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Subject: Re: Switching default gateways
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On 12/7/11 9:20 AM, Ross wrote:
> I have a host with two uplinks. One is the default gateway. I want the
> system to automatically switch to the other one if it detects problems
> with the first one. How do I do this?


Hello to you too,


First of all, please realize this isn't a google search field, you're
talking to actual humans and you might want to start off with a proper
greeting.


With regards to your question, this can be done in 2 different ways:


1/ script

Ping your primary gateway, if it stops responding your script changes
the gateway to your backup.

When the primary comes back up, swap again.

Easily done.




2/ routing protocols

Get your 2 upstream routers to announce themselves via a routing
protocol, only works if you have control of said gateways.