How to use Cisco ASA 8.4 with GNS3

This tutorial will help you setup your CCNA, CCNP or CCIE Security Lab with Cisco ASA 8.4 which is currently supported by the latest version of GNS3.

  1. Download the source files here.
  2. Extract them and place them in the GNS3 images directory.
    For example : C:\Users\<user name>\GNS3\images\QEMU\
  3. Go to Edit -> Preference -> QEMU -> QEMU VMs
  4. Click New -> Give Name -> Set type

Continue reading…

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How to work with Cisco IOS in GNS3

As in my previous post  I have shared some working Cisco IOS for GNS3, now I am going to show you how to use those with the latest version of GNS3 which can be downloaded from GNS3’s official website. The IOS must be compatible with GNS3 and can be added to it by following the simple steps.

  1. Download GNS3 from
  2. Install it along with Wireshark, Winpcap and  Virtual Box(optional).
  3. Run GNS3.

Continue reading…

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Download Wireless Networking Study Guides

Download or purchase the CWNP Series books for improving your wireless networking skills.


Certified Wireless Network Administrator

The CWNA certification is the foundation level enterprise Wi-Fi certification for the CWNP Program, and CWNA is required for your CWSP, CWAP, CWDP and CWNE certifications. Your CWNA certification will get you started in your wireless career by ensuring you have the skills to successfully survey, install, and administer enterprise Wi-Fi networks.  The salary for Network Administrators has increased significantly since 2005, and continues to do so as the market and usage of wireless increases.

Average Salary for CWNA (US)
2005 – $69,000 2013 – $83,000

  Download E-Book

CWSP® Certified Wireless Security Professional 

The CWSP certification is a professional level wireless LAN certification for the CWNP Program. The CWSP certification will advance your career by ensuring you have the skills to successfully secure enterprise Wi-Fi networks from hackers, no matter which brand of Wi-Fi gear your organization deploys. To earn a   Continue reading…

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Working Cisco IOS for GNS3

Here I am listing all the working versions of Cisco IOS which I have tested with the latest version of GNS3.

Update as on 14th May 2018 – 

Cisco IOS GNS3 - Srijit's Blog

Cisco IOS GNS3 – Srijit’s Blog

All the IOS, IOU, Nexus and other images has been updated, checked and verified with latest GNS3 & GSN3 VM. Download here –

Feel free to download them and use them for your Cisco certifications studies.

Old ones are kept intact for your reference-

  1. 1700 –
  2. 2600 – 
  3. 2691 –
  4. 3640 –
  5. 3660 –
  6. 3725 –
  7. 3745 –
  8. 7200 (v15) –
  9. 7200p (v15) –

Mirror Links:



If you face any problem setting it up with GNS3 drop me a message and I will get back to you asap.

GNS3 is an open source (GNU GPL) software that simulates complex networks while being as close as possible from the way real networks perform, all of this without having dedicated network hardware such as routers and switches.

GNS3 provides an intuitive graphical user interface to design and configure virtual networks, it runs on traditional PC hardware and may be used on multiple operating systems, including Windows, Linux, and Mac OS X.

In order to provide complete and accurate simulations, GNS3 actually uses the following emulators to run the very same operating systems as in real networks:

  • Dynamips, the well known Cisco IOS emulator.
  • VirtualBox, runs desktop and server operating systems as well as Juniper JunOS.
  • QEMU, a generic open source machine emulator, it runs Cisco ASA, PIX and IPS.

GNS3 is an excellent alternative or complementary tool to real labs for network engineers, administrators and people studying for certifications such as Cisco CCNA, CCNP andCCIE as well as Juniper JNCIA, JNCIS and JNCIE.

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[Fix] Bricked LG Optimus L3 E400

Download all required files from : Recently I downloaded an OTA update for LG E400 but the phone didn’t start again after the update and hanged. Every time I restarted the phone it booted directly into the CMW. After a lot of google search, found a solution to fix Bricked LG Optimus L3 E400 . Here is the detailed step by step guide. All the files I needed for this fix is available under the following link. Download all required files from : Note: For me the firmware V100L is an Indian Edition. You may need to search and download versions specific to your country. Warning: Your contacts, messages may get deleted after the operation. In my case they were intact though. Steps:

  • Install the LG Driver files provided in the link.
  • Get your device into emergency mode —>remove the battery and put is back again and then press vol UP + vol DOWN + power button at once.Then wait for a vibration. Now you will see a emergency mode written on yellow background.

    Emergency Mode – LG E400

  • Connect your LG L3 to your PC using USB cable.
  • Next open KDZ updater (Run as Administrator only) and select >>  Type: 3GQCT — PhoneMode:DIAG

    LG KDZ Updator

  • Select the .kdz firmware file that you have downloaded in the KDZ file section.
  • We are ready to start the process. Click on the “Launch software update” , it will take some time to finish. If everything goes okay, then you will see a “Finished” message in log. Now your phone has been switched off from Emergency mode.
  • Next ,turn it on. This will also take some time. Don’t worry, its normal the first time.

Continue reading…

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How to integrate CCAvenue payment gateway with Resellerclub


Reseller Club

Some background details: (Please read)

  • It’s my first experience with CCAvenue payment gateway and resellerclub platform.
  • PHP is not known to me. But where there is google you can learn everything.
  • Searched extensively for any how-to regarding this integration process, but failure.
  • Coders, on freelancer sites are offering to interate at a hefty price value of INR 6000 to INR 18000. (USD 100 – USD 300). Too much for a budget startup like mine.
  • Chat Support from CCAvenue is unacceptable. You are on the waiting line forever.
  • Phone Support from CCAvenue is good but they sometimes hang up the phone without speaking.
  • Phone support means you have to spent some good amount of money for your phone bills. In my case it was STD Call.
  • Very slow response from resellerclub email support. Consider no technical support from them.
  • I was determined to set this up by any means possible. Went through the CCAvenue and Resellerclub integration manuals for atleast 15 times thoroughly.
  • Downloaded the integration kits, fired up google and Notepad and started the coding process. Linked with my domain. Bingo! It worked.

How to set it up?

So, these are the reasons why I am writing this post now. I believe in sharing knowledge with others can help our knowledge to expand. I may be wrong in my coding practice as I am extremely amateur when it comes to PHP.

Coders who are currently Continue reading…

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Solve Network Card Not Detected issue for VMWare ESXi 5.5 – DLink 528T and RTL8139DL NICs

Hello everyone,

Recently I thought of utilizing a spare system to set up my small Visualization lab at my home. It is a Core2Duo System 3 GHz with 4gig RAM and 1 TB HDD.

Huh, the moment I tried to install ESXi 5.5 from the boot disk, the installation halted saying “No compatible network card detected” and bla bla…. It was really a sad moment seeing that on my first hypervisor installation.

Oh by the way, I was using PCI NICs which were:

1. DLink 528T – gigabit NIC

2. RTL8139DL – 10/100 mbps NIC

Now this is what I did to make these two work. Continue reading…

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How to share 3g/4g connection over LAN in Ubuntu

In this post I am going to show you how to share a 3g or 4g dongle over LAN interface using ubuntu. Before beginning let me tell you what made me write this post in brief. A friend of mine purchased a TP-Link 3g WiFi router but unfortunately, his dongle was not supported. He needed WiFi by any means. As he was a Ubuntu user, I tried to use that system to connect to the Router and voila WiFi worked seamlessly.

Here is the network diagram :

Sharing 3g over LAN

Sharing 3g over LAN



  1. Install necessary packages.
    apt-get install iptables
    apt-get install dnsmasq
    apt-get install bridge-utils
    apt-get install iproute2
  2. Assign IP to eth0 interface
    nano /etc/network/interface
    auto eth0
    iface eth0 inet static
  3. Continue reading…

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Solutions for users with VoIP port blocked with Mikrotik

Writing after a long due to a busy schedule of mine. Many users worldwide have experienced a very common problem similar to mine.

VoIP port (5060) is blocked by my ISP

Before going in depth I’ll tell briefly what made me write this post. After I discovered it’s blocked, I went to my ISP and submitted all the necessary documents for the activation of VoIP. The service was activated in the evening. But later I found out the peering speed which I used to get from the ISP for p2p downloads were gone.

After contacting them, they  said that my connection is now a corporate one and peering is not applicable. Since I am a heavy downloader, I had to disable VoIP to enable peering.

Then I started to think what could be done to bypass port restriction at router level as I want to unblock it for all my PCs not just a single PC. I had a talk with Mr. Syed Jahanzaib and he suggested me to use VPN.

Let’s start our configuration process. For me its done on RB2011.

  1. Go to and copy the vpn server address, username and password.
  2. Login to winbox and then create a new PPTP Client interface from the Interface menu.
  3. Give a name : vpn. Then put in server address, username and password as shown below. Also check dial on demand nad add default route
    Continue reading…

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How to configure IPv6 connectivity with Tunnel Broker service on DLink DIR-615 router?

Configure IPv6 connectivity with Tunnel Broker service [Video Tutorial]

This tutorial shows you How to configure IPv6 connectivity with Tunnel Broker service on DLink DIR-615 router. Tunnel broker service enables you to reach the IPv6 Internet by tunneling over existing IPv4 connections from your IPv6 enabled host or router to one of our IPv6 routers.To use this service you need to have an IPv6 capable host (IPv6 support is available for most platforms) or router which also has IPv4 (existing Internet) connectivity. Our tunnel service is oriented towards developers and experimenters that want a stable tunnel platform.

The D-Link DIR-615 Wireless N Router providesbetter wireless signals for your network than existing wireless 802.11g technology. D-Link Wireless N Router DIR-615 offers decent Wireless-N performance at a very affordable price. It also has a responsive and intuitiveWeb interface. At a very affordable price, the D-Link Wireless N Router DIR-615 makes a great entry-level Wireless-N router and would satisfy most situations where a wireless network is needed. The D-Link Wireless N Router DIR-615 eliminates any excuse you might have to not move to Wireless-N (300Mbps speed cap). While the DIR-615 lacks Gigabit Ethernet and USB ports, it has everything else you’d want from a Wireless-N router.

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