cron failure message

[Tapas Mishra]

On Tue, Oct 12, 2010 at 1:56 PM, Alex Muntada <alexm at alexm.org> wrote:
> + Tapas Mishra <mightydreams at gmail.com>:
>
>> I am getting above message in cron.
>> It is daily failing.
>
> It seems that your Ubuntu mirror is failing. Choose another one
> from System > Administration > Software Sources.
>
I do not have a GUI on the server.
Can you help to understand which one is failing.
I will modify sources.lst