LDAP configuration

Following is a brief introduction to configuring and adding a new directory for example.com.
To get to the module, open the YaST Control Center, and select Network Services > LDAP Server. The first option is whether to start the server on system boot. Leave this as yes and select configure.

2. The next screen allows for configuration of the LDAP server and directories. There is a navigation pane on the left. For example, selecting Global Settings > Schema Files shows the current schemes being used, and allows for schemes to be added or removed. For more in-depth information about LDAP configuration with YaST, see section 21.8.5 in the SUSE LINUX Enterprise Server Administration Guide.

3. The Databases section shows the currently configured directories. If SLES is installed with the defaults there will be one directory, site, which contains the login information for the users on this system. Create a new directory be selecting Databases in the left pane, and clicking Add Database. A new window is displayed which allows for new database information to be entered.

Fill in all the fields as follows:
Base DN: dc=example,dc=com
Root DN: cn=Admin (Be sure Append Base DN is checked. Otherwise this field would need: cn=Admin,dc=example,dc=com)
LDAP Password: Enter a new password for the directory and select the encryption method.
Database Directory: /var/lib/ldap/example.com/
This is the path to a folder where the directory files will be stored. Make sure the folder already exists.

4.Select OK and notice the new directory now shows up in the database list. Select Finish to commit the changes.
5.The new directory for example.com has now been set up. It has the base DN of dc=example,dc=com and an administrator user, cn=Admin,dc=example,dc=com. It is now ready to have additional entries added either by other clients which administer LDAP directories (such as the Network Services > LDAP Client), or by using the openLDAP command-line tools.

Burning ISO How to

Ubuntu is distributed over the Internet as CD image files, called ISOs. To install Ubuntu, you first need to burn its ISO file onto a CD. You need a working CD/DVD burner and an 80 minute (700 Mb) CD for this. This page explains how you can do it using Windows, Mac OS X, Ubuntu and Kubuntu. If the CD writing fails, try writing at a slower burn speed.
In
Windows9X/Xp/Vista

1. Download and install Infra Recorder, a free and open source image burning program.
2. Insert a blank CD in the drive and select Do nothing or Cancel if an autorun dialog pops up.
3. Open Infra Recorder, and select the 'Actions' menu, then 'Burn image'.

Select the Ubuntu CD image file you want to use, then click 'Open'.
In the dialog, click 'OK'.

XP / Server 2003 / Vista: ISO Recorder
1. Download and install the appropriate version of ISO Recorder.
2. Insert an unformatted CD into your burner. (Note: one can burn DVDs with this tool only from Vista.)
3. Open Windows Explorer, browse to your ISO file, right-click and choose "Copy image to CD".

How to MD5

The program md5sum is designed to verify data integrity using the MD5 (Message-Digest algorithm 5) 128-bit cryptographic hash. MD5 hashes used properly can confirm both file integrity and authenticity.
In terms of integrity, an MD5 hash comparison detects changes in files that would cause errors. The possibility of changes (errors) is proportional to the size of the file; the possibility of errors increase as the file becomes larger. It is a very good idea to run an MD5 hash comparison check when you have a file like an operating system install CD that has to be 100% correct.
In terms of security, cryptographic hashes such as MD5 allow for authentication of data obtained from insecure mirrors. The MD5 hash must come from a secure source (an HTTPS page) of an organization you trust. While security flaws in the MD5 algorithm have been uncovered, MD5 hashes are generally sufficient for casual use. Please refer to the secure UbuntuHashes page for the official list of Ubuntu MD5 hashes.

MD5SUM on Linux
Most Linux distributions come with the md5sum utility so installation is usually unnecessary. We are going to use the Ubuntu 6.10 Desktop install CD for the following example:
First go to the correct directory to check a downloaded iso file
#cd download_directory
Then run the following command from within the download directory.
#md5sum ubuntu-6.10-desktop-i386.iso
The md5sum should print out a single line after calculating the hash:
b950a4d7cf3151e5f213843e2ad77fe3 ubuntu-6.10-desktop-i386.iso
Compare the hash (the alphanumeric string on left) that your machine calculated with the corresponding hash on the UbuntuHashes page. When both hashes match exactly then the downloaded file is almost certainly intact. If the hashes do not match, then there was a problem with either the download or a problem with the server. You should download the file again from either the same mirror, or from a different mirror if you suspect a server error. If you continuously receive an erroneous file from a server, please be kind and notify the webmaster of that mirror so they can investigate the issue.

openLDAP on Suse Linux ES
SLES uses the open-source implementation of LDAP, called openLDAP. It is already be installed on any system that uses the default installation settings. There are only a few files that generally need to be accessed directly:
/etc/openldap/sldap.conf – The main configuration file for openLDAP. It contains sections for defining the schema of the directories, the access control settings for the directories, and the general settings for each individual directory.
/etc/openldap/schema/*.schema – Directories follow specifically defined schemes. These .schema files define several standard schemes. Referencing these .schema files in /etc/openldap/sldap.conf applies these schemes to the openLDAP directories.
/etc/init.d/ldap – The init script used to start, stop, and restart the openLDAP service.

LDAP

What is LDAP?
LDAP stands for Lightweight Directory Access Protocol. LDAP is a protocol which provides access to a compliant directory via TCP/IP. The strengths of LDAP-compliant directories include speed, simplicity, and the ability to be replicated and distributed across several servers. A LDAP directory can be used to store a great deal of information: from user login credentials to company telephone directories.
LDAP was created as a less complicated implementation of the Directory Access Protocol (DAP), and is based on the OSI X.500 standard. These standards establish directories as being hierarchical---representing the structure of an organization. There are many directories that support the LDAP protocol, each with their own benefits and drawbacks. Examples include openLDAP, the open-source implementation that ships with SLES; and eDirectory, Novell's flagship identity management product.
Directories vs. databases
The terms directory and database are often used interchangeably when referring to LDAP compliant directories. In this article, directory refers to a LDAP complaint directory, and database refers to relational databases, such as MySQL or Oracle. The two are related, in that they both store information in a structured way, but differ in their implementation. In many cases, directories and databases could both fulfill a particular need. It is important to understand the differences between the two to best determine which to implement.
The largest general difference between directories and databases is complexity. Databases are capable of storing almost any arbitrary set of information and can can be greatly customized for a specific purpose. They also provide a complex query interface, allowing for flexible searches returning customized results. Directories, on the other hand, tend to have very specific implementations that follow a strict pattern or schema. This allows them to be extremely fast, and allows for easy organization and comprehension of the data they store

LDAP concepts
Directories are viewed as a tree, like a computer's file system. This overall tree structure is called the Directory Information Tree (DIT). Each entry in a directory is called an object. These objects are of two types, containers and leafs. A container is like a folder: it contains other containers or leafs. A leaf is simply an object at the end of a tree. A tree cannot contain any arbitrary set of containers and leafs. It must match the schema defined for the directory.

Virtualisation

vVirtualisation is already gaining momentum on the server and will become common on the Desktop as well.There is Xen virtualisation which is an open source virtualisation technology which is gaining a lot of momentum and then there are virtualisation management tools to manage all the virtual machines.

Xen is open source virtualisation and has excellent performance because of para virtualisation. Its also at a lower costs and requires some services to be setup. If a customer is saving money by using Xen, they would be willing to pay for services.

Security

There are ways to secure virtual machines just like you can secure a physical machine. One of the technology is AppArmor which creates a firewall around applications. With AppArmor you can secure the virtual machine.

Linux Device driver support

The Linux Desktop survey from the Linux Foundation is now in full swing. A recent meeting of the Linux Foundation's Desktop group with the three primary vendors that now pre-install Linux also identified a number of key issues to address. And, there are always surveys online and summaries of installation tests, primarily on desktops.In all of these sources of end user pain points, we hear about how device drivers and device support ranks in the top 5 (sometimes top 1 or top 2) issues from each of these groups. As a first hand evidence of drivers as a problem, especially when dealing with the ultra-latest in hardware support. At IBM, a "tiger team" is setup to identify new hardware, work with independent hardware vendors to provide them encouragement and training on how to develop open source drivers. And, with help from the Linux community, OSDL's legal team, and the Linux Foundation after that, programs are setup to allow vendors to enter into NDA's with Linux driver writers. The goal all along has been to enable vendors to get drivers written, either on their own, or with help from the greater community of Linux driver writers and to have those drivers exist as part of the Linux kernel, available to all users when they install their Linux distribution. And, the Linux community itself has made available over 200 driver writers and 10 project managers to help create device drivers.Yes, there are holdouts like nVidia who have not embraced the open source driver path. There are challenges in the wireless space related to the FCC operational ranges for transcievers.
Difficulty connecting with some devices.
Drivers Support for some devices (Printers, WLAN, ..).There are some better comments in there, such as:
The need to manually compile drivers for external devices like a usb tv tuner (for example AverMedia provides the driver but there is no user friendly tool to install it and u need console commands knowledge and internet access in order to complete the install)
Quality drivers. Non-official drivers usually support only a subset of the full capabilities of hardware devices, and even official ones (like the Intel graphics driver, for instance) have a lot of annoying bugs.But even those are a bit vague. There is also some confusion between "devices" such as printers and scanners (many of which have pass through kernel drivers with user mode application drivers) and those that have a full kernel driver to enable their capability. Of course, that is something that the desktop group can work through over time.But my primary point here is that getting detail about *what* devices do not have support has been getting much, much harder. People need to provide information about Vendor, Product, Model number, PCI ID, USB ID, etc. to help the community identify what drivers are broken. And, when a driver is missing capability, as is alluded to in the "quality drivers" comment, the missing features need to be identified. Until we have that list of non-functioning or limited-function device, there isn't much that people can do. And, sometimes it is key to continuously let people know that features or devices are not working from release to release. The community often moves so quickly that something broken one day could be fixed the very next, and without a periodic reassessment on the functionality of the device is sometimes necessary.Oh, and before someone points out the obvious ones, yes, nVidia now has the nouveau driver, ATI has started working with the community to support their graphics devices, Intel is working towards full support of their hardware, most SCSI and SAS devices are currently supported, and there are some rough edges still with MultiPath support that are still in progress. But what else is broken? Surely these few devices can not be the substantial reason that device support is constantly on the top of the list? What other devices do not have driver support? Expose them! That is the best way to get those devices supported!!!

How to make online money

Chances are that if you are reading this blog you are interested in how to make money online. If so, I totally agree with what you are doing. One of the best ways to learn how to make money online is by reading about those who are already successful. Unfortunately, some people have a hard time finding blogs that teach how to make money online in a way that interests them.
Fortunately, you never again have to worry about this. 45n5 has put together a list of the Top 100 money making blogs. It is safe to say that visiting these blogs will give you more information than you can handle in the area of making money online.
Before you spend hours on end reading these blogs, there is one thing that you should remember. Even though learning from others is a great way to get started, you eventually have to go at it on your own. The bottom line is that you are never going to make money online by simply reading about others successes. You need to start your own career so that you can join this Top 100 list!

Freelance writing and blogging jobs

There are several options that anybody can look into. While there is no hard and fast rule for seeking the best positions, Two of my favorite places to hunt down freelance writing gigs are:
1. freelancewriting.com
2. getafreelancer.com
At freelancewriting.com, buyers post jobs ranging from business plan writing to keyword articles. Make sure that you search both the “high paying” and “low paying” boards so that you do not miss out on anything. While you will find a lot of tire kickers on this site, a few good jobs do sneak into the picture on a regular basis.
Getafreelancer.com (GAF) is quite similar to elance.com; just not as popular. The main reason that I like GAF is that you do not have to pay anything to bid on jobs. In fact, the only time that you are forced to pay is if you win a job. Even then, you are only charged 10 percent of the total winning bid. For example, if you win a project worth $100, GAF will charge you $10 and you will net $90. This may seem like a lot, but it is actually a great deal once you begin to win more and more projects.
Check out my GAF page at http://www.getafreelancer.com/users/439947.html. Although some of the contact information is out of date, it does not really matter at this point. Getting good feedback is essential if you want to get repeat jobs. Now that I am established I usually get a couple requests to bid each week from interested buyers.
Blogging jobs are often times more difficult to find. But with that being said, they are not impossible to land. Although I guest blog for three companies right now, all of them were referrals from different clients of mine. If you are interested in a blogging job, check out http://jobs.problogger.net. This is a great place to find some of the top blogging jobs with the top blogging networks.
As you can imagine, this does not even scratch the surface as far as to what is available in the freelance writing and blogging industries. Simply put, this is where I started to find jobs, and still do from time to time.

Linux Vs Windows

Flavors
Both Windows and Linux come in many flavors. All the flavors of Windows come from Microsoft, the various distributions of Linux come from different companies (i.e. Linspire, Red Hat, SuSE, Ubuntu, Xandros, Knoppix, Slackware, Lycoris, etc. ).
The flavors of Linux are referred to as distributions (often shortened to "distros"). All the Linux distributions released around the same time frame will use the same kernel (the guts of the Operating System). They differ in the add-on software provided, GUI, install process, price, documentation and technical support. Both Linux and Windows come in desktop and server editions.
IBM is a big Linux backer but does not have their own branded distribution. Currently there seem to be many nice things said about the Ubuntu distribution.Linux is customizable in a way that Windows is not. NASLite is a version of Linux that runs off a single floppy disk (since revised to also boot from a CD) and converts an old computer into a file server. This ultra small edition of Linux is capable of networking, file sharing and being a web server.

GUI

Both Linux and Windows provide a GUI and a command line interface. Windows XP has a themes feature that offers some customization of the look and feel of the GUI.
Linux typically provides two GUIs, KDE and Gnome. The lynucs.org web site has examples of many substantially different Linux GUIs. Of the major Linux distributions, Lindows has made their user interface look more like Windows than the others. Then too, there is XPde for Linux which really makes Linux look like Windows. Quoting their web site "It's a desktop environment (XPde) and a window manager (XPwm) for Linux. It tries to make easier for Windows XP users to use a Linux box."

Cost
For desktop or home use, Linux is very cheap or free, Windows is expensive. For server use, Linux is very cheap compared to Windows.
As of January 2005, the upgrade edition of Windows XP Home Edition sells for about $100, XP Professional is about $200. The "full" version of XP Home is about $200, the full version of XP Professional is $300. Windows Server 2003 Standard Edition with 10 Client licenses is about $1,100. Because they save $100 or so on the cost of Windows, Wal-Mart can sell a Linux based computer for $200 (without a monitor) whereas their cheapest Windows XP computer is $300 (as of January 2005).
The irony here is that Windows rose to dominance, way back when, in large part by undercutting the competition (Macs) on cost. Now Linux may do the same thing to Windows.
You can buy a Linux book and get the operating system included with the book for free. You can also download Linux for free from each of the Linux vendors (assuming your Internet connection is fast enough for a 600 MB file and you have a CD burner) or from www.linuxiso.org. Both these options however, come without technical support. All versions of the Ubuntu distribution are free.
You can purchase assorted distributions of Linux in a box with a CD and manuals and technical support for around $40 to $80 (some distributions may be less, others may be more). Regular updates and ongoing support range from $35 a year for a desktop version of Linux to $1,500 for a high-end server version. August 2004 Red Hat started selling a desktop oriented version of Linux for under $6 per user per year.
After the initial cost (or lack thereof) of obtaining software, there is the ongoing cost of its care and feeding. In October 2002, ComputerWorld magazine quoted the chief technology architect at Merrill Lynch & Co. in New York as saying that "the cost of running Linux is typically a tenth of the cost of Unix and Microsoft alternatives." The head technician at oil company Amerada Hess manages 400 Linux servers by himself. He was quoted as saying "It takes fewer people to manage the Linux machines than Windows machines." Microsoft commissioned a study that (no surprise) found it cheaper to maintain Windows than Linux. However, one of the authors of the study accused Microsoft of stacking the deck by selecting scenarios that are more expensive to maintain on Linux.
I don't know if there will ever be an objective measure of the ongoing care and feeding costs for Linux vs. Windows. If there were however, it would have to consider:
Dealing with bugs in the operating system
Dealing with bugs in application software
Dealing with viruses, worms, Spyware, etc.(big advantage to Linux here)
Dealing with software upgrades to new versions (both the OS and applications)
Mark Minasi makes the point (Windows and .NET magazine, March 2000) that the Linux GUI is optional while the Windows GUI is an integral component of the OS. He says that speed, efficiency and reliability are all increased by running a server instance of Linux without a GUI, something that server versions of Windows can not do. In the same article he points out that the detached nature of the Linux GUI makes remote control and remote administration of a Linux computer simpler and more natural than a Windows computer.
Is the flexibility of the Linux GUI a good thing? Yes and No. While advanced users can customize things to their liking, it makes things harder on new users for whom every Linux computer they encounter may look and act differently.

Running Linux Without Installing It

One thing that Linux can do that Windows can not, is run from a CD. To run Windows, it has to first be installed to your hard disk. Normally Linux also runs from a hard disk, but there are quite a few versions of Linux that run completely from a CD without having to be installed to a hard disk. The term for this is a "Live" CD.
Running a Live CD version of Linux is a great way for Windows users to experience Linux for the first time. Among the Linux distros that have a CD-only version are Knoppix, Ubuntu and Open SuSE). I tried SuSE Live Eval version 9 in October 2003 and had some gripes. FreeBSD, a version of Unix (rather than Linux), also has a LiveCD.
The CD based versions of Linux differ in their use of the hard disk. Some, such as Lindows, do not write anything at all to your hard disk, making it the safest and easiest way to experience Linux. The downside of this is speed (CDs are much slower than hard disks) and continuity (being able to save data between uses). Other versions, such as SuSE 9 (this is now up to v10.2), do use your hard disk (SuSE 9 creates over 200 MB worth of files). What you give up in safety, you gain in speed. For reviews of Linux distributions that run from a CD see A Taste of Linux by Jim Lynch at ExtremeTech January 23, 2004 and A Taste of Linux, Part Two by Jim Lynch March 5, 2004.
In addition to kicking the tires on Linux, a Live CD can also be used to insure that your hardware is supported by that specific version of Linux. Bootable Linux CDs are also used to recover files when Windows breaks to the point of not being able to start up. A recent Live Linux CD should be able to see all Windows files (they can read NTFS) and copy them to an external USB device or another computer on a LAN. Older CD based versions of Lindows and SuSE could not read files stored in an NTFS partition.
In October 2005 a whole new way of running Linux without installing it was introduced: Virtual Machines from VMware. Virtual machines let you run multiple operating systems on one computer at the same time. You can't beat it (virtual machines are used to run Windows on the Intel based Macs).
Using the free VMware Player you can download pre-built Linux virtual machines. Think of the VMware Player as analogous to the Adobe Acrobat Reader. Creating virtual machines costs money, but playing them does not.
VMware has been creating virtual machines on PCs for a long time. Running a virtual machine previously required their expensive software (VMWare Workstation was $200 in April 2007, only a couple years previously it cost almost twice that). Now it can be done for free. And prior to October 2005 there were no pre-built virtual machines available from VMWare, if you wanted to run Linux, you had to install it.
Now you can get a pre-installed virtual copy of Ubuntu v7.04 Server, OpenBSD 4.0 and CentOS 5.0. Even better, many pre-built Linux virtual machines come with pre-installed applications. Want to run the Apache web server and the MySQL database? Just download a VM with them installed.
For years you could have installed Linux into a new virtual machine. It is a great way to learn and experiment. However, creating a new virtual virtual machine required the somewhat expensive VMWare workstation. Now, the free VMware Server software can be used to create a new virtual machine into which you can install any operating system. You can also download new, empty virtual machines from EasyVMX.
VMWare Server has another big plus: it supports a checkpoint (a.k.a. restore point, synch point). You can take a checkpoint in your virtual machine, work on it a while and then revert the VM back to the checkpoint. All for free. How things change.
Microsoft also has free virtual machine software but there are no-prebuilt virtual machines for it. Needless to say, Microsoft is not going to provide Linux virtual machines and they make a lot of money selling Windows so they're not going to give it away. Also, their software is not as mature as VMware, not as robust and I've read that it runs slower.
Yet another way to run Linux without installing it is from a flash drive (a.k.a thumb drive, USB drive, pen drive, memory stick, etc.).
In June 2006 David Pogue wrote about Linux distros can run from a thumb drive (A Handy Tip From a Reader on Flash Drives) where the two distros mentioned are 50MB (Damn Small Linux) and 70MB. In fact, Damn Small Linux does even more tricks. It can run from within Windows! And, if you have 128MB of ram to spare, it can run completely in ram, which has got to be fast. See Linux in Windows .. Again at ghacks.net.
In November 2005, you could have purchased a 3GB MicroDrive (1 inch hard disk) with Ubuntu Linux. The drive plugs into a USB port and is fully powered by the USB port. See Taking Linux On The Road With Ubuntu at Toms Hardware. I'm not sure if this is still available.
And work is ongoing on creating portable Linux applications (as of March 2007).

Application Software
There is more application software available for Windows. Then again, there may be sufficient software for your needs.
Obtaining application software: If you buy a copy of Windows on a CD-ROM, you get no application software with it. If you buy a copy of Linux on a CD-ROM (or two or three) it typically comes with gobs of free application software. A new computer with Windows pre-installed may have additional application software, this is up to the PC vendorEach Linux distribution comes in multiple flavors, the more expensive versions come with more application software.
Application software installation: The installation of applications under Windows, while not standardized, is generally consistent. Installing software under Linux varies with each distribution and is not nearly as simple, easy or obvious as Windows. Lindows lets users install software in a manner somewhat like Windows update - applications are downloaded and automatically installed.

Virtual Machines
The most ambitious approach is to install one operating system inside another. Perhaps the most popular example of this is with Intel based Macintosh computers. Software from Parallels (Parallels Desktop 3.0 for Mac) and from VMware (Fusion) lets you run Windows at the same time as Mac OS X. In this example, the Mac OS X is referred to as the host or native operating system, it's the one that gets run when the computer is turned on. Windows is referred to as the guest operating system. This approach is called Virtual Machines. Assorted virtual machine software is available that lets Linux, Macs and Windows operate as either the host or guest operating system.
In a guest copy of Windows, running under either Linux or Mac OS X as the host OS, you can install any and all Windows programs. Somewhat like a split personality, one computer can run two (or more) operating systems at the same time. VMware was the first to market with a virtual machine product (also called VMware) for personal computers. Virtual PC, has competed with VMware for a long time. Parallels is a more recent competitor. Virtual Machine products from these companies differ in their supported host and guest operating systems.
Win4Lin is virtual machine software that only supports Linux as the host OS and only supports Windows (95, 98, Me, 2000 or XP) as the guest OS.

Viruses and Spyware
There are many types of malicious software programs. The most common types are referred to as Viruses and Spyware. Spyware has become a generic term, much like "Xerox machine" (which is taken to mean any copying machine, not just those made by the Xerox corporation). The term "Spyware" now refers to a whole host of malicious software such as worms, Trojans, dialers, keystroke loggers, browser hijackers and, of course, actual Spyware. The vast majority of all malicious software (of all types) runs on Windows. I don't know the actual percentages, but it wouldn't surprise me if it was 98% or so.
Spyware on Windows has become such a problem that Microsoft purchased an anti-Spyware software company and released their product as the Microsoft Anti-Spyware program in early 2005. As this is written the product is still in beta form, but Microsoft has stated that it will be free even when complete. In my opinion, Spyware is the worst problem effecting Windows based computers. In addition to running an anti-virus program constantly, Windows users also need an anti-Spyware program constantly running in the background to protect them.

Clustering

"Linux clusters provide supercomputer-type performance at a fraction of the expense." The same article reported that Merrill Lynch runs a cluster of 50 Linux computers. In March 2005, Forbes magazine reported that: "Linux now has become so technically powerful that it lays claim to a prestigious title--it runs more of the world's top supercomputers than any other operating system."(see Linux Rules Supercomputers by Daniel Lyons March 15, 2005).

Multiple Users
Linux is a multi-user system, Windows is not. That is, Windows is designed to be used by one person at a time. Databases running under Windows allow concurrent access by multiple users, but the Operating System itself is designed to deal with a single human being at a time. Linux, like all Unix variants, is designed to handle multiple concurrent users. Windows, of course, can run many programs concurrently, as can Linux. There is a multi-user version of Windows called Terminal Server but this is not the Windows pre-installed on personal computers.

Printer Drivers
Every computer printer ships with drivers for last last few versions of Windows (at the time it was manufactured). Running the printer on a very old or too new version of Windows may or may not work. Still, this a far better situation than with Linux which does not support as many printers as Windows. In an environment with many Linux users, shared network printers a tech support staff, this should not be an issue as you can limit yourself to well supported printers. Home users of Linux however, will no doubt suffer from the relatively poor support for printers. Stephen Manes wrote in Forbes magazine (October 2002) that "Linux printer drivers tend to handle the simplest of printing functions and leave out the rest".
User Data
Windows allows programs to store user information (files and settings) anywhere. This makes it impossibly hard to backup user data files and settings and to switch to a new computer. In contrast, Linux stores all user data in the home directory making it much easier to migrate from an old computer to a new one. If home directories are segregated in their own partition, you can even upgrade from one version of Linux to another without having to migrate user data and settings.

Linux DNS setup

Steps to follow to configure DNS:
1. Install bind packages and caching packages.
#rpm -ivh bind*
#rpm -ivh caching*
2. open /etc directory.you will find two files:
named.caching-nameserver.conf,
named.rfc1912.zone#cd /etc# ls -l named.*
3. open the first file in VI editor
# vi named.caching-nameserver.conf
at line 15 add the IP addres of your DNS server
at line 23 allow-query
{local host; 192.168.0.0/24;}
at line 32 match-client
{local host;192.168.0.0/24;}
Note : i am using 192.168.0.0 as an example network.
save the file
4. open the second file in VI editor
# vi named.rfc1912.zone
copy the lines from line 21 to line 25 and paste at the end. Edit the lines as follows :
zone "xxx.com" {
type master;
xxx.for";
allow-update {none};
}
save the file
5. Now go to /var/named/chroot/var/named
6. copy the file localhost.zone and name it as xxx.for# cp localhost.zone xxx.for
7. Open the file xxx.forand add following lines in the end.
sys1 IN A 192.168.0.1
sys2 IN A 192.168.0.2
save the file
8. #vi /etc/resolv.conf
nameserver 192.168.0.3
Note : ip address of the machine you are configuring as DNS server.
9. now start the service
#service named restart
#nslookup
enter the name and u should get the ip address as reply