IP stands for "Internet Protocol". It is one of the fundamental protocols that powers the internet. IP is how data is able to be routed to the correct destination - your computer is assigned an IP address, and when you need to get data back, that data gets sent to your IP address.

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How do I route a spare network interface through an SSH tunnel?

I just bought a Raspberry Pi and I am wanting to route an ad hoc wireless network interface fully through an SSH tunnel that was created using another wireless interface. I want to do this so that I ...
0
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1answer
66 views

Masquerade not working sometimes [on hold]

This is a cross post from severfault, where I got no answer. I have an issue with private network traffic not being masqueraded in very specific circumstances. The network is a group of VMware ...
7
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2answers
33 views

SSH session through OpenVPN cuts off / locks up after a few lines

I have a large number of identical fanless PCs running debian 6 (ARM). Most of these are connected via comcast and work ok. There are some that are connected to 'WiMax' modems and are having ...
2
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1answer
3k views

Using ip addr instead of ifconfig reports “RTNETLINK answers: File exists” on Debian

I have a Debian system working as a wireless router with eth0 and wlan0. Now I added an additional network manually on eth1 with ifconfig: alix:~# ifconfig eth1 192.168.0.2 netmask 255.255.255.0 ...
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2answers
407 views

Fedora 18 host cannot ping Windows XP guest

I have my laptop running Fedora 18. I want to run a Windows XP guest using VirtualBox 4.2.6. My configuration seems correct, here is my networking report. Fedora 18 host lo: ...
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2answers
63 views

How to determine eth0 gateway address when it is not the default gateway?

In my system I have eth0 (which may or may not be connected) and a modem on ppp0 (which always may be up or down). The the case where both interfaces are up and ppp0 is the default route, I'd like to ...
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3answers
49 views

Enabling IP forwarding at kernel compile time

I am compiling a kernel for a router. I know a way to enable IP forwarding in an existing Linux system. At compile time, CONFIG_IP_FORWARD is said to do the same task. I am configuring version ...
3
votes
2answers
457 views

policy routing problem with load balanced ppp connections

This my setup using Debian 6.0.6. It's role is a proxy server and a load balancer using eight 3G modems. First and foremost: Whenever a ppp connection dials it takes over the default gateway which ...
2
votes
2answers
291 views

keep losing IP with dhcpcd

I have an Arch Linux install in a VirtualBox VM, and as I'm working all of a sudden, it will lose it's dynamic IP address. When this happens, if I check on the status of the dhcpcd service it says ...
0
votes
1answer
54 views

How to request a specific IP address from DHCP server?

I'm running Angstrom Linux on an embedded device (BeagleBoard-xM). I managed wireless connection via a Wi-Fi adapter. When I load its driver using modprobe, BB-xM requests an IP address from router ...
0
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4answers
40 views

Linux routing tables

I'm trying to learn Linux routing tables and ran into bit of snag. In the example below I'm not sure what is happening. My understanding is 0.0.0.0 means that for line 1 and 2 any packets outside of ...
2
votes
1answer
42 views

How do I create an IPv6 overlay network?

I would like to create host-only IPv6 networks on two hosts and then route between them. On each host, there will be a dummy interface, at ipv6_prefix::9. I would like to be able to ping that ...
4
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1answer
60 views

Why is this static route not taking effect?

Original Question I am running Ubuntu and network manager. I have two different interfaces, eth0 and eth1. Network manager has (as far as I can tell) correctly added this manual route: ~$ ip route ...
5
votes
4answers
219 views

History of IP addresses that accesed a server via ssh

It has come to my attention that a server of mine has been hacked and infected with a known chinese botnet. It was a prototype/testing virtual machine with its own static IP(US address) so no harm ...
2
votes
1answer
280 views

Static routes in route-eth0 ignored

Why might route-eth0 be ignored but route-eth1 not? Might be because eth0 is using DHCP and eth1 is statically-configured? I have some static routes configured in ...
6
votes
3answers
70 views

How does one capture traffic on virtual interfaces?

I would like to capture traffic on Linux virtual interfaces, for debugging purposes. I have been experimenting with veth, tun and dummy interface types; on all three, I am having trouble getting ...
1
vote
1answer
11 views

tcp/ip - trigger action or event after period of no network activity on certain port(s)

Is it possible, perhaps using iptables or one of the wrappers/frontends to iptables, to trigger an action or run a script after a certain period of time has elapsed with no network activity on a ...
4
votes
1answer
35 views

Send traffic to self over physical network on Ubuntu

I have a dual port ethernet NIC and let's say I have connected both ports in a loop and assigned the following IPs to the 2 ethernet interfaces: eth2 -> 192.168.2.1 eth3 -> 192.168.3.1 I want to ...
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0answers
27 views

Get user login name and address on bad login attempt [Dovecot]

Background I am trying to develop a method to ban users who exhibit strange behavior when logging into Dovecot by obtaining their POP-ID/login name and IP address. I want to send that information to a ...
1
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2answers
44 views

Can't access ssh in my VM Centos

My Cento's IP is diferent of the normal. And I cant access it in a ssh command And when I tried access using ssh noting I want to use ssh and samba client, but my IP is diferent. And I have ...
0
votes
0answers
24 views

Possibility to use app in LAN and via Internet

I use web based (https encapsulated) app in my home network and via Internet. The app has dedicated Linux desktop client (I use Mageia ver4 Linux for laptop). Of course server address I have connected ...
0
votes
1answer
27 views

installation causing error

I have downloaded g2ipmsg from http://www.ipmsg.org/archive/g2ipmsg-0.9.6.tar.gz while installation this package it causing some error checking for G2IPMSG... configure: error: Package ...
1
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2answers
32 views

What could cause a ping request to return inconsistently timed results

Here is a sample run: 64 bytes from 192.168.1.9: icmp_seq=27 ttl=64 time=8852.917 ms 64 bytes from 192.168.1.9: icmp_seq=28 ttl=64 time=7918.074 ms 64 bytes from 192.168.1.9: icmp_seq=29 ttl=64 ...
28
votes
2answers
2k views

How is it that missing 0s are automatically added in IP addresses? (`ping 10.5` equivalent to `ping 10.0.0.5`)

I accidentally typed ssh 10.0.05 instead of ssh 10.0.0.5 and was very surprised that it worked. I also tried 10.005 and 10.5 and those also expanded automagically to 10.0.0.5. I also tried ...
0
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0answers
37 views

SUSE Linux 12 - configuring IP alias

I want to setup an IP address alias on a network card. I created a file /etc/sysconfig/network/ifcfg-ens160 and its contents are: BOOTPROTO='static' STARTMODE='onboot' IPADDR='192.168.0.113' ...
2
votes
1answer
31 views

tcpdump command works only on local ip

I am trying to capture some IP packets in my personal LAN with tcpdump, through the command tcpdump -A -i eth0 'tcp and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0) ...
2
votes
1answer
1k views

Virtualbox NAT + Host-Only Adapter

My host is Ubuntu 12.04 and guest is a Debian squeeze (LAMP server). I want to allow the host to connect the guest. and allow the guest to connect the internet. The guest should not be enabled from ...
2
votes
2answers
117 views

SSH access from inside and outside a LAN using the same terminal command

I have a Raspberry Pi (RPi) and I am making remote connections to it using ssh. I have managed to set up ssh correctly such that I can access the RPi both from a local area network and from the ...
3
votes
1answer
58 views

Using shell script to select static IPv4 configuration according to router address

I have Linux Mint 15, I live in a university where the hostel and lab have separate static IP settings. Is there a way to set up the connection mechanism so that my laptop will automatically select ...
3
votes
3answers
3k views

Make some virtual MAC address

I want to make some virtual MAC addresses for my network adapter or wireless adapter, so I can connect to network with more than one IP address from one computer or laptop. How can I do it? (I know ...
0
votes
0answers
88 views

On ssh connection the auth.log shows as source IP the external IP of the server instead of the IP of the client

I have a very odd situation with my ssh connection. Every time I connect to my server, whatever is my external ip, the connection have as source the server's external ip. Example Server S.O.: ...
2
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5answers
3k views

How to get netmask from bash?

I want to get my netmask on Linux. It is outputted with ifconfig but I want to extract the string.
3
votes
1answer
539 views

Route SSH to host through interface

Is it possible to route all outgoing requests for SSH (port 22) to mydynamicdns.afraid.org via wlan0 instead of eth0 when both are connected? Since my IP is dynamic, I would like to use a name ...
1
vote
3answers
277 views

Why can't I ping Google?

I can't ping google.com (unknown host). But I can ping IP addresses. I tried to ping the IP address of Google but it doesn't work. resolv.conf nameserver 8.8.8.8 nameserver 209.139.209.33 ...
0
votes
1answer
44 views

IP Prefix - how do I declare this?

Hi I have an IP Prefix issue I would like to declare the following IP's as "safe" using ip prefix "methodology" ("?") The IP's first three parts of the IP have been doctored to protect the innocent, ...
1
vote
0answers
43 views

Linux Source Routing with one gateway

I've a Linux box which have IP 10.1.1.100/24 on eth0 with gateway 10.1.1.1 and as well as 20.1.1.1 on eth0:1 and 20.1.1.2 on eth0:2 . Is there any way that I could communicate to a remote machine ...
9
votes
1answer
224 views

Is it better to set -j REJECT or -j DROP in iptables?

There's an example of iptables rules on archlinux wiki: # Generated by iptables-save v1.4.18 on Sun Mar 17 14:21:12 2013 *filter :INPUT DROP [0:0] :FORWARD DROP [0:0] :OUTPUT ACCEPT [0:0] :TCP - ...
35
votes
11answers
21k views

How can I get my external IP address in bash?

I need to find my external IP address from a bash script. At the moment I use this function: myip () { lwp-request -o text checkip.dyndns.org | awk '{ print $NF }' } But it depends on ...
0
votes
2answers
236 views

Hostname and IP address mapping in /etc/hosts

In my linux machine, when I run hostname, it shows mongodb, but when I run host mongodb, it shows: mongodb@mongodb:/var/hadoop/hadoop-1.2.1/bin$ host mongodb Host mongodb not found: 2(SERVFAIL) My ...
1
vote
1answer
67 views

how to check if the kernel support for ip alias?

it surprisingly that I get no explicit results when I googled "kernel ip alias support", and I have looked up the linux network administrator, 3rd edition, it says: check that you have a ...
0
votes
1answer
45 views

host only ip address: can it be 10.*.*.*?

My router is set to have computers IP range from 10.1.1.1 to 10.1.1.60 I'm trying to run Linux in virtual box in a host computer with windows 7. The host computer has 10.1.1.5 currently, which is ...
0
votes
1answer
27 views

ssh login after changed IP

I have server running Ubuntu 12.04.2 LTS (GNU/Linux 2.6.32-042stab078.28 i686) Had no problem logging in to the server via ssh until my Internet Provider changed my IP. Now, the server keeps adding ...
8
votes
1answer
168 views

Send a packet over the network even when its target is the local host

Under Linux if you send a packet to the address of one of its network interfaces, this packet is routed internally, it is never sent over the network. That's the right thing in 99.99% of the cases. ...
1
vote
0answers
74 views

Debian access point is detected, but provides no Internet access

I am use Debian sid. I want to share my network (ppp0) via AP (Access Point) to my mobile device. This is my configuration. /etc/hostapd/hostapd.conf : # WiFi Hotspot interface=wlan0 driver=nl80211 ...
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2answers
186 views

Finding the PID of the process using a specific port?

I am installing hadoop on my Ubuntu system. When I start it, it reports that port 9000 is busy. I used netstat -nlp|grep 9000 to see if such a port exists and I got this: tcp 0 0 ...
0
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2answers
126 views

I want a static IP address for my (network? or computer?)

Me and two friends have been making a video game. We've thought about download hosting a bit, but found that Mediafire, Box, and those sorts of file-hosting sites' maximum free file-upload size is far ...
0
votes
2answers
123 views

Connecting to localhost via system IP address

I am using Linux Mint 15, and I am running a Ruby web server(Thin) on port 3000. I can connect from my machine via localhost:3000, but the moment I type in the system IP address (eg. ...
7
votes
1answer
1k views

Change remote host IP address without losing control (Linux)

How can I change a remote host primary IP address without getting disconnected at all (without being in a "no IP addr" state). The matter is poorly discussed on Internet (according to my research). ...
0
votes
1answer
496 views

Is there any IP messenger for Linux (CentOS)?

Currently am using a Linux (CentOS) machine. Is there any IP messenger for CentOS like iptux and Gnome IP Messenger?
2
votes
1answer
315 views

Static IP config no longer persistent in CentOS6

I was messing around with KVM in CentOS 6.3 when I noticed I was having problems with the IP address of my principle network connection (eth0). I backed out my bridge and restored the network-script ...