date in perl -- one day before

my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime(time() - 24*60*60);                                                                     
my $yesterday_date = sprintf  "%.d-%.2d-%.2d", $year+1900, $mon+1, $mday;                                                                                    
                                                                                                                                                             
my ($sec1,$min1,$hour1,$mday1,$mon1,$year1,$wday1,$yday1,$isdst1) = localtime(time());                                                                       
my $todays_date = sprintf  "%.d-%.2d-%.2d", $year1+1900, $mon1+1, $mday1;            

linux web server info

http://www.the-art-of-web.com/system/

http://www.ducea.com/2006/06/06/rotating-linux-log-files-part-1-syslog/

How to diagnose a linux server if running slow

http://www.ibm.com/developerworks/aix/library/au-satslowsys.html

very good site for postfix

http://vnlinuxworld.blogspot.in/2010/06/postfix-howtos.html

Linux info

varnish -- http://www.mormanski.net/2010/08/14/install-configure-varnish-on-ubuntu-lucid-linux
            -- http://www.lullabot.com/articles/varnish-multiple-web-servers-drupal     
varnish sticky session

LAMP -- http://txt.binnyva.com/2007/04/compile-and-install-lamp-server-from-source-php5-apache2-mysql5/
          -- http://www.devshed.com/c/a/Apache/Building-Apache-the-Way-You-Want-It/12/

linux boot process -- http://www.thegeekstuff.com/2011/02/linux-boot-process/

http://stackoverflow.com/questions/1750194/smtp-why-does-email-needs-envelope-and-what-does-the-envelope-mean

http://unixinterviewquestions.blogspot.in/2012/07/domainkeys-identified-mail-dkim.html

how to use jquery to add new row to table and assgin an incrementing id

http://stackoverflow.com/questions/2307129/how-to-use-jquery-to-add-a-new-row-to-a-table-and-assgin-an-incrementing-id-to

submit a form without page refresh using jquery

http://net.tutsplus.com/tutorials/javascript-ajax/submit-a-form-without-page-refresh-using-jquery/