Showing posts from 2011

How to create clone of a virtual machine

After creating a virtual we can create clone of a machine which would be the eject copy of our original machine. The main profit of cloning is that it save our time to repeat whole process of creating a virtual machine if we are following a specific template.

Following command will create a clone for machine xen machine in Linux environment.

General syntax.
#virt-clone --original machine1 --name machine2 --file /var/lib/xen/images/machine2.img

--original machine1(name of the original machine of which we want to make clone)

--name machine2(name of the cloned machine which we want to create)

--file(path where we want to create the cloned machine)

machine2.img(to give extension to the cloned image) 

#virt-clone --original diskcentos1 --name distcentos2 --file /var/lib/xen/diskcentos2.img

How to install and configure Simple Machines Forum

Simple Machines Forum is one of the best open source forum available and quite easy to manage with very good features. Its new version has all the installation in the GUI mode so it creates the work more simple.

First of all download the simple machines forum from its site as in this demo i am using smf_2-0-rc5_install.tar.bz2

Extract it in the html folder or the place in the site where you want to add it. I have place it in html folder.
Rename the folder according to your need, In demo i have used name smf3.

#service httpd restart      //restart your Apache server so it can recognise it

Now go to your web browser and type you host name or IP which you are using followed by the path of the folder. As in example i have used

 You will get the welcome screen to the installation of the simple machines forum.

In this all the files are given which has to be given the write permission so that the can we can write data on them.

Define the username and password which …

How to increase the size of import in phpmyadmin(other parameters also)

PhpMyAdmin gives the import size of 2mb only and if you had to import the database of larger than this size it does not except it so we can increase the size of the import option by following steps..

go to:
#vi /etc/php.ini       //php main setting file

find the following lines and replace these by the requirements you have i am giving you an example.

Original lines:
post_max_size = 8M
upload_max_filesize = 2M
max_execution_time = 30
max_input_time = 60
memory_limit = 8M

Change it to:
post_max_size = 750M
upload_max_filesize = 750M
max_execution_time = 5000
max_input_time =5000
memory_limit = 1000M

restart your httpd service and refresh your phpmyadmin to take effect.

How to install phpMyAdmin in Linux(Redhat or equivalent)

PhpMyAdmin is very important thing for any DBA or System admin as it gives full execess to our Mysql database as well as php configuration. The best part is it has GUI mode for handling all the related issues.

First install all the reated files to run Mysql, php, Apache

#Yum install apache
#yum install php-mysql
#yum install mysql-server

configure your Apache web server( If you have any problem regarding that you can look in my post "How to configure Apache wb server")

check in the /etc/httpd/conf.d that there is php.conf file is present

start all the required services

#service httpd start
#service mysqld start

Download the required phpMyAdmin interface from the net(just google phpmyadmin download u will get it)

After downloading it uncompress it

#tar -xjvf php.......(depending upon the version u downloaded)

move this folder to your web directory in which your site is located and remane it to your likings as i have done php.
move to the folder and open the configuration file…

How to install openfiler

Openfiler is Linux based kernel which runs on anaconda also, here are the steps to install openfiler, i have installed it in through VmWare but same process will work in physical system also.

*boot the openfiler

*check your CD media if you want

*after that boot loader will start

*you will set a welcome screen ->next

*select your keyboard type

select automatic if you want openfiler to do default setting else manual for doing user define disk spacing,iam choosing manual.  

*you will get the disk setup menu

 *using new add new mount points according to your requirements

*add swap memory also in this  and required fields

*click yes to confirm it

*if you have DHCP configured use that to assign IP or you can enter manually by going to edit 

*enter the IP and network mask which you want to assign 

*Do rest of setting as you have your network 

 *select your region

*select yes to confirm it

*enter the password for the openfiler

*next to confirm it

*system installation will star…

How to install or configure Xen(Linux virtualization package)

Xen is the most famous virtualization package used in the world today, it is very powerfull and quite simple also. It can do almost all the virtualization work needed according to industry standards, It is used in clustering ,cloud computing etc...

To install it by yum use the following commands
#yum install kernel-xen virt-manager              //kernel-xen is used to install Xen kernel, virt-manager is used to give gui mode to perform all the virtualization tasks

To install it by GUI mode follow this sequence
application-> add remove hardware-> virtualization-> optional packages-> apply

After performing these tasks we have to make the xen kernel as our default kernel so tha next time when we boot the system it runs on the xen kernel. To do the virtualization we need to have the linux kernel follow these steps.

#vi /etc/grub.conf
do the following changes in the file

wq!          //write and quite the file

Reboot the system so that xen kernel can be boo…

How to configure cluster using Conga for redhat

The setup of conga was told in the earlier posts in this we will configure conga for our two systems which i am using as test cases.
First of all your two systems should be able to ping each other by there host names and ricci service should be started on each node of the system which you want to add in the cluster.

After this follow the following procedure and you should be easily able to configure a cluster..

open your luci in web browser and enter the username and password

This is the main screen after you log in the luci

Select add as system to add systems in the cluster

Add the system name and password of the systems you want to add in the cluster

Submit the systems and after that confirm it by clicking OK

In the manage systems you can see that your system are properly added or not, as in example given by both the systems added by me are shown in the bottom.

Go to cluster and select create a New Cluster

Enter the name of the cluster you want to create, add the hostnames of the systems w…

How to create Network bonding in Openfiler

Openfiler is an OS which can easily bond the network interfaces with each other so that multiple NIC cards of the storage can have a single IP. The main use of this is that our multiple NIC cards can have single IP and in case of any failure in any of the NIC card we can still access our storage in smooth form, we don't have to assign IP again to storage if there is any card problem.

Go to systemSelect bonded interfacecheck the N/W cards you want to bond togetherContinueGive a new IPIPNetworkActive Back UpNo preference Restart the network on the terminal of Openfiler.

Intoduction about Openfiler

Openfiler is one of the best storage OS available in world today, it gives GUI tool to form SAN/NAS (storage area network/network area network). It can also configure raid of any version.The LUN(logical unit no) can be created by it, the best thing about this storage OS is the it is open source and absolutely free.
For test environment it is best, as it can do all the work done by the paid storage systems also if there is any problem regarding storage it can full fill that..

How to install conga(Redhat clustering package)

Conga is a very advance tool used to do clustering of Redhat systems. it gives a whole GUI to configure systems in all the posssible ways...
following are the steps to install and access conga

#yum install ricci          //install this package first.
#service ricci restart      //start its service.

#yum install luci        //install luci package.
#luci_admin init        //to set the password of the luci service.
#service luci start     // it will start the service and give you the address from where you can access the luci or conga.

for example: https://localhost.localdomain:8084
put this address on the web browser and access it.

default username is admin and password is which you have set of luci.

How to change root password if you forget it

There are cases when we forget the root password or any body has changed it and you are not able to login in this case you can go into single user mode and change the password of the system.

1. when system is booting and kernel version is shown press e to edit.
2. again press e, tahn it will give you option to edit the boot sequence.
3. enter 1 or 'one' in the end of kernel entry and boot the system by pressing b.
4 system will open in command prompt and use command passwd to enter new password for system.
5. reboot the system and use the new password.

How to configure DHCP(Dynamic host control protocol)

DHCP is used to give ip to the system at booting time< the main advantage of this server is that, we don't have to manually configure ip's of the systems. it allocates the ip with in the range defined and can also allocate a particular ip to particular system every time by bonding its ip to mac address of that system.

#yum install dhcp*       //to install package
#cd /usr/share/doc/dhcp-3.0.5         //go to main directory
#cp -rf dhcpd.conf.sample /etc/dhcpd.conf        //copy configuration file in new location

#vi /dhcpd.conf
line 4  subnet  netmask      //enter your network conf

comment line no 7,8,10,11,12  if you dont want to do any special settings

line 21     //enter the range of ip which you want to give

line 29,30     //if you want to bond any ip with m/c than use this

#service dhcpd restart
#chkconfig dhcpd on

#dhclient         //to give ip to a system using dhcp

How to install RedHat Enterprise linux using Custom setttings in Vmware

In this we will install the Linux system by doing the custom settings of our system and not following the express settings.
Follow the images and you will be able to configure your system, make the changes according to your need.

Click on new virtual machine.

Chose "I will install the operating system later" than next

Select the Linux as your operating system than the vendor which you are using.

Set your machine name and location where you want to store it in system.

Select the amount of hard disk you want to give to the virtual machine.

click next after checking all the details are right.

Set the ram size which you want o give to your machine.

You will come up with a blank machine with define settings. Now go to "Edit virtual machine settings".

Go to the CD/DVD and after that select the use ISO image file in right side. browse to the location of the ISO image of your Linux than ok.

Than Power on the machine, the installation will start.

Select your language.

if you have inst…