Error 530 Must perform authentication before identifying USER in FTP

This is one of most annoying issues you face when using ftp server in Red Hat linux. The solution is very straight forward.

Open the gssftp file. It is normally located at /etc/xinetd.d

Change the line "Server_args = -l -a'

to

"server_args = -l"

Then restart the ftp server

Changing appBase in Tomcat 6

AppBase is the location where the Tom cat server searches for jsp files when called by a client. Default location is the webapps folder in tom cat home.

Changing this appBase involves bit of identifying the architecture of tom cat.

First thing you should remember is that every web application you are going to deploy should be in a separate folder. You cannot directly use that folder as the appBase. Instead you have to use parent folder.

eg: If your web application is at C:/myWebApps/firstwebApp, you have to use C:/myWebApps as the appBase.

Then calling the file C:/myWebApps/firstwebApp/hello.jsp can be done by http://localhost:8080/firstwebApp/hello.jsp


If you want to call the file C:/myWebApps/firstwebApp/hello.jsp just typing the URL http://localhost:8080/hello.jsp you have to rename the folder 'firstwebApp' with 'ROOT'.

Sorry for the lengthy description but first things first.

Then how to change the appBase.

• Open conf/server.xml file in the tomcat home foulder.
• Find the line containing Host name="localhost" appBase="webApps"
• Change webApps with the parent folder of your web application folder.
• Restart tomCat

Command line

Command line, MS DOS prompt, bash or any other command line utility should be familiar to you. AS most of people say they were used in ancient times. But still we use them, don't we? If we are using ssh what else do we have?

Need for a new generation of command lines

We all are familiar with IDEs. They provide us lot of helps when coding. Can't we create a ssh client that would help to type commands. For example when we type 'c' it should provide help listing all the commands starting with c along with their arguments.

Is there a tool like that? Or will I have to create such a tool?

Puppy Linux

I was looking for a good light weight OS to be used in virtual PC. Yesterday came across 'puppy linux'. Puppy linux is so small with only 96MB. Loads into RAM and runs pretty fast.

Still I'm studying puppy linux. Await more details.

Essential software for a PC running on windows XP

First software I would ever install would be MS Office 2007. I have used few office packages, but MS Office 2007 is unparalleled. Especially I find Onenote very useful for me.

Second software would be Mozilla Firefox. Nothing much to say. Simply it is the best. With add-ons you can do virtually anything with it.

Third is a pdf reader. If possible a pdf creater as well. Adobe is the best. Foxit reader is good as well.

Then I would go for a good text editor; ie a notepad replacement. Ultra edit is the best text editor I have ever used. Column mode, enhanced search facilities and the ability to handle very large files are specialties of UE. JEdit and Crimson editor are good free alternatives for UE.

Then it is the time for a good file manager. File manager is an enhanced version of inbuilt my computer or windows exlorer. Most file managers support two frames and tabs. Two frames helps you to perform copy and paste operartions easily and tabs give you less clutter when working with many folders. FileAnt and Explorer2 are very good user friendly free file managers.

A good compression utility is essenstial as well. 7zip, winzip and Winrar are good compression utilities. I personally prefer 7zip

Test from scribefire

Found this. Let's give a try.

It is working.

Now this text is typed off line. Let's save this. Done

When
I open it back... I can find the saved note. Also I can preview my blog
in an environment similar to blogspot. That means offline preview!
Wonderful.

Ok let's try to publish this.

Yea it is working :-)

Login to Linux without password as root

This is a very interesting fact. There is a method to log in to any Linux OS as root (super user) without a password. Further it is possible to change root password as well. Here is how to do it.

1. When you get the Grub boot loader screen select the linux OS
2. Press 'e'
3. You will be directed to another screen which is similar to Grub boot menu. Locate the entry having the word 'kernal'.
4. Press 'e' again.
5. You will be directed to a screen where you can edit the line having linux os. Type a space and single there.
6. Hit enter. Now you will come back to the Grub screen. Note that Linux Os line now has single attached to it.
7. Press 'b'

Now you will be logged in as root in to a shell.

Type passwd and hit enter. Now you can give a new root password. Enjoy...

7 easy ways to remove virus

1. If you have an antivirus program, update it.

2. If you do not have a one, install a one. I recommend Avast.

3. Right click on my computer -> properties -> system restore tab -> tick turn off system restore for all drives. This prevents virus pulling your pc to an infected state even after the virus scan

4. Reboot in safe mode

5. Run the virus scan

6. If your current virus scan is unable to destroy virus, install a new anti virus (recommend Avast, AVG). Note Uninstall the previous anti virus as running 2 anti virus programs in 1 PC may be troublesome

7. Repeat the step again with the new anti virus

Vista and XP Dual boot

In today's market; if you are buying a laptop or pc, there is a high likelihood that windows vista starter would come pre-installed. What to do with it? Here is Zyger's hints...

Understanding Vista Starter

Vista starter is somewhat a demo version of Vista. It has many limitations. To list a few.

1. Maximum memory support is 1GB
2. Cannot open more than 3 programs simultaneously
3. Has networking constraints eg. Ad hoc networking
4. It does not have aero theme which is synonymous with Vista
   

With these restrictions (especially 3 simultaneous programs max); Vista starter is not a fully fledged OS as windows xp. So we suggest to have a dual boot system with windows xp, if you really need to keep Vista with you (You have paid for it, by the way)

Here is how to have a dual boot with xp when vista is preinstalled

1. Install windows xp in a separate partition
2. Once the installation is complete, your PC will be able to boot in only windows xp. This is because; still the boot loader is not configured yet.
3. Download VistaBootPRO software
4. Install it (Note you need .net 2 framework for this)
5. Open VistaBootPRO, ignore the prompt to backup your BCD. Go to the System Bootloader tab, select "Windows Vista Bootloader" in the first section and "All Drives" in the second section and then click Install Bootloader . Next, go to the Diagnostics item on the menu bar and select "Run Diagnostics". VistaBootPRO will default back to the Manage OS Entries page and you will see that you now have entries there for "Earlier versions of Windows" as well as "Microsoft Windows Vista".

Now you got a dual boot with xp and vista. while booting the system you can select which OS to be used.

Got a new PC

Ok now you are happy. You bought a new PC with much power than your old PC. Now a new issue is on your head. How can I get all the functionality which my OLD PC had to my new PC.

Few hints....

You cannot transfer operating systems between computers. The OS while installing gets lot of details of the computer and customizes itself to suit the particular machine. So you will have to install the OS in a fresh way to suit your new PC.

You can copy all your documents and other data like photos, videos from your old PC to new PC. I suggest using a flash (pen) drive or external hard disk or re-writable CD / DVD for the operation. It is possible to fix your old hard disk to your new PC and transfer data.

Remember I told you that you can transfer your data. But I'm afraid most of the programs; especially big ones; will not be transferable from one PC to another. MS-Office is a such program. You have to install then in the new PC. Most simple programs such as Abi-word can be transferred.


So my advice is

1. Use only one Windows XP
2. Transfer your data files to your new PC
3. Install computer programs which you need to use in the new PC

Then you can forget your old PC.

Web browsers

What is the best web browser? This is a question in many people's mind. what it seems to me is that it is an issue of your personal preferences and the work you are going perform on internet.

In this blog I'm not going tell you which one is the best browser. But I would like to write down some thoughts and memories of web browsers I have played around.

Internet explorer was the first web browser I ever used. Then it was version 5 or 6. The biggest issue I ever faced was that only one page could be open per window. So while you are browsing, the desktop gets highly unmanageable after opening 4-5 web pages.

Then I came across mozilla web browser. I repeat mozilla web browser not mozilla firefox. This carried a logo of a some monster like animal (I guess it is mozilla). Mozilla was the place I came across tabbed browsing.

Then I enbraced my personal favourite mozilla firefox. Firefox has a big advantage that you can customize it with add ons as you like.

Opera is another browser I have worked. I found 2 fascinating features in it. One is it has quick dial pad. That is you can store thumbnails of web pages you frequently visit and with one click you can access them. Second one is once you open the opera window, previous tabs are open automatically.

I recently started trying google chrome. It gives you a huge space to view the web page as its various bars (addess, status, menu, tool) are minimized

Programming: the very basics

Programming is an art rather than a science. That is why some people find it very easy to grasp programming concepts while others never get it. Yes it is true, I have met some people; very bright and brainy people; who understands nothing on programming.

There is a saying in our country that you should have 3 things to study or to excel in an art.

1. You should have a born talent.

2. You should study it properly.

3. You should practice regularly.


My ancestors also say, you can miss the first attribute, that is born talent. If you follow other two hard and smart, you can sometimes outrun a born talented person who does not undergo a proper education or who does not practice regularly.


I would like to add more ideas to this. You should understand your strengths and weaknesses. Then you can go after opportunities avoiding threats. In management language you should perform a SWOT analysis on you. For an example I know someone who is an excellent programmer. He can write wonderful programs in number of languages within a very short period of time. But if you give him a blank A4 sheet and ask him to write a program, he simply can't write it. The reason is he does not remember anything on programming. But if you give him an IDE, within few minutes, he will create a masterpiece.

Dual booting : Risk free introduction to FOSS world

If you are new to the world of FOSS and willing to experiment with FOSS operating systems, yet not like to forget everything about license OS, the best thing is to have a dual boot.

I have successfully done dual boots with Windows xp / PCLinuxOS, Windows xp / Fedora core and Windows xp / Red hat Linux. Yes what you think is correct, I have changes the linux OS but not the Windows xp. There are reasons for it.

1. As Linux OSs are free, I have the total freedom of switching them as a new version / OS is coming. But due to the huge cost involved, I did not change my windows xp for more than 5 years. still I'm not willing to spend / invest for Vista.

2. Windows xp is one of my favourite OSs. It is so nice. Well done Mr. Gates


Here I'm not going to teach you step by step how to install a dual boot. You can search the internet and can find any number of articles, tutorials, cheat sheets on them.

But will give you the very abc on them.

1. First install Windows xp

2. Install linux OS and select to use an unpartitioned free space or carefully select a partition which does not have your important data to be formatted. PCLinuxOS has a new facility so that you can resize windows partitions.

3. Be sure that in the bootloader, it has included windows in the OS list. Else you will lose windows.

Good luck

Dangers of software piracy

We all know software piracy is unethical. I do agree high price demanded by software companies is also unethical. But it does not justify any attempts of software piracy. Ok that is the ethical side. Now let's talk about some practical issues in piracy.

Now most of software companies need their products registered or activated. If your copy is not legal you can't activate them. Then you have to go for cracks or keygens. I don't know exactly why but most of the cracks you find in the internet are virus or some sort of malware. And they hardly do their intended work, ie cracking the software.

So my recommendation is never go for software cracks unless you are pretty sure of the source. Even if you are sure, check the crack for viruses before executing it.

FOSS

FOSS, What to say on FOSS.... Free and Open Source Software to those who does not know the meaning :)

Let's start by figuring out why do we need FOSS? Yea, why do we need them?

First of all, they are free. Mmmm.... It does not say they come without a cost. What about the cost of downloading them? What about the cost of copying them to CD and DVD? They do have a cost.




The tiny light bulb in my brain flashes. What about ubuntu. You can get a free CD from them. They incur the shipping cost too. Great isn't it? :)


Secondly you can re-distribute them freely. In simple words, you can copy FOSS anytime you like. There are no registrations, activations, buying license etc. They are free.


Next advantage is for smart guys ( I prefer smart to Geek). If you are such a smart guy, you can customize FOSS to suit your needs and re-distribute.


Then the million dollar question. Can we trust FOSS? Will I lose my valuable documents in the PC by using software which comes free? I don't say no. There is a tendency. Here the old age adage Caveat Emptor rules. Don't know what that means? It's let the buyer beware. all that means is you are responsible for what you buy; here what you get, in the sense of FOSS.


Will list some FOSS which never let me down.

Mozilla firefox - a nice web browser
Fedora core - A linux based operating system
Mozilla sunbird - an organizer / diary / Calender
Open office - office package (just like Xx-office ; you know what Xx, right? )
PCLinuxOS - Another linux based operating system.