CentOS - Dec 2009 - questions relate to "sar"

We have CENTOS 5.3 on DELL server.  I tried to use "sar -b" or
"sar -u" and it only show report starting on 12:00 A.M.

my questions are:

1. for "sar -u" or "sar -b" how can I generate two or three
days ago report?

2. how to generate daily report from "sa2 " peocess?

Thanks.

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mcclnx mcc wrote:
> We have CENTOS 5.3 on DELL server.  I tried to use "sar -b" or
"sar -u" and it only show report starting on 12:00 A.M.
>
> my questions are:
>
> 1. for "sar -u" or "sar -b" how can I generate two or
three days ago report?
>
> 2. how to generate daily report from "sa2 " peocess?
>   
I suggest reading the man pages on sar, and associated functions.

sar -f /var/log/sa/sa22 would process the data for the 22nd, see what
files you have available in /var/log/sa/ ... my system seems to be
keeping 18 days worth.

sa2 is used to create the daily reporrt files described above. If you
want to create a daily report in a specific format, you'll probably want
to write your own script that you invoke from crontab