try to browse any website, it doesn't load and shows "...
1
vote
1answer
195 views

Two computer MAC Addresses

In Ubuntu 14.04, when I run the command ifconfig | grep HWaddr to know the mac address of my computer, I find two MAC addresses, how is it possible? zina@zina-HP-Pavilion-g4-Notebook-PC:~$ ifconfig | ...
18
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6answers
43k views

What is the active MAC Address of my computer?

While looking to find the MAC Address of my computer as it appears to a wireless network, it was recommended that I run ifconfig. Having executed that command in the Terminal, I noticed that, unlike ...
0
votes
1answer
241 views

ifup eth0: unknown host

unfortunately, i am in Ubuntu Recovery Mode. I need Internet connection but, i fail to bring it up. $ ifconfig enp0s2 Link encap:Ethernet HWaddr xxxx inet addr: inet6 addr: ......
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votes
2answers
11k views

Identify Wireless MAC Address

I have a desktop for which I am using an Asus N-10 USB Wireless Adapter. No driver software is needed I guess since I can see the available wifi networks. However, I am unable to connect as the "MAC ...
0
votes
1answer
1k views

VirtualBox Ubuntu 14.04 - Bridge adapter not working

I'm having some troubles setting up my network connection using the Bridged Adapter configuration. I'm just starting with Linux and even if I was going through different forum discussions on the web, ...
1
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1answer
371 views

ifconfig sets wrong broadcast until ran again

This issue is very confusing for me. ifconfig sets a different broadcast address than specified, until I run the same command again. I'm trying to change the eth0 interface: inet addr:172.23.5.1 ...
0
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0answers
37 views

No internet connection after reboot

I have an error on my debian server, hope you can help me anyway, because the systems aren't that different. I rebooted my vServer (Debian 8) and it doesn't came back up. Well, I used the rescue ...
0
votes
1answer
52 views

How to add multiple ips to ubuntu 12.04 server?

i hope that some can help me here. I have bought 6 additional IP:S and i need to run two gaming servers at same time for same game. So i need to add another ip so i can run these two servers at same ...
0
votes
1answer
91 views

Can not configure eth0 and eth1

I have two physical networks: eth0 192.168.0.0/24 with with several PCs and NAT adresss 192.168.0.1 where PPPoE connecting to inet; eth1 192.168.0.1/24 with several PCs and no internet. auto lo ...
4
votes
1answer
11k views

Connecting to internet after clean install of ubuntu server 12.04

I've installed ubuntu server on my computer. I would like to connect to the internet to download more software. I've done: ifconfig eth0 up so when I print ifconfig I can see the eth0 listed, but ...
0
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0answers
25 views

Is that right configuration?

I'm new to ubuntu and networking too i used ip addr to check the ip address and got 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default link/loopback 00:00:00:00:...
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0answers
28 views

How can I use multiple network connections from the same host?

Suppose I could use both a wired and wireless connection; now, let's say I want to run firefox using the wireless and steam using the wired, how can I achieve that? How can I plug them in? First ...
0
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0answers
754 views

Cannot configure eth0 in Ubuntu Server 15.10

My system just went a bit crazy past night. It was fully working, and nobody touched it. I configured a static public IP in my Ubuntu, and I could connect to it everywhere (My system accepts public ...
4
votes
5answers
32k views

ifconfig : Command 'ifconfig' is available in '/sbin/ifconfig'

My question is related to another open question. My echo $PATH gives me an output which is like /home/sahil/.rvm/gems/ruby-1.9.3-p125/bin:/home/sahil/.rvm/gems/ruby-1.9.3-p125@global/bin:/home/...
7
votes
1answer
47k views

Is it possible to use Ifconfig to switch an interface to DHCP and if not, what is the best way?

I have just set up a new Ubuntu server and I am going to be doing a lot of networking tests. During setup, I simply skipped the network step. I now need to switch between DHCP and an address quite ...
0
votes
1answer
4k views

Ubuntu-server first start

How do you change network settings? ifconfig gives ip 192.168.122.1 (I ping it and the Ethernet card works) I use sudo vi /etc/network/interfeces then after editing auto eth0 ifaces eth0 inet ...
4
votes
1answer
205 views

Find MAC address in the filesystem

My laptop is down, but I need to extract its MAC address thas was previously used to establish wifi connection. The filesystem was cloned, so I am trying to find any configurational file which ...
0
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0answers
25 views

upstart my.conf ifconfig changes seem to either have no effect, or get overwritten during startup

I have installed an upstart script like this: # This needs to go into the /etc/init/ folder description "Run MCP" start on runlevel [2345] stop on runlevel [016] console output script # ...
3
votes
2answers
8k views

What does interrupt in eth0 mean?

I wonder if "Interrupt" affects internet connection. eth0 Link encap:Ethernet HWaddr 60:eb:69:6c:55:83 UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 ...
1
vote
1answer
797 views

scripts in if-up.d not executed when ppp connection is created

I have a simple script "test" in /etc/network/if-up.d directory. The script contains below commands. It creates a empty text file, whenever an interfaces changes state from down to up. #!/bin/bash ...
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vote
0answers
194 views

ipv6 global address missing after link flap

in linux/ubuntu after the link flap on an interface the global ipv6 address is flushed out & not seen in ifconfig. Any kernel patch/sysctl to retain the ipv6 address configured after the link flap....
0
votes
1answer
65 views

usb Ethernet adapter disapear after Stoping network-manager service

I am using D-Link (DUB-E100) for handling 2 seperated network under linux ubuntu 14.04. at first i have 2 eth on my system . ifconfig yields: eth0 Link encap:Ethernet HWaddr b8:ae:ed:70:27:3e ...
3
votes
3answers
9k views

NetworkManager problem with 'cloned MAC address'

My problem is that at univ. each desktop computer is given a 'fake'/'cloned' MAC address which is recognised by our network and let us in without further authentication/VPN and the likes (don't ask ...
0
votes
0answers
64 views

Use systemd to “mount” wlan0 at boot

Context (if needed) : at boot, the service "myservice" is launched. It manages to "up" the wlan0 interface. But it does not exist yet at boot. ifconfig, after boot, lists only eth0 and lo. If I ...
0
votes
1answer
163 views

cannot ping localhost

I am not able to ping localhost ashish@ashishk:~$ ping localhost PING localhost (127.0.0.1) 56(84) bytes of data. ^C --- localhost ping statistics --- 16 packets transmitted, 0 ...
0
votes
0answers
30 views

Networking Issue, Binding on 14.04

IPs routed at the switch just fine. interface Vlan100 ip address xxx.xxx.235.1 255.255.255.0 secondary ip address xxx.xxx.236.1 255.255.255.0 secondary ip address xxx.xxx.237.1 255.255.255.0 ...
0
votes
1answer
69 views

Xubuntu Install-No Network

I installed Xubuntu 14.04 clean on a Dell Vostro 1000 and now I have no network at all. Entering ifconfig gets a return of ifconfig not found. Everything was fine from the live disk.