Q. How do I setup a default gateway on Debian or Ubuntu Linux? My router IP is 192.168.1.254 and I’d like to setup this as a default gateway for Debian Linux.
A. You can use command line tool such as
a] ip command – show / manipulate routing, devices, policy routing and tunnels
b] route command – show / manipulate the IP routing table
c] Save routing information to a configuration file so that after reboot you get same default gateway.
ip command to set a default router to 192.168.1.254
Login as the root and type:
# ip route add default via 192.168.1.254
OR
$ sudo ip route add default via 192.168.1.254
route command to set a default router to 192.168.1.254
Login as the root and type:
# route add default gw 192.168.1.254
OR
$ sudo route add default gw 192.168.1.254
Save routing information to a configuration file /etc/network/interfaces
Open /etc/network/interfaces file
# vi /etc/network/interfaces
OR
$ sudo vi /etc/network/interfaces
Find eth0 or desired network interface and add following option
gateway 192.168.1.254
Save and close the file. Restart networking:
# /etc/init.d/networking restart
OR
$ sudo /etc/init.d/networking restart
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I also want to set my defualt DNS server and proxy settings, just like in windows. How do I do that ??
Rajesh,
In Ubuntu, you can either add the ‘nameserver’ lines in /etc/resolv.conf like “shutty” shows, or use the recommended method in Ubuntu Precise (12.04 LTS) by adding “dns-nameservers ” and “dns-search ” in /etc/network/interfaces, like so:
# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.3.1
netmask 255.255.255.0
# dns-* options are implemented by the resolvconf package, if installed
dns-nameservers 8.8.8.8
dns-search lab.internal
Rajesh,
for dns, edit file /etc/resolv.conf and add lines
nameserver 1.1.1.1
nameserver 2.2.2.2
(where 1.1.1.1 and 2.2.2.2 are your nameservers)
for proxy, use your browser configuration
How do I add a second gateway on higher metric incase the first goes down?
Petrus,
You need to install routed and configure /etc/gateway. Another recommended option is install zebra / Quagga server and configure it. Both allows you to define and configure various routing parameters including metric.
http://www.quagga.net/
How can I get (in a variable) the current default gateway? Is there a sort of “default gateway enviroment variable” that I can read?
Thanks
Run following to display default gateway:
ip route show | grep default | awk '{ print $3}'Use following to store gateway IP in a variable called GW:
GW=$(ip route show | grep default | awk '{ print $3}')echo $GW
vivek, many many many thanks. It works!
For two interfaces that both do dhcp the metrics on the default gateway can be added like this.
auto eth1
iface eth1 inet dhcp
metric 10
auto eth2
iface eth2 inet dhcp
metric 20
Is there any way,so that we can give proxy addresss frm command line apart from browser.because if we give this from command line,it will be applicable to all system.
I have two interfaces, eth0 & eth1. eth0 fixed IP 192.168.1.20 hardwired to test machine with fixed IP 192.168.1.6, (not easily altered).
I want eth1 to connect to internet via a DHCP Server Router. Without eth1 enabled there is no problem but as soon as I enable eth1 as DHCP client I lose any access to 192.168.1.6
Have spent many hours altering the route(s), etc., with no success.
Do I have to use ipchains or can it be achieved with route?
I am having some routing problems with Ubuntu 9.04:
Whenever I start up my system, the Internet won’t work unless I do:
"sudo route add default gw 192.168.1.254"I tried to alter /etc/network/interfaces, but with no luck. After restart, it doesn’t work. executing route prints:
catalin@lolinux:~$ route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 * 255.255.255.0 U 0 0 0 wlan0
After I manually add the gateway, everything is fine, and route prints another gateway:
catalin@lolinux:~$ route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 * 255.255.255.0 U 0 0 0 wlan0
default dsldevice.lan 0.0.0.0 UG 0 0 0 wlan0
Is there any difference from what I altered and the kernel routing table? If there is, how do I modify that? Or would a startup script be a better solution?
I have the “gateway 192.168.1.1” in my network file but I’m still required to manually set the route after reboot. This behavior began only after I “bonded” my two NIC’s. The routing table before the manual route command shows
Kernel IP routing tableDestination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 bond0
192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth1
192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 eth0
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth1
0.0.0.0 192.168.1.1 0.0.0.0 UG 100 0 0 bond0
and after adds this one line just below the 169.254… line
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 bond0Am I missing something or am I experiencing a true bug?
I’m using Kubuntu 9.04 Jaunty.
I am having the same problem..I have to manually set my default gateway after each boot up even though all my network settings include it. How do I get it to stick?
I eventually removed Network Manager. Set everything up manually and it works fine.
I just switched to static ip’s and set everything through wicd..works perfectly. Also I used the network admin tool and I believe that screwed up lots of things.
How can I find Gateway server !? to add the numbers to the address code!?
How can i use 2 gateway , I have a complex network using 2 ISP and Linux as a cache and firewall and a router.
i WANT lINUX router to be able to use both ISP in same time and could nat global IP.
I am using my nanostation 5 as a router… but I can’t receive ping from the ISP gateway… even though I have my ip in the same range. I found this site but the GW isn’t adding… Here are my tables
Destination Gateway Genmask Flags Metric Ref Use Iface
10.64.64.64 * 255.255.255.255 UH 0 0 0 ppp0
10.29.136.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default * 0.0.0.0 U 0 0 0 ppp0
My ip range is 10.29.136.0… I need to add 10.29.136.1 as GW
youtr ip 169.254 its not corect. Reset your router
Hehe
funny thing here! very old Debian distro, I’m trying to add new default gateway via.. tun interface (VPN), but it’s refusing to add anything :D
solved, I’ve used 10.10.0.2 as gateway which is IP alias of VPN
add the following to the bottom of your /etc/network/interfaces file
# Static route
up route add -net xxx.xxx.xxx.xxx netmask xxx.xxx.xxx.xxx dev ethX
I use the following commands to add a new gateway and remove an existing one :
sudo route add default gw 192.168.12.1 eth1sudo route delete default gw 10.0.2.2 eth0