Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [routing]

Routing (in IP-based networks) is the process of selecting paths in a network along which to send network traffic.

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How to find out which interface am I using for connecting to the internet?

I have eth0 and wlan0 according to ifconfig and I can ping google.com. How can I find out (with a normal user, not root) what interface is active, as in, what interface did the ping (or whatever, ping is not mandatory) use? I am using Ubuntu 11.04…
LanceBaynes
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What is kernel ip forwarding?

I have seen on many blogs, using this command to enable IP forwarding while using many network security/sniffing tools on linux echo 1 > /proc/sys/net/ipv4/ip_forward Can anyone explain me in layman terms, what essentially does this command do?…
Madhur Ahuja
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What is the meaning of 0.0.0.0 as a gateway?

Can anyone clarify gateway assignment for me? What is the difference between adding a gateway as 0.0.0.0 and assigning a specific IP address as a gateway?
user2720323
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Reply on same interface as incoming?

I have a system with two interfaces. Both interfaces are connected to the internet. One of them is set as the default route; a side effect of this is that if a packet comes in on the non-default-route interface, the reply is sent back through the…
Shawn J. Goff
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Bind unix program to specific network interface

Question: How do I launch a program while ensuring that its network access is bound via a specific network interface? Case: I want to access two distinct machines with the same IP (192.168.1.1), but accessible via two different network interfaces…
Skeen
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Use ssh with a specific network interface

I'm using openconnect to connect to vpn. After entering my credentials, I get this: POST https://domain.name/... Got CONNECT response: HTTP/1.1 200 OK CSTP connected. DPD 30, Keepalive 30 Connected tun0 as xxx.xxx.xxx.xxx, using SSL Established DTLS…
axel22
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How to refuse routes that are PUSHed by OpenVPN server?

When I establish an OpenVPN client connection over the Internet to our corporate OpenVPN server, it pushes several static routes. Unfortunately, these routes break some connectivity within my local network environment, as they collide with my own…
mbaitoff
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Tools for Debugging Routing Tables on a Linux Machine?

Is there a tool that debugs routing tables on a Linux machine? I mean one that I can use by inputting an ip address into it, it'll take the existing routing table into account and output the matches from the table, so I can get an idea where the…
leeand00
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Output traffic on different interfaces based on destination port

My question is basically the same as Only allow certain outbound traffic on certain interfaces. I have two interfaces eth1 (10.0.0.2) and wlan0 (192.168.0.2). My default route is for eth1. Let's say I want all https-traffic to go through wlan0. Now…
rumpel
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OpenVPN: Push a route to client with a different gateway

I would like my OpenVPN server to push a route down to the client with a different default gateway. Specifically, my OpenVPN server has an internal IP address of 10.0.0.1, and I would like it to push a route of 10.10.10.1/24 using gateway…
Lorin Hochstein
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How can I change the default gateway?

Currently I'm running a FreeBSD 9.1 and the default gateway is already configured in the rc.conf. rc.conf: defaultrouter = "10.0.0.1" But now I want to change the default gateway without rebooting the system, is this possible?
WWW
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How can I use Linux as a Gateway?

NOTE: If client devices (computer B in this example) want to obtain internet through the gateway computer, maybe they still need to configure nameserver resolution. This is not explained here (a gateway does not necessarily serve internet). I…
Sopalajo de Arrierez
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OpenConnect: Setting default routes

I'm trying to use OpenConnect to connect to my company's Cisco VPN (AnyConnect) The connection seems to work just fine, what I'm not understanding is how to set up routing. I'm doing this from the command line. I use the default VPN script to…
Aditya K
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What is the interface scope (global vs. link) used for?

Routing table entries have an attribute scope. I would like to know how the change from global to link (or the other way round) affects the network system.
Hauke Laging
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Modifying existing route entry in linux

what is the command to modify metric of an existing route entry in linux? I am able to change gateway of an existing entry using "ip route change" command as below but not able to change metrics. Is there any other command for that? route…
user1762571
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