Change hostname in Linux box

1. Modify the the /etc/hosts file

# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1        localhost localhost.localdomain mainc mysite.com

2. Modify the /etc/sysconfig/network file

NETWORKING=yes
HOSTNAME=mainc

Mounting shared folders with VirtualBox via Terminal

1. Use the GUI wizard in VirtualBox Menu

Devices -> Shared Folders..

Remember the Folder name! (lets say "SONGS")

2. Create the mount point

$sudo mkdir <mount point>

e.g $sudo mkdir /media/songs-host

3. mount the Host folder to the mount point of the Guest

$sudo mount -t vboxsf <folder name> <mount point>

e.g $sudo mount -t vboxsf SONGS /media/songs-host

How to install yum on Red Hat Enterprise Linux 4

You will not find YUM in the Red Hat Linux 4 distributions by default. So you have to install it manually.


Follow the given steps.

[Worked fine with Red Hat Enterprise Linux ES release 4 (Nahant Update 8) ]

1. Download the RPMs

***YUM base package***
$wget http://dag.wieers.com/rpm/packages/yum/yum-2.4.2-0.4.el4.rf.noarch.rpm

***Sqlite***
$wget ftp://fr2.rpmfind.net/linux/freshrpms/redhat/7.3/sqlite/sqlite-2.8.15-1.i386.rpm

***Python-sqlite***
$wget ftp://rpmfind.net/linux/dag/redhat/el4/en/i386/dag/RPMS/python-sqlite-0.5.0-1.2.el4.rf.i386.rpm

***Python-urlgrabber***
$wget ftp://rpmfind.net/linux/dag/redhat/el4/en/x86_64/dag/RPMS/python-urlgrabber-2.9.7-1.2.el4.rf.noarch.rpm

***Python-element tree***
$wget ftp://fr2.rpmfind.net/linux/dag/redhat/el4/en/i386/dag/RPMS/python-elementtree-1.2.6-7.el4.rf.i386.rpm

2. Install the RPMs

$rpm -ivh sqlite-2.8.15-1.i386.rpm
$rpm -ivh python-elementtree-1.2.6-7.el4.rf.i386.rpm
$rpm -ivh python-urlgrabber-2.9.7-1.2.el4.rf.noarch.rpm 
$rpm -ivh python-sqlite-0.5.0-1.2.el4.rf.i386.rpm
$rpm -ivh yum-2.4.2-0.4.el4.rf.noarch.rpm

3. add the following lines to the /etc/yum.conf file

[main]
cachedir=/var/cache/yum
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1

[base]
name=CentOS-$releasever – Base
baseurl=http://mirror.centos.org/centos/4/os/i386/
gpgcheck=1

[updates]
name=Red Hat Linux $releasever – Updates
baseurl=http://mirror.centos.org/centos/4/updates/i386/
gpgcheck=1

5. Update the packages

$yum update

Cheers!!!

Pidgin + Facebook Chat

Setup Facebook chat with Pidgin is simple.

In Pidgin follow the given procedure,

1. Accounts -> ADD will take you to the "Add Account" window
           
2.  Set the following settings under the BASIC tab

Protocol     : XMPP
Username  : john.doe (if your facebook username is john.doe@facebook.com)
Domain     : chat.facebook.com
Password  :  <your FB password>

3. Click "Add"

Now you are ready to go..gud luck

Tunnelinel IPv6 traffic with Hurricane Electric Tunnel brokers

There are various mechanisms to access IPv6 resources in the internet, from your existing IPv4 only infrastructure.

One such solution is to use a tunnel broker who provides free IPv6 connectivity for the IPv4 users via tunnels.

this post will help you to create a free IPv6 tunnel with Hurricane Electric on your Ubuntu box. HE will allow the users to create up to 5 tunnels for each account.


Experience IPv6 with HE
----------------------------------------

Basic Requirements
------------------

• IPv4 connectivity
• IPv6 supported Hardware and Operating system

1. Create an account at http://tunnelbroker.net/ (free service)

2.Log in and click "create regular tunnel" from the left side bar


3. set the parameters and create the tunnel

• IPv4 end-point = Your_IPv4_address (one end point of the tunnel)

• Select the nearest or your favorite server from the given list ( this will be other end point of the tunnel that you are creating)

click "create tunnel"

4. network configuration on the host machine

• Open the /etc/network/interfaces file with your favourite editor

e.g. #sudo nano /etc/network/interfaces

• add following settings

# tunnel interface for HE IPv6 tunnel
    auto ipv6-HE
    iface ipv6-HE inet6 v4tunnel
        address <IPv6 address of the client machine>
        netmask 64
        remote <IPv4 address of the remote machine/server>
        local <IPv4 address of the client machine>
        endpoint any
        ttl 64
        up      ip -6 route add 2000::/3 via ::<IPv4 address of the remote machine> dev ipv6-HE
        up      ip -6 addr add <routed /64 address>::1:1/128 dev ipv6-HE
        up      ip -6 addr add <routed /64 address>::2:1/128 dev ipv6-HE
        down    ip -6 route flush dev ipv6-HE

4. bring the configured tunnel interface up

#ifup ipv6-HE

5. experience the IPv6 internet

• test your IPv6 connectivity with whatismyv6.com or www.kame.net

• search google with ipv6.google.com

•  Find out the rest with googling for "cool IPv6 stuff"

File Sharing with Oracle Virtual Box 4.0

If the Guest OS is Windows XP or any other Microsoft platform follow this process

1. Go to DEVICES -> SHARED FOLDERS -> add shared folder

2. select the folder from the Host OS and set the name for the share (set other options as required)

3. In the Guest OS, Go to NETWORK PLACES and then to VIRTUAL BOX SHARED FOLDERS and select the shared folder

If the guest OS is a Linux distribution like Ubuntu follow this process

1. Go to DEVICES -> SHARED FOLDERS -> add shared folder

2. Select the folder from the Host OS and set the name for the share (set other options as required / Remember the share name)

Name of the share = share_point_name

3. In the terminal enter the following command to mount the shared folder

mkdir /home/guest_share_folder (create the mount point)
sudo mount -t vboxsf share_point_name /home/guest_share_folder

Install Oracle VirtualBox-4.0 in Natty

Add one of the following lines according to your distribution to your /etc/apt/sources.list:

http://download.virtualbox.org/virtualbox/debian natty contrib deb
http://download.virtualbox.org/virtualbox/debian maverick contrib non-free deb 

http://download.virtualbox.org/virtualbox/debian lucid contrib non-free deb 

http://download.virtualbox.org/virtualbox/debian karmic contrib non-free deb 

http://download.virtualbox.org/virtualbox/debian hardy contrib non-free deb 

http://download.virtualbox.org/virtualbox/debian squeeze contrib non-free deb 

http://download.virtualbox.org/virtualbox/debian lenny contrib non-free deb

(Up to version 3.2 the packages were located in the non-free section, starting with version 4.0 are located in the contrib section)

Add the Oracle public key for apt-secure and register

wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -

The key fingerprint is

7B0F AB3A 13B9 0743 5925 D9C9 5442 2A4B 98AB 5139 Oracle Corporation (VirtualBox archive signing key) 

To install VirtualBox, do

sudo apt-get update
sudo apt-get install virtualbox-4.0

Ubuntu/Debian users might want to install the dkms package to ensure that the VirtualBox host kernel modules (vboxdrv, vboxnetflt and vboxnetadp) are properly updated if the linux kernel version changes during the next apt-get upgrade.

sudo apt-get install dkms

source: http://www.virtualbox.org/wiki/Linux_Downloads