How to Solve Zero Length File Problem in Linux’s Ext4 File System

By Tom Patrick

The ext4 (fourth extended) is a journaled file system of Linux that has many benefits compared to its predecessors, such as support for backward compatibility, large file system, delayed allocation, etc. However, the delayed allocation feature sometimes poses problems for the Linux system. The Linux system based on ext4 file system may encounter inconsistencies in the files in case of a power surge. To overcome this behavior, you should take appropriate corrective measures. However, if no method employed by you is successful then you should use a third-party Linux recovery software to do the needful.

Consider a scenario wherein you are working on a Linux system. Suddenly, there is a power loss and the system shuts down abruptly. When the power is restored, you switch on the system and find that the files that you created just before the crash are showing zero bytes.

Cause:

The most possible cause for such behavior is the delayed allocation feature. What happens is when a file is closed after creation, the data blocks are allocated for the file after a minute or so. Because of this, the metadata of the modified file will show zero bytes as its size. The data allocation is done after the delayed allocation is over. Hence, in the case of a power surge the new file is considered as an empty file.

Resolution:

To resolve the issue, you can use the following methods:

Mounting the file system using “data write-back”

Using three patches designed for ext4 file system: The three patches (bf1b69c0, f32b730a, and 8411e347) enforce any file with delayed allocation will be allocated immediately when a file is created.

Mount the ext4 file system with the nodealloc mount option

Mount the system with the data=alloc-on-commit option: This would ensure that all blocks that had delayed allocation would be allocated and moved to disk before a commit takes place.

However, if you still are not able to recover the lost files then you should use a third-party Linux recovery software to perform data recovery for Linux system. Such read-only tools are able to recover lost data without overwriting the original data.

Tom Patrick is a magazine editor currently researching on linux recovery

Web Hosting and Technology

By James Koh

One of the more common things about the whole web hosting is that there is a lot of technology that is behind it and this is one of the things that you need to be looking at when you are trying to choose a web hosting company. This is the most important thing that you need to look at, what kind of horsepower is going to be placed under the whole bonnet of your online experience?

Whether or not you need something that is small or something that is really large, all you need to look at is not only how much power is going to be placed there, but also the kind of quality that you need to be looking at as well. Technology and web hosting is actually something of a good partnership – something that is unavoidable in this industry, and the thing you need to be looking at is the server.

The server is really in all, a networked machine that is a lot like a desktop PC, only more powerful. In fact, the server would need to be plenty more powerful and this is because of the fact that sometimes, a single server has to power a few websites and this can run up to the scale of a hundred or even a few hundred websites – if this is a shared server hosting service that you have signed up on. One thing that you need to know is that there are plenty of servers out there, and how they are set up would determine the price you are paying for.

For one thing, a server would normally have a multi chip layout, which would mean that it has several chips daisy chained within the motherboard to make the server fast. RAM and virtual memory are also very important factors in the whole game, because of the massive amount of data that would be coming in and out of the server. There is also the whole concept of the network server, which is the core of the machine, and the machine would need to have a speedy networked that can far exceed the normal 1000MBPS Ethernet cards that you get on normal desktops.

It would also need to have an internal switch board with plenty of network interfaces, supporting a variety of OS’s. Normally, a server is usually WINDOWS or LINUX based, and this is because of their reliability and their efficiency. These are some of the aspects of the kind of technology and software that you might come to expect when it comes to the whole game of servers and web hosting. This is also the checklist you need to know – having some sort of industry knowledge will really help you to choose and make a correct choice of the companies as well as the sort of hardware you might want to need for the kind of services that you are going to be using online. With this information on hand, your web hosting experience would go by just that little bit smoother.

Vodien Internet Solutions provides all-in-one web hosting packages. Find out more details about their Singapore web hosting packages at their website.

5 Tips to Help You Have Great Skype Calls

By Meghan Burton

Are you having some trouble with popular VoIP program Skype but you have no idea how to fix it? If you’re not entirely tech savvy, you may be struggling and tempted to give up on it before you’ve even begun. Don’t worry! Here are solutions to five common problems. These are all easy solutions that anyone can understand and implement.

1. Bad Call Quality

The most common cause of poor call quality on Skype is when two users are running different versions of the program. The codecs will not be compatible which leads to echoing, lost voice packets, and general difficulty. It’s easy to fix this; each of you needs to update your own program. Just navigate to the main website and download the newest version. Alternatively, you could click on “Help” and “Check for Updates” in the Skype menu. If that option greys out, there are no updates. If there are, the program will guide you through installation of them.

After installation, check to see if the situation has improved. Skype is regularly improving on its codecs and you should always update for the latest one.

2. Call Quality Fluctuates Even After Updates

Check your internet quality. Are you doing something else online, like downloading or uploading a large file? Do you have a very low speed connection to the internet? These issues can combine to lower your call quality. Unfortunately if your internet speed fluctuates, there’s nothing you can do, but you can try not to download or upload files while you are chatting on Skype. This includes browsing large websites that may have excessive use of flash.

3. Webcam Picture Is Blurry

If your webcam looks dark, check that it’s securely connected to your computer and installed properly. Try opening it in its native program (after closing Skype) and troubleshooting from there first because that program may recognize more issues than Skype will. Turn more lights on so that the lighting is more central. Very few webcams will provide good quality video in a video call, but you can improve it with even, bright lighting.

4. Webcam Isn’t Working at All

First, check that Skype is recognizing your video. Go to Tools, Options, and then choose Video Settings under “General”. You should see an image of yourself. If you don’t, first check that no other program is using your video. You won’t be able to do both. If it still doesn’t work, again ensure that your version of Skype is fully updated. Update your webcam drivers by going to your manufacturer’s website and downloading new ones for your model. Sometimes older webcams struggle with Skype.

5. How Do I Block Someone?

Just like any instant messaging type service, Skype unfortunately has its fair share of spammers. If you receive inappropriate message or invitations to video calls, you naturally want to take the next step and block those users from accessing you again. Blocking is easy. Just right-click on the person’s name from the instant message or the call and choose “block this person” from the menu.

If you’re having a lot of problems or you simply don’t want others to view when you’re on Skype, you can also go invisible. This will mean that only you can initiate calls and instant messaging conversations because everyone else will see you as logged out. In order to do this, click on Skype at the top, then hover over online status. Invisible should be one of the options.

The Skype website is a fantastic place to investigate if you have more tech knowledge or are having a different problem. I hope these tips helped!

Meghan Burton is a professional copywriter. She recommends Octavia IT Services for business VoIP phone systems.

Ubuntu and Debian Security Applications Review

By Bob Parkinsons

Securing servers from potential attacks is of utmost importance in today’s economic climate. This article is a personal review of some of the best applications I have reviewed recently to secure my own server as well as others. This document contains applications which may or may not fit every situation to properly secure Internet facing systems. But it does use entirely open source and free host based software, So they will run without the need for expensive external hardware.

When reviewing existing security policies a few factors need to be accounted for first. These being performance, stability and overall use of system resources. Use this to determine the necessity for each of your own requirements. Instead of just pushing all of the suggested on to a single server. As some applications reviewed are not always entirely interchangeable with the others mentioned.

That being said we’ll start with Apache the Worlds most popular Web Server.

Mod Security

Without doubt one of my personal favorite Apache modules is Mod Security. Although it does require registration to download and is not entirely free without restriction. Mod Security is an invaluable Web Application firewall that deters lots of the scum and random bots floating around the Internet today. According to the Mod Security website over 70% of all attacks carried out on the web today are done on the web application level. Which is highly relevant since a single compromised web site can often leak thousands if not hundreds of thousands of passwords and user credentials in just a single compromise.

Pros

Mod Security has a very strict rule-set that is capable of blocking many types of web application attacks most of which can be found in the guidelines set out by the OWASP top 10.

Cons

The default rules can break functionality of Web applications at first. But it can be fixed if you can find the offending rules by viewing log files and commenting those rules out. Common things that may happen is that users are unable to login or some other functionality such as a custom search may break.

Snort

The next very interesting application is Snort the commonly known defacto standard in intrusion detection. Snorts job is to monitor networks while being as light weight as humanly possible. As to not consume to many system resources and slow down the users of the systems it may be running on. What really makes snort unique however is that it has heritage of being a very stable and robust IDS with both open source rule-sets and more advanced commercial rule-sets which are available via subscription.

Pros

Lightweight and flexible, Trusted and stable.

Cons

The free rules available have a lot to be desired when compared to the subscription rules.

AIDE

AIDE the file integrity checker can be used to create hashes of files or directories and is a generic replacement for the older Linux application trip wire. If an application has been modified without consent a simple cross reference via an image disk can reveal insights quickly as to which files may have changed in the process. By providing SHA1 hashes or other algorithms. It is therefore very useful for analyzing the exact cause of a vulnerability in the event of a possible intrusion and in many respects can be considered a root-kit detector without all the fancy bells and whistle like our next application.

Pros

Supports custom algorithms and makes up for where trip wire and others once failed.

Cons

Lack of documentation to properly implement and utilize for less experienced users it can be a concept you may give up on quickly. (I don’t blame you but it’s worth it.)

RKHUNTER

Another good Root-kit detector is RKHUNTER and works very much the same as AIDE but is more specifically a root-kit detector in that it scans all the usual locations where it would make sense for root-kits to hide on a Linux system or where they have historically been stored.

Pros

Very in depth and has support for a wide range of common root-kits.

Cons

By default on debian and ubuntu it flags a false positive for gawk, awk and a few other directories but I believe this to only be a false positive.

FAIL2BAN

Fail2Ban helps block out automated and often brute-force queries by bots or potential attackers over SSH that make too many incorrect log-in attempts.

Pros

By automatically banning bots not only do you protect your system from compromise but also help keep performance of the server at more optimal levels.

Cons

I’ve locked myself out temporarily before by not setting the threshold high enough and forgetting what password I used. As long as you don’t do that you should be fine.

Choose the right Web host

While this is not an application I believe that just as important and a major factor in keeping your web server secure is to choose the right web host and environment for your needs. While their are many cows, daddy’s, gators and other sharks trying to add 1 & 1 together in the 5$ or less discount hosting war. Take some time to reconsider what you are paying for and if you can afford it pay that little bit extra to get the benefits of a well known Secure Hosting provider when ever you can.

Installing Programs in Linux – It’s No Longer Difficult

By S Austin

There are quite a few myths that are still common today about the Linux operating system. One of these myths is that programs are very difficult to install.

There was a time in Linux when you had to do something called compiling a program. This involved going to the terminal and manually installing all of the files. If you did this incorrectly, the program would not load. If you needed another program installed to make this one work, you would have no idea what to do. You had to do intensive research to make sure you had all the dependencies installed. It really a serious pain and much too difficult for even an expert computer user.

This misery is still remembered by many who will tell others that installing programs in Linux is simply too hard to do. Today, after about a decade of improvements (which in computer years is quite a bit) installing programs in Linux is easy. In fact, it might be easier than what most people are used to with their current systems.

Most versions of Linux have some sort of package manager. This means that a group of people have checked certain programs to make sure they work, maintain all the updates for you, and make sure all the dependencies will install when you want to put an application on your computer.

In Ubuntu, you open the Applications menu and click on Add/Remove. Search for the program you want to install. Check a box. Then hit Apply Changes. That’s it. As you can see, this is a very simple process. To remove the program you just uncheck the box and hit Apply Changes and it’s gone. That’s easy enough for almost anyone to do. Additionally, you know these packages and programs are safe for your computer since a human being has manually approved them for your computer.

Whether using Linux or your operating system of choice, make sure to get the best business web hosting available. Don’t take chances with your business website.

How to Use Your Palm Pilot With Ubuntu

By Linda McDermott

Palm Pilots can work with Ubuntu. Learn which program you will need and how to use this to install software to your device.

If you are using Ubuntu, there are times where you can’t use older hardware since it was never ever made for Linux. One older popular piece of hardware is the Palm Pilot. While you might not expect something like this to work, it will with your Ubuntu installation.

There is a program that comes with the distribution called Gpilot. If you don’t have this, it can be installed from the repositories depending on if you have a Debian based distribution. Otherwise you will have to manually install the software to get it to work.

Gpilot is an open source program that was written so that devices like the Palm Pilot and Ubuntu could interact.

Under System and Preferences you can find a program called PalmOS Devices. This is what you need to do in order to set up your Palm Pilot to be recognized with your system. You will need to select the port that your hardware is plugged into. Once you have successfully done this, you can use Gpilot in order to install software to your machine.

Unfortunately there is not a graphical user interface for this program so you have to use the terminal. Open the terminal and type in “gpilot-install-file” followed by the file that you want to install and press enter. You will then have to hot sync your data with your Palm Pilot which will install the software to your device.

A second way of installing software if you do not like doing it this way, is to get an old Palm SD card assuming your computer can read this type of data. You can drag and drop the files you need to install from your computer onto the SD card. For most things, you Palm Pilot will recognize this data. It can be read off the card or copied over the hard drive on the device which generally helps the application run a bit faster.

I enjoy writing articles and reviews on many subjects, I enjoy sharing my personal experiences with family and home experiences. I also enjoy reviewing products, enjoy my latest reviews on what you need to know about choosing a kitchen towel bar and suction towel bar for your home.

Using Gnome Do – Quickly and Easy Launch Applications

By D. P. Robinson

Gnome Do is an add on that you can use with the Gnome graphical user interface. In design it’s very similar to Mac OSX’s quicksilver. It will allow you to quickly launch applications, run terminal commands and do searches both within your desktop as well as on the internet.

One of the fascinating things about technology, and especially technology that relates to computers and software, is that you are continuously expanding the number of tools you have, as well as increasing the amount of information your are producing. This is the age of information, but that is just a short step away from information overload and this is why tools that help you find, administer and easily use both the information you need and the applications to run it, are essential. The down side of all this technology advance is that keeping tabs on all you do, all you produce and all that you need, becomes more and more difficult. This where tools like Gnome Do come to the rescue as they have been developed with the idea of making life easier – and we can all do with a bit of that.

Gnome Do comes with an extensive set of plugins to help you perform many tasks and manage applications including use as search tool, music player, file browser, dictionary, file organizers and many more.

To get Gnome Do check with your distributions repositories. If using Gnome on your distribution, it’s highly likely that the Gnome Do package will be there. It is in the Ubuntu and Debian repositories if you can’t find them elsewhere.

Once installed, you are ready to go. The default to bring up the Gnome Do interface once it’s open is to use the “Windows Key” + Space. There is an option to make this whatever you want since some older computers do not have the “Windows” or Super key.

Once you hit the keyboard shortcut, just start typing. If you hit G, applications that have a G in their title will start showing up. You can also type in the type of application you want. If you type in Browser, your web browser regardless of it’s name will show up. Eventually you will get so fast with keyboard shortcuts, you will be launching applications this way as opposed to point and click.

It also has a few other features. You have the option of typing in a phrase and searching from different popular websites. You can type up some thoughts then copy it to be pasted elsewhere. You can even put in mathematical expressions and use Gnome Do as a quick and easy calculator.

D.P. Robinson enjoys writing about the outdoors, camping and outdoor cooking stove, amongst other things. His latest site provides information and resources on Outdoor Stoves.

Fixing “Mounting Unchecked Fs” Linux Boot Error

By Allen Sood

Like every other operating system, Linux computer also contains a system or boot volume, which is used to boot your system. Boot device is one on which all the boot files and Linux operating system are installed. In some cases, you may encounter boot errors while trying to start Linux-based computer. This behavior may occur due to missing or damaged boot files. In such cases, Linux system refuses to boot and you can not access the data stored on your Linux hard drive. It leads to critical data loss and needs Linux Data Recovery.

When you try to boot your Linux computer, you may receive the following warning message:

“EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended”

After the above error, when you run ‘e2fsck’ utility, you face further error messages that resemble the followings:

• TivoMaster:/var/tmp$ e2fsck -y /dev/hda7 e2fsck 1.06, 7-Oct-96 for EXT2 FS 0.5b, 95/08/09 e2fsck: Bad magic number in super-block while trying to open /dev/hda7

• The superblock could not be read or does not describe a correct ext2 filesystem. If the device is valid and it really contains an ext2 filesystem (and not swap or ufs or something else), then the superblock is corrupt, and you might try running e2fsck with an alternate superblock:

e2fsck -b 8193

This behavior of Linux operating system renders all your data inaccessible. In order to access your valuable data, you need to identify the cause of this problem and perform Data Recovery Linux by resolving the problem.

Root of the problem

This problem may occur after improper system shutdown without unmounting the root file system. After this, the root file system may get damaged and you will face the above stated problem.

Resolution

You can sort out this problem by formatting the hard drive and reinstalling Linux operating system. After formatting, you need to restore data from the current backup as it removes all the data from hard drive. However, if the backup is not available, Linux Recovery becomes essential.

Recovery is possible using advanced tools, known as Linux Data Recovery software. These software are designed to scan damaged hard drive using powerful algorithms and extract data that can not be accessed normally. They perform absolute recovery in a safe and easy way.

Stellar Phoenix Linux Data Recovery is the most effective tool that insures perfect recovery in all cases of data loss. The software is developed to recover data from Ext4, Ext2, Ext2, FAT32, FAT16, and FAT12 file system volumes. It works well with all major distributions of Linux operating system, include Debian, Mandriva, SUSE, Red Hat, Fedora, and Ubuntu.

Allen a student of Mass Communication doing research on Linux recovery, Linux Data Recovery software And Ext3 Recovery.

It’s that time of the year again, the spring release of the latest Ubuntu distro, 10.4, Lucid Lynx! It’s always very exciting to be one of the first users of the latest Ubuntu offering, and this time proves to be no exception. The latest features are fresh and exciting and we will outline some of the highlights below.

• Greater support for nVidia graphics drivers
• more seamless integration of social networking services like Twitter and Facebook
• removal of HAL from boot process to speed startup
• The latest GNOME environment for the default version of Ubuntu
• Kubuntu features KDE SC 4.4
• New themes and wallpapers are also added
• Ubuntu One file synching
• Ubuntu Enterprise Cloud is updated
• Ubuntu One Music Store will be unveiled
• Linux kernel 2.6.32
• Mozilla Firefox browser default search engine changed to Yahoo!

It certainly looks like this update to the most popular Linux distro is more than just minor changes, and more profound improvements to this great package are arriving.

Get your copy of Ubuntu today!