default route?

sword1

what is the difference b/w these command


ip route 0.0.0.0 0.0.0.0 192.168.12.1
and
ip route default-gateway 192.168.12.1


and is ther any command

ip default- network 192.168.12.1

and do also send me the link of documentation of IOS of router and quick reference command of router ios

networker050184

ip route 0.0.0.0 0.0.0.0 192.168.12.1 is a default route. It is your gateway of last resort. If your router doesn't find a match in the table it will send the packet out the default route.

There is no ip route default-gateway 192.168.12.1 command. There is the ip default-gateway which you are not going to use 99% of the time. It is used if you are not routing ip packets, and you will be routing ip.

The ip default-network command uses that network as a last resort if the router has a route to that network.

You can find prety much all the info on Cisco technology that you need here.

freetech

The first command is good, the rest don't make sense.

Here is a good IOS command reference:
http://www.amazon.com/CCNA-Portable-Command-Guide-Self-Study/dp/1587201933/ref=sr_1_2?ie=UTF8&s=books&qid=1199364772&sr=8-2

networker050184

freetech wrote:

The first command is good, the rest don't make sense.

Here is a good IOS command reference:
http://www.amazon.com/CCNA-Portable-Command-Guide-Self-Study/dp/1587201933/ref=sr_1_2?ie=UTF8&s=books&qid=1199364772&sr=8-2

Don't make sense???

Darthn3ss

freetech wrote:

The first command is good, the rest don't make sense.

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094374.shtml

fault routes are used to direct packets addressed to networks not explicitly listed in the routing table. Default routes are invaluable in topologies where learning all the more specific networks is not desirable, as in case of stub networks, or not feasible due to limited system resources such as memory and processing power.

This document explains how to configure a default route, or gateway of last resort. These IP commands are used:

*

ip default-gateway
*

ip default-network
*

and ip route 0.0.0.0 0.0.0.0

Prerequisites
Requirements

There are no specific requirements for this document.
Components Used

This document is not restricted to specific software and hardware versions. The command outputs shown are from the Cisco 2500 Series routers running Cisco IOS® Software Release 12.2(24a).

The information presented in this document was created from devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If you are working in a live network, ensure that you understand the potential impact of any command before using it.
Conventions

For more information on document conventions, see the Cisco Technical Tips Conventions.
ip default-gateway

The ip default-gateway command differs from the other two commands. It should only be used when ip routing is disabled on the Cisco router.

For instance, if the router is a host in the IP world, you can use this command to define a default gateway for it. You might also use this command when your low end Cisco router is in boot mode in order to TFTP a Cisco IOS® Software image to the router. In boot mode, the router does not have ip routing enabled.

This example defines the router on IP address 172.16.15.4 as the default route:

ip default-gateway 172.16.15.4

ip default-network

Unlike the ip default-gateway command, you can use ip default-network when ip routing is enabled on the Cisco router. When you configure ip default-network the router considers routes to that network for installation as the gateway of last resort on the router.

doesn't make sense???


edit: just reread the OP.. didn't see "ip route" originally... whoops. probably was a typo on his part?

APA

ip default-network x.x.x.x use to work exactly the same as a default route, I rememb er reading that somewhere....

But in an IOS revision they changed it and made it only work if you had the common default route of 0.0.0.0 0.0.0.0 x.x.x.x with the x.x.x.x pointing to an interface on the default network defined by the ip default-network command.....

Seems kind of pointless...... If you have already got a default route pointing to a valid interface why would you need an additional command telling it the same thing....... meh.....

EdTheLad

A.P.A wrote:

Seems kind of pointless...... If you have already got a default route pointing to a valid interface why would you need an additional command telling it the same thing....... meh.....

You need to do some reading on redistributing the default route and classful/classless routing with regard to rip,igrp and eigrp.