Install Kernel 3.0.4

It is always good to say that you have latest kernel running in your machine. I have upgraded kernel from debian experimental and testing repositories . That was simple and straight forward. But you get real happy when you build a kernel from the source.

This was my first experience in upgrading kernel to 3.0.4 from source and even I don't know whether I can successfully complete or not. But I did this and love to share my experience with all you guys!

Before dive in to this just walk-through this document to learn about kernel.

TLDP-Linux Kernel

Download the latest kernel from Linux Kernel Archive 

# wget http://www.kernel.org/pub/linux/kernel/v3.0/linux-3.0.4.tar.bz2

Extract the kernel

#  bzip2 -dc linux-3.X.tar.bz2 | tar xvf -

Move to the directory where kernel source code is extracted

# mv linux-3.0.4/

Configure your kernel

Use make menuconfig or make config for configuring your kernel. I tried make menuconfig this will give you text based menus

# make menuconfig

Make the kernel 

# make bzImage 

Making kernel modules 

# make modules

This will compile all the modules for kernel 3.0.1

Install the modules compiled

# make modules_install

This will copy all kernel modules to /lib/modules/3.0.4.

Install the new kernel 

# make install

This will copy files vmlinuz-3.0.4, initrd.img-3.0.4 and config-3.0.4 to your /boot directory.

Execute below command in your shell, if initrd.img-3.0.4 is not created.

# update-initramfs -u -k 3.0.4

Configure your Grub

This document explains how to configure new kernel in grub2. grub users please excuse. Check below link to learn more about grub2

Ubuntu-Grub2

Edit /etc/grub.d/40_custom file and add below configuration for new menu item. Please make sure that you are not removing anything which already present in this file

menuentry 'Ubuntu, with Linux 3.0.4' --class ubuntu --class gnu-linux --class gnu --class os {
        recordfail
        insmod ext2
        set root='(hd0,1)'
        search --no-floppy --fs-uuid --set c933488a-c517-465e-9ecf-4744806b3a7a
        linux   /boot/vmlinuz-3.0.4 root=UUID=c933488a-c517-465e-9ecf-4744806b3a7a ro   quiet splash
        initrd  /boot/initrd.img-3.0.4
}

c933488a-c517-465e-9ecf-4744806b3a7a is the UUID. replace this ID with yours. For more information about UUID, wikipedia is the good source.
Use below command to find the UUID

# blkid

Update your grub configuration

# update-grub

Reboot with new kernel

Now reboot your machine. Once you boot with new kernel, execute uname -a in your shell to find the kernel version.

Linux pranavam 3.0.4 #1 SMP Sun Sep 4 12:28:48 IST 2011 i686 GNU/Linux

Quota report using LDAP and Dict

This script will export all LDAP information including current quota usage. You should use quota dict for quota storage

http://wiki1.dovecot.org/Quota/Dict

LDAP attributes

1. givenName
2. sn
3. uid
4. mail
5. quota

This is the way how script will work :

• Script will collect all information from LDAP database. Using NET::LDAP. http://search.cpan.org/~gbarr/perl-ldap/lib/Net/LDAP.pod
• Script collect data from quota dict for using perl DBI
• Script stores all information in a file 
• Script sent mail to administrator attaching the same report using MIME:Lite. http://search.cpan.org/~rjbs/MIME-Lite-3.027/lib/MIME/Lite.pm

#!/usr/bin/perl

# This script will export LDAP information including current quota usage.
# Install NET::LDAP, DBI, MIME::Lite for running this script.
# You have full freedom to modify this script. This will help me to improve the usage.
# Please feel free to reach me on praveen.velu84@yahoo.com

use Net::LDAP;

use DBI;

use MIME::Lite;

# Create a file for storing data

open (MYFILE, '> /tmp/quota_report.csv');

# Modify connection settings of dovecotdict database

my $dbh = DBI->connect("DBI:Pg:dbname=dovecot;host=localhost", "dovecot", "paassword", {'RaiseError' => 1});

my $sth = $dbh->prepare('SELECT * from quota where username = ?') or die "Couldn't prepare statement: " . $dbh->errstr;

$ldap = Net::LDAP->new("localhost");

# Modify your LDAP connectivity.

$ldap->bind("cn=admin,dc=example,dc=com", password=>"secret");

$mesg = $ldap->search(filter=>"(&(mail=*)(objectclass=posixAccount))", base=>"dc=example,dc=com");

print MYFILE "User_Name;First_Name;Last_Name;Email;LDAP_quota(MB);Quota_Usage(MB);No_of_messages\n";

@entries = $mesg->entries;

foreach $entry (@entries){

                $name = $entry->get_value("uid");

                $fname = $entry->get_value("givenName");

                $lname = $entry->get_value("sn");

                $mail = $entry->get_value("mail");

                $quota = $entry->get_value("quota");

$sth->execute($mail);

@data = $sth->fetchrow_array();

$usedquotamb = ($data[1]/1048576);

$quotausage = int $usedquotamb;

$messages = $data[2];

                print MYFILE $name . ";" . $fname . ";" . $lname . ";" .$mail . ";" . $quota . ";" . $quotausage . ";" . $messages ."\n"

}

close MYFILE;

# Senting mail to administrator. Replace postmaster email id with your email id

my $msg = MIME::Lite->new(

    From    => 'postmaster@example.com',

    To      => 'admin@example.com',

    Subject => 'LDAP quota report',

    Type    => 'multipart/mixed',

);

$msg->attach(

    Type     => 'TEXT',

    Data     => "Dear Sir, \n\nThis is an automated message. Please find attached User Quota Report.\n\nEmail Administrator ",

);

$msg->attach(

    Type     => 'text/csv',

    Path     => '/tmp/to_report.csv',

    Filename => 'quota_report.csv',

);

$msg->send;

$dbh->disconnect;