First you need to figure out the reason of your system failure. If its complete power failure, then kexec wont be able to load a new kernel in current context.
Secondly, is kexec properly configured in your system?

Chandan Kumar
Tata Consultancy Services
Mailto: chandan12.k@tcs.com
Website:
http://www.tcs.com
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From: Gallus <gall.cwpl@gmail.com>
To: "Discussion list for crash utility usage,        maintenance and development" <crash-utility@redhat.com>
Date: 02/09/2010 07:10 PM
Subject: [Crash-utility] Reasons why kdump isn't activated
Sent by: crash-utility-bounces@redhat.com





Hi,
what can be any reasons why kdump mechanism isn't triggered? My first
though is that it means a hardware failure, not a kernel problem.

Regards,
Mariusz Gniazdowski

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