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Showing posts from 2014

Word 2013 gives an error when opening a file downloaded from the web

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Today, after downloading an important attachment from my Gmail Account, I got the following error while trying to open it: Word experienced an error trying to open the file. Try these suggestions: *Check the file permissions for the document or drive. *Make sure there is sufficient free memory and disk space *Open the file with the Text Recovery converter. The solution is to right click the file then on the properties box click unblock.

Advertising a default route over BGP

JEREMY L. GADDIS , owner of  the blog at http://evilrouters.net , has written an excellent tutorial on how to advertise a default route over BGP . The most important part of the tutorial to actually advertise the default route is the following: R3(config)# router bgp 33 R3(config-router)# neighbor 172.16.34.4 default-originate R3(config-router)# neighbor 172.16.35.5 default-originate SOURCES evilrouters.net :  Advertising a default route over BGP

How strong is SSL encryption ?

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Ever wondered how strong is the SSL encryption we use everyday in our web browser and email clients (e.g Outlook, ThunderBird)? Q: How secure is the encryption used by SSL? A:  It would take significantly longer than the age of the universe to crack a 128-bit key. Understanding SSL SSL uses public-key encryption to exchange a session key between the client and server; this session key is used to encrypt the http transaction (both request and response). Each transaction uses a different session key so that even if someone did manage to decrypt a transaction, that would not mean that they would have found the server's secret key; if they wanted to decrypt another transaction, they'd need to spend as much time and effort on the second transaction as they did on the first.  Of course, they would have first have to have figured out some method of intercepting the transaction data in the first place, which is in itself extremely difficult.  It would be s...

How to solve the Blue Screen of Death when Using GNS3 on Windows 7 or 8

When you are using GNS3 on Win 7/8 and if you stop the router, you get a blue screen saying your PC ran into some problem with the following error: IRQL_NOT_LESS_OR_EQUAL Your PC will restart after this error :( After doing some research on the GNS3 forum and reading the users experience, I found 2 solutions to this problem: 1. Run GNS3 on a LINUX Distro e.g DEBIAN or UBUNTU (FYI: A Linux Distro is always more stable than Windows) 2.If you are not comfortable with LINUX then you can still use WINDOWS but make sure you run the following CISCO IOS Images according to a post (please see extract below) on the CISCO LEARNING NETWORK   by Navneet.Gaur : “These are the stable working IOS images for GNS 3. I have some of them as I own the routers. 1 Cisco 2691 Router | 2600 Series - Extremely stable      c2691-adventerprisek9_ivs-mz.124-9.T7.bin 2 Cisco 3640 Router | 3600 Series      c3640-ik9o3s-mz.124-25...

Bandwidth vs Speed

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One of my friend was having a difficult time understanding these 2 terms and was interchangeably using the words speed and bandwidth to mean the same thing where in fact speed and bandwidth are 2 different things. So I decided to write this post and make things clear :) Bandwidth IS NOT Speed Speed is generally used by consumers to refer to how fast they can download files and upload files.  Bandwidth Broadband Internet packages are sold based on their bandwidth, or the size of the "Internet pipe" that is allocated to each user. This number refers to the capacity of the "last mile" connection that connects your home to the nearest aggregation point. In other words, it is the maximum throughput that the user can get on his broadband service. Does higher bandwidth give you faster speed? The analogy of driving on the motorway will help you to understand bandwidth and speed. Imagine that you're driving on a road with 4 lanes in a car t...

Insufficient power on USB port causes clicking sound on USB External Drive

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On a Saturday night, after happily and proudly connecting my Verbatim USB 3.0 External Drive I was shocked to hear a clicking and fearful noise. I thought the drive has failed. The drive is 1 TB (2.5 inch hard disk). I had to copy some important files from the External drive to my Laptop. I switched to another USB port and guess what... my drive worked correctly J The real culprit was one of the USB ports on my laptop. (Oh My DOG, this USB port is a real B*TCH !!) “Clicking Noise does not absolutely mean that the external drive has failed.” The USB port on my laptop is not faulty – a USB mouse connected on this port works correctly. I did some research to investigate this issue. Other users got similar problem “Low voltage to a hard-drive can mimic all manner of failures.” So, insufficient power from a USB port on a laptop or pc can cause clicking noises on an usb external drive. My drive is safe. I can copy my data from it. Long live my drive J

WinRAR - Total Path and File Name must not exceed 260 characters

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Below is the message I usually get when the 260 characters limit is exceeded while extracting an archive especially if it contains lots of HTML files. This limitation is by design in Windows. WinRAR or any software is not to be blamed. On Linux you don’t have this limitation. From MSDN : “In the Windows API (with some exceptions discussed in the following paragraphs), the maximum length for a path is  MAX_PATH , which is defined as 260 characters.” I found a couple of workarounds to deal with this issue: 1.Print my favorite online pages as PDF (You can use doPDF  or online web2pdf convertors. I recommend printfriendly.com ) 2.Move the archive file (ZIP or RAR) to the root of the drive. Example, You can copy or move it to C:\  or D:\  then extract your ZIP or RAR file from there.

Traditional T9 Style Keyboard for Android

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Traditional T9 Style Keyboard for Android If you are looking for traditional keyboard on your android smartphone welcome!! I am used to the traditional style keyboard on my Nokia N73 mobile. So I find it a bit difficult to type using the QUERTY Keyboard especially on smaller screens. As solutions we have the following  apps on Google Play Store : 1. Perfect Keyboard Free - Free and Commercial Versions 2. (EvenBetter)NumberPad Keyboard - Commercial There might be other similar (FREE) apps but these two looks great. Just for your info, from Wikipedia : "T-9 , which stands for Text on 9 keys, is a USA-patented predictive text technology for mobile phones (specifically those that contain a 3x4 numeric keypad), originally developed by Tegic Communications, now part of Nuance Communications."

enable password vs enable secret vs service password-encryption

Even if you have passed the CCNA or higher certifications, there’s always something which still teases your mind and challenges your technical knowledge. I am talking about password encryption in cisco routers. I did some research and investigated it myself. From Official CiscoIOS Password Encryption Facts webpage: “To determine which scheme has been used to encrypt a specific password, check the digit preceding the encrypted string in the configuration file. If that digit is a 7, the password has been encrypted using the weak algorithm. If the digit is a 5, the password has been hashed using the stronger MD5 algorithm. ” Summary: 7 = type 7.weak encryption (reversible encryption) 5= type 5. strong encryption (MD5 one way hash encryption) enable password = plain text enable password in configuration file (show running-config) enable secret = encrypts enable password using the MD5 Hashing algorithm . Password is encrypted in configuration file (show runn...

C++ Implementation of JAVA API

Java is a programming language created by Sun Microsystems ,now owned by Oracle Corporation. One of the strength of the Java programming is that it comes with a rich set of Application Programming Interface (API). This API facilitates programming of IMAGE Processing, Sound processing etc. The standard library in C/C++ does not have any built in functions for manipulating images or sound. You have to start coding from scratch a set of functions which will allow you to accomplish this task (What a pain !!) Alternatively, you can use open-source or third party libraries. While searching for a native implementation of JAVA-like API I got NaJa and NewJ as solutions. NaJa is an open source project while NewJ is a commercial product (Trial available) What is NaJa according to the official website : "NaJA stands for Native C++ Java-like API. The Java API is is a rich, standard and quite good design object library. There is no complete equivalent usable direc...

To prevent data loss, proactively monitor your hard disk

Nice Introduction from the Acronis website: “There are three unavoidable certainties in life: Death, Taxes and Hard Disk Drive Failures.  Acronis does not have a solution for the first; however, we can make sure that your financial records, photos, videos and other items of sentimental or monetary value are protected so that you can cherish the memories and pay your taxes on time! Acronis Drive Monitor is a free tool that helps monitor your hard drive, and prevent data loss.” How? Understanding the Technology: S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) is a disk monitoring technology which can predict many disk failures. This technology is implemented on the most modern hard drives. Many hard disk monitoring software e.g Acronis Drive Monitor query this information to analyze and predict hard drive health, status, failure. Supported Hard Drives according to the Acronis website: “ With the first version of Acronis Drive Monitor, the le...

KVM: Open Source Virtualization

KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V). It consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko. KVM also requires a modified QEMU although work is underway to get the required changes upstream. Using KVM, one can run multiple virtual machines running unmodified Linux or Windows images. Each virtual machine has private virtualized hardware: a network card, disk, graphics adapter, etc. The kernel component of KVM is included in mainline Linux, as of 2.6.20. KVM is open source software. KVM is arguably a TYPE 1 Hypervisor according to this IBM blog post on virtualization: …but the truth is that  KVM  actually does run directly on x86 hardware. People assume it is a type 2 hypervisor because one of the ways that it is packaged is as a compo...

Hello World !! Welcome to my blog

As in programming, I will follow the tradition by starting this technical blog with "Hello World". I will try to share my technical experiences,challenges and solutions to IT issues. This blog will be very helpful to System Administrators, Systems Engineers, DBA, Network Engineers, IT Managers, IT Newbies (noobs) and other IT professionals.