ClusterSSH : Working With Multiple SSH Sessions Concurrently.

Requirement -

1. General Purpose Linux OS (Mine is Fedora 16)
2. Internet Connection
3. Brain

Lately when I am doing testing with multiple Linux Servers, I need to ssh into a few servers and manage them simultaneously. And I get tired of typing same commands on the servers one after another. For example, If I want to change gateway on  all servers. I have to ssh to server , edit the config and restart network service on all servers.

I use a program called "ClusterSSH" to do that. It let you manage multiple servers via SSH concurrently.

Install ClusterSSH

sudo yum install clusterssh

Now ClusterSSH is ready on your system. Connect to multiple systems.

cssh server1 server2

Congrat! Now you can be lazy like me too. :P. I attached the screenshot to poke your interest.

CentOS5 - Installing Softwares From Installation Media

Requirement :

1. Installation Media (DVD or ISO)
2. Brain

Mounting Media DVD or ISO

Create the directory to mount.

mkdir -p /media/CentOS

Mount DVD to created directory, if you are using DVD.

mount -t auto /dev/cdrom /media/CentOS

Mount ISO to created directory, if you are using ISO.(assuming ISO file is in /root/ directory)

mount -t iso9660 -o loop  /root/CentOS-5.7-i386-bin-DVD-1of2.iso /media/CentOS

Installing softwares from mounted DVD or ISO 
Update YUM database

yum --disablerepo=\* --enablerepo=c5-media update

Search and Install Software

yum --disablerepo=\* --enablerepo=c5-media search nmap

yum --disablerepo=\* --enablerepo=c5-media install nmap -y

CONGRATULATION! 


Oops! I almost forget. Here is how to unmount the media

umount /media/CentOS