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Uninstalling GRUB Boot loader:

July 18, 2009 1 comment

  1. Format the Linux partitions to create unallocated space, if you haven’t already. You can find a walkthrough on how to do this under External Links listed below.
  2. Change the BIOS so that your computer boots your CD drive first.
  3. Insert the Windows XP disc and reboot. It may take a few minutes to load.
  4. Select ‘Recovery Console’ by pressing ‘r’.
  5. Select the Windows system to log on to. The default option is ‘1’.
  6. Press enter to bypass the administrative password prompt.
  7. Type fixboot and press enter.
  8. Type fixmbr and press enter.

    Hope these will fix the MBR. J

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Categories: Linux/Unix, Windows Tags: , , ,

OpenSSL Upgradation Procedure:

April 23, 2009 Leave a comment

Every linux operating system comes with a OpenSSL version. But if you want to upgrade it to the lates version then follow the following steps:–

[ steps described above is tested on CentOS 5 (Stable) ]

Steps for upgradation of OpenSSL:——

  • Remove the previous versions of OpenSSL using the following command:

#rpm -erase –nodeps openssl

  • Fetch the latest version of openssl from http://openssl.org/source. [Latest version is openssl-0.9.8k]
  • Unzip the tar file to /usr using the following command:

#tar -zxvf -C /usr openssl-0.9.8k.tar.gz

  • Move to the /usr/openssl-0.9.8k directory

#cd /usr/openssl-0.9.8k

  • Install the OpenSSL using the following commands:

<#./config shared

#make

#make test

#make install

  • Link the new files using the following commands:

#cd /lib

#ln -s /usr/openssl-0.9.8k/libssl.so.0.9.8 libssl.so.0.9.8b

#ln -s /usr/openssl-0.9.8k/libssl.so libssl.so.6

#ln -s /usr/openssl-0.9.8k/libcrypto.so.0.9.8 libcrypto.so.0.9.8b

#ln -s /usr/openssl-0.9.8k/libcrypto.so libcrypto.so.6

#cd /usr/lib

#rm /libssl.so

#rm /libcrypto.so

#ln -s /usr/openssl-0.9.8k/libssl.so libssl.so

#ln -s /usr/openssl-0.9.8k/libcrypto.so libcrypto.so

#ln -s /usr/local/ssl/include/ /usr/include/ssl

#cd /usr/include

#rm -rf openssl

#ln -s /usr/local/ssl/include/openssl openssl

  • Rerun ldconfig
  • Perform the following steps:

#cd /etc

#rm ld.so.cache

Open the ld.so.conf file in vi editor and add the following lines:

–         add /usr/local/ssl/lib

–         add /usr/local/lib

Run ldconfig.

  • Change the Environment Path Variable

Open .bash_profile file in vi editor

#vi /root/.bash_profile

Add the following line before export PATH

PATH=$PATH:/usr/openssl-0.9.8k/apps

Save the file end exit from vi editor.

  • Reboot.
  • Done

the symbolic file name may be different depending on the operating system and different version of OpenSSL.

OpenSSL: Introduction

April 9, 2009 Leave a comment

OpenSSL is an open source implementation of the SSL and TLS protocols. The core library (written in the C programming language) implements the basic cryptographic functions and provides various utility functions. Wrappers allowing the use of the OpenSSL library in a variety of computer languages are available.
OpenSSL is based on the excellent SSLeay library developed by Eric A. Young and Tim J. Hudson. The OpenSSL toolkit is licensed under an Apache-style licence, which basically means that you are free to get and use it for commercial and non-commercial purposes subject to some simple license conditions.

Versions are available for most Unix-like operating systems (including Solaris, Linux, Mac OS X and the four open source BSD operating systems), OpenVMS and Microsoft Windows.

FIPS 140-2 Complience:

OpenSSL is one of the few open source programs to be validated under the FIPS 140-2 computer security standard by the National Institute of Standards and Technology‘s Cryptographic Module Validation Program.
[Note: FIPS stands for Federal Information Processing Standard]

Present Version:

openssl-1.0.0-beta1 [ Works under FIPS mode as weel as NON-FIPS Mode (Beta Version) ]

openssl-0.9.8k [Works under FIPS mode as well as NON-FIPS mode (Stable Version)]

openssl-fips-1.2 [ Works Under FIPS Mode ]

The other version of the setup files, documentations and other informations can be obtained from http://www.openssl.org/

Never Upgrade any Software!


Every year we see that various software companies release several software. Some of those software are so useful, that, we forget that, they will also need to update or upgrade.

For example, Nero. After opening the software in your machine you can see the version of it. It should show 6.x.x or 7.x.x or others. Right? Now, just Google the ‘Nero’. You will find, it is running 9.x.x version in the market.

Take another example, Adobe Acrobat Reader. We use this software for reading the PDF files. Now, open it. What version is it showing? 5? 6? 7? Or 8? Now, again Google the ‘Adobe Acrobat Reader’. It is running version 9 man!! What are you doing?

Go online and upgrade all these software. Open Nero’s website. Just a minute….what is it showing? The setup file of 9.0 version of Nero software is 370.5 MB???  Lol! Are they mad? If the setup is near about 400 MB, then what will be the size, if it installs??? Believe it or not, but it is 1.03 GB!!! Yes, from my personal experience, I am telling you. How horrible!!

In their site, they are saying that this time, Nero has become more user friendly and bla..bla..bla… But, in practical, if you see them, you will be more upset. What had they done? Is this our that Nero? It have become more user ‘foe’ly!  Not only Nero, but take any software.. Adobe Acrobat Reader, DivX, iTunes, Power DVD, Adobe Photoshop etc… you name it! These all are our everyday usable software. Not even software, now a days Operating Systems are also becoming monsters. Windows Vista? The os from Microsoft Corporation? Also have tested Windows 7. The same problem.

Now, lets take a small tour over the cons of these upgrading of softwares.

1. More and more Space: They want more AND more space every day. Previously, I have given an example of the Nero. Now, look at this table:

Name of the Software Previous / Most Used Version with Size Most recent Version with Size
Nero V6.x (<100 MB) V9.x (370.5 MB)
Adobe Acrobat reader V5.0 (<10 MB) V9.0 (>26 MB)
DivX V4.0 (0.7 MB) V6.8 (19.8 MB)
iTunes V4.1 (19.1 MB) V8.0 (65.6 MB)
Power DVD V1.5 (2.6 MB) V8.2 (76 MB)

These are the setup file sizes. Now, after installing, they occupy spaces like this: Nero 9.x = 1.03 GB, Adobe Acrobat Reader 9.0 = 230 MB, DivX 6.8 = 50 MB, iTunes 8.0 = 75 MB (without Quick Time, with Quick Time 100 MB). So, what will you do to your hard disk?

2. Unnecessary Functions: 99.9% of the users of Nero have a primary objective: burning a cd or dvd.  But, in the 9.0 version, you will find several tools that you will never use. For example, the Nero Home. I am sure that, you will never use it, if you have used the Windows Media Center once. More over, they give, a ‘Photoshop’-like software which is much harder in order to use the original Adobe Photoshop. You will find more applications like Nero Media Player. The ‘worst’ media player I (probably, you also!) have seen ever. Some times they provide some more ‘visually’ beautiful user interface (Eg. Nero 9), which looks great but works keen. They not only fail to do the job in time, more over pressures on the hardware of the computer which turns to our next point.

3. High Requirements: Windows Vista said that it will require at least 512 – 768 MB of RAM; however, 1GB is the best for the lowest requirement. Windows 7 has raised a step higher. It is demanding minimum 1GB of RAM. However, they said 2GB of RAM will be a good configuration in case of lowest RAM configuration. It was only the demand of RAM. Now, there remains more hardware: Processors, Hard Disk Space, Mother board, Optical Drive etc. Adobe’s latest Photoshop CS4 says of minimum requirement of 512 MB of RAM. But, in practice, I myself found, 1GB works good instead of 512 MB. But, if you guys could remember, the CS2 version had recommended requirement of 512 MB of RAM and, I myself had experienced, 320 MB was more than sufficient for it. My Intel 845GVSR motherboard with P4 2.4 GHz Processor ran the application very fast!

4. Customers are tester: When you buying a software, they will ensure in 1000 ways that, the software has been tested 10,000 times and rated “best value” by some ‘XXX’ magazine! You also look at that and think good of it and become the ‘bakra’. Coming back home, when you start installing it, the lines of problem starts. And until the software company provides a ‘patch’ or ‘update’, the problem persists. I think because of this since 2001 till today the Windows XP is providing ‘Service Pack 3’, ‘security updates’ and other ‘useful updates’. Not only XP, their last OS Vista had received a ‘Service Pack 1’ in 2008 after launching it in mid 2007. So, why will you buy new software, which has not been tested? Why don’t you use the previous versions of those software?? Here comes our last point.

5. Expensive: While Nero’s original burning software initially was used to given away with the CD-Writers at free of cost, the latest Nero 9 will cost you around US$200(probably). If you had purchased Adobe’s Photoshop CS2 or CS3 previously, then also, you have to buy it with near about US$1000(probably) with some US$100 discount. WHY? Why should I buy these software-monsters with 1000 bucks??

So, from the next time, before upgrading any software or OS, think twice. Don’t just follow the crowd of ‘latest versions’ and buy them. Apply your brain, is there really any need to buy a new software version? Can the Nero 9 burn ‘scratched’ discs?? You know the answer: No. Then why do you buy / upgrade it expending both your Income and the Internet Bandwidth??? Rather learn to use alternatives. Open Source Products. For example, In case of Vista os, use Fedora Core / Ubuntu / Cent OS…. These are FREE, OPEN SOURCE and FREELY UPGRADABLE Os which covers the solutions of all the problems stated above. Try to use ‘FoxIT Reader’ v2.3 (current) 2 free of cost with 3MB setup file size having all the features of Adobe Reader 8 and 9. Use VLC media player. This is also another open source media player software that plays nearly all types of files.  Yes, it is true, that, VLC is upgrading every month, but, that does neither require lots of internet bandwidth nor 100s or 1000s bucks as it is free and the latest version 0.9.8a (probably) has the less than 20 MB setup file; which will replace iTunes, DivX and Power DVD. So, apply your brain and think again before any software/os upgradation.

Linux: Mail Server

April 3, 2009 2 comments

Electronic mail (e-mail) is one of the popular services available on Internet hosts. E-mail software comes in two parts: a mail transport agent (MTA), which physically sends and receives mail messages, and a mail user agent (MUA), which reads messages and prepares new messages.

sendmail’s configuration file /etc/mail/sendmail.cf in Fedora and /etc/sendmail.cf

The sendmail mail transfer agent, you can use the mail command to compose and send a mail message to any user account on your Linux system. As a test, compose a message and send it to yourself.

For example,
mail edulaney
Subject: Testing e-mail
This is from my Linux system.

.Cc: but leave that blank.

After ending the message, the mail user agent passes the message to sendmail (the mail transport agent) for delivery to the specified address. sendmail delivers the mail message immediately.

To verify the delivery of mail, type mail to run the mail command again and read the message. Thus, the initial sendmail configuration file is adequate for sending and receiving e-mail, at least within your Linux system.

Categories: Linux/Unix, OpenSource Tags: ,

LINUX: Introduction


A free, Unix-compatible, 32-bit operating system developed in 1991 by Linus Torvalds while at the University of Helsinki in Finland.
Strictly speaking, Linux is the name of the operating system kernel, the central part of the operating system that manages system services, but many people use the name to refer to the complete operating system package, including utilities, editors and compilers, games, and networking components. Many of these important elements are actually part of the Free Software Foundation’s GNU Project, and others have been written and released by volunteers.

Linux is supported and distributed by companies such as Red Hat Software, Caldera Software, Workgroup Solutions, Walnut Creek Software, and S.u.S.E. of Germany. With the increasing use of Linux in the corporate world, several major companies have announced some level of support for the operating system, including Hewlett-Packard, Silicon Graphics, Sun Microsystems, and Intel, and several major applications packages have been ported to Linux,

Linux: SAMBA


If you rely on Windows for file sharing and print sharing, you probably use Windows in your servers and clients. If so, you can still move to a Linux PC as your server without losing Windows file-sharing and print-sharing capabilities; you can set up Linux as a Windows server.

When you install Linux from DVD-ROM, you also get a chance to install the Samba software package, which performs that setup. All you have to do is select the Windows File Server package group during installation.

  • Configuration file for samba – /etc/samba/smb.conf
  • Samba user’s file – /etc/samba/smbusers

Commands:—

  1. nmblookup: This command returns the IP address of a Windows PC identified by its NetBIOS name.
  2. smbadduser: This program adds users to the SMB (Server Message Block) password file.
  3. smbcacls: This program manipulates Windows NT access control lists (ACLs) on shared files.
  4. smbclient: This is the Windows client, which runs on Linux and allows Linux to access the files and printer on any Windows server.
  5. smbcontrol: This program sends messages to the smbd, nmbd, or winbindd processes .
  6. smbd: This is the SMB server, which accepts connections from Windows clients and provides file-sharing and print-sharing services.
  7. smbmount: This program mounts a Samba share directory on a Linux PC.
  8. smbpasswd: This program changes the password for an SMB user.
  9. smbprint: This script enables printing on a printer on an SMB server.
  10. smbstatus: This command lists the current SMB connections for the local host.
  11. smbtar: This program backs up SMB shares directly to tape drives on the Linux system.
  12. smbumount: This program unmounts a currently mounted Samba share directory.
  13. testparm: For checking the correctness of Samba Configuration.
  14. winbindd: This server resolves names from Windows NT servers.
Categories: Linux/Unix, OpenSource Tags: ,