How to setup Linux loadbalancer using: LVS + ldirectord + heartbeat 2 on CentOS
Posted October 14th, 2009 by gnulinuxSteps to setup heartbeat-2.1.4 on centos 5.2.
In this document you will find procedure how to setup lb01 and lb02 as loadbalancer for 2 or more web servers. In this example I have used only 2 webservers i.e web01 and web02. In total there are 4 virtual servers. All four servers are virtual servers. I am using Xen as dom0.
After installing base operating system (I have installed CentOS 5.2) we need to install following packages on both loadbalancer linux boxes. As heartbeat is not available with standard packages you will need to download it.
How to convert / migrate image based vm (guest / dom-U) to LVM based vm (virtual machine)-(Guest / dom-U) using xen.
Posted July 2nd, 2009 by gnulinuxHi all, In this article we will learn how to install virtual machine on sparse file (image file) and how to migrate / move it to LVM based storage / disk. It is recommended to use LVM based partition to install virtual machines for productions environment, as you may experience performance issues if you use images (sparse files) to install virtual machine.
How to install virtual machine on image based disk ...
Configure sendmail to start logging Subject in maillog
Posted September 24th, 2010 by gnulinuxHi Friends,
In this article we will learn how to configure sendmail so that you can log "Subject" in /var/log/maillog as by default sendmail does not log Subject to maillog file.
How To Disable User Account in Linux
Posted September 20th, 2010 by gnulinuxThis short how to will show how to disable a user account under linux. This might be useful in the situation where you don’t want to permanently remove the user, but you just want it disabled and no longer able to use the system. The user will still receive emails for example, but he will not be able to login and check them out.
How To Disable User Account in Linux
Posted September 20th, 2010 by gnulinuxThis short how to will show how to disable a user account under linux. This might be useful in the situation where you don’t want to permanently remove the user, but you just want it disabled and no longer able to use the system. The user will still receive emails for example, but he will not be able to login and check them out.
Increase max_connections in mysql without restarting mysqld service.
Posted February 19th, 2010 by gnulinuxBy default in mysql database server max_connections is set to 100. This value indicates how many maximum concurrent connections mysql server can handle. If mysql reaches to it maximum (max) limit then you can see errors like "too many connections". I assume that you have enough hardware resources (Mainly RAM )to handle more connections, here with this article I will share a TIP to increase max_connections in mysql.
As we know my.cnf is default configuration file for mysqld service and by default it is located in /etc directory unless and until you have changed it.
How to install and configure AMAND backup server and client on LINUX
Posted February 16th, 2010 by gnulinuxHi all, In this article we will learn how to install amanda backup server and cofigure it to start taking backups. It is completely free and based on GPL License. we don't need to pay any license fee to use this software in live/production environment.
Steps to install amanda backup server.
- Install centos 5.2 x86_64.
- Get rpm from www.amanda.org/download.php for latest stable version of amanda server. E.g amanda-backup_server-2.6.1p2-1.rhel5.x86_64.rpm
- install this downloaded rpm using #rpm –ivh command
PostgreSQL Cheat Sheet
Posted January 29th, 2010 by gnulinux
PostgreSQL Cheat Sheet
CREATE DATABASE
CREATE DATABASE dbName;
CREATE TABLE (with auto numbering integer id)
CREATE TABLE tableName ( id serial PRIMARY KEY, name varchar(50) UNIQUE NOT NULL, dateCreated timestamp DEFAULT current_timestamp );
Add a primary key
ALTER TABLE tableName ADD PRIMARY KEY (id);
Create an INDEX
CREATE UNIQUE INDEX indexName ON tableName (columnNames);
How to setup linux loadbalancer for windows real server using ldirectord-lvs-heartbeat
Posted January 27th, 2010 by gnulinuxRequired operating system and packages
First of all install centos 5.2 with minimal packages and no gui required.
Packages required for setting up linux server as loadbalancer are as below.
heartbeat-2.1.4-4.1.i386.rpm
heartbeat-devel-2.1.4-4.1.i386.rpm
heartbeat-ldirectord-2.1.4-4.1.i386.rpm
heartbeat-pils-2.1.4-4.1.i386.rpm
heartbeat-stonith-2.1.4-4.1.i386.rpm
libnet-1.1.2.1-2.1.i386.rpm
perl-MailTools-1.76-1.el5.rf.noarch.rpm
There might me some more package dependencies but it can be resolved by installing those packages from cd.
How to compile Berkeley DB and OpenLDAP on linux
Posted January 19th, 2010 by gnulinuxHi,
Many times we need to install packages which are available only in form of source code. Or sometimes we need to install couple of different versions of packages on same server... what ever reason it may be, We can achieve this by compiling packages.
Here in this article I will just show you quick steps how to compile berkeley db and openldap.
First of all we need to download Berkeley DB and OpenLDAP. use following links to download latest stable versions.
To download Berkeley DB
http://www.oracle.com/technology/software/products/berkeley-db/index.htm...