Tag Archive: Linux


Like most others, if you tried installing Windows 8.1 or Windows Server 2012 R2 64Bit in Oracle Virtualbox, you must have encountered the following error.

Win_VM_Error

This error occurs when the instruction CMPXCHG16B is disabled in your CPU. It is so by default in Oracle Virtualbox. The simple solution is to enable this instruction & then you should not get the error on initializing the Windows 8.1/Windows 2012 virtual machine.

To do this on your linux system first issue the following command,

$VBoxManage list vms

The above command will list all the virtual machines present. Be sure to run this command as a normal user. You won’t see a list of vm’s if the command is executed as a root. The VboxManage command is case-sensitive, keep that in mind. So make sure you use it properly as VboxManage.

Once done, copy down the vms name. In my case “Windows”.

[shuttertux@localhost ~]$ VBoxManage list vms

“Windows” {6e60906c-d449-4142-ba17-bb0424d3da3d}

Now to enable the CMPXCHG16B CPU instruction one needs to execute,

$VBoxManage setextradata “Windows” VBoxInternal/CPUM/CMPXCHG16B 1

The value ‘1’ at the end of the command enables the desired CPU instructions. Now you can go ahead successfully and install Windows 8.1/Windows 2012 64Bit in Oracle VirtualBox.

The wikipedia explains the following on CMPXCHG16B CPU instructions:

Early AMD64 processors lacked the CMPXCHG16B instruction, which is an extension of the CMPXCHG8B instruction present on most post-80486 processors. Similar to CMPXCHG8B,CMPXCHG16B allows for atomic operations on octal words. This is useful for parallel algorithms that use compare and swap on data larger than the size of a pointer, common in lock-free and wait-free algorithms. Without CMPXCHG16B one must use workarounds, such as a critical section or alternative lock-free approaches. This also prevents 64-bit Windows from having a user-mode address space larger than 8 terabytes. The 64-bit version of Windows 8.1 requires this feature.

Install Cisco Packet Tracer under Linux

Cisco Packet Tracer can be a very useful tool for learning about networking without needing to spend tons of money(infact, none). The simulator allows you to create a networking topology & then carry on your configurations & changes before they can be implemented in the real world networking environment. This is critical as you get to learn from any mistakes in simulation thus not needing your network to act as a guinea pig. Here, I’ll show you how you can install the Cisco Packet Tracer under your linux system. I would be installing it on Fedora 18.

Cisco Packet Tracer Linux

Continue reading

Ganesh Utsav 2013 – In Motion

I went all over the city to bring you the finest of the Ganesh idols. Here is my coverage of Ganesh Utsav 2013 right from the first day all the way till Visarjan. Most of the footage is shot hand-held except for a few shots. The footage was edited in OpenShot Video Editor which is a breeze to work with. The sound-track used is “Mourya Re” from the bollywood film Don. Enjoy the video. :-)

GIMP is a good free software for photo-editing. It has most of the capabilities you will require of its commercial counterpart Adobe Photoshop. What’s more with the right plugins, you can extend its capabilities. Here I’ll tell you about some GIMP plugins which will primarily be of interest to photographers. They will make your photo work-flow easier & faster.

GIMP-logo

Vignette – As the names suggests, this adds a vignette to your photo. Vignette can be used creatively to allow viewer’s eye to stay within the frame. Most of the photos will benefit from a small amount of vignette. The vignette plugin allows you to choose parameters like vignette colour, softness, darkness etc. It does its job very well.

Lomo – Want to mimic the look of a LOMO camera? This plugin will do it for you. It saturates the colour, adds a vignette(there is also an option for double vignette) & some other parameters for fine-tuning the output. Have fun!

Split Tone – Split toning is another beautiful effect. This plugins lets you select the two colours for split toning(as oppose to just two offered by most other programs) & end up with results beyond your imagination. Give this a try.

Darla Contrast Fix – This plugin aims to normalize the contrast in the photograph. With the right settings, it can make a photograph. However, this plugin requires some practice & knowledge of the parameters before one can get consistent results regularly.

National Geographic – Have you always wondered at the quality of the photos published by Nat Geo? They are sharp, contrasty & look as if edited by professionals. This simple plugin will put the same power in your hands too. This is a great plugin & as Darla Contrast Fix, this too requires practice before you’re able to get consistent results on a regular basis.

G’MIC – Stands for GRECY’s Magic for Image Computing. This is a grand-daddy of plugins. It is so packed with various image manipulation tools that I wonder even if someone will discover all of them in lifetime. Right from the basic sharpening, noise reduction to advanced like soft glow. This covers it all. And did I say, each of the tools come with several more options to fine tune the output? Yes, this is one hell of a plugin.

Off-course, there are many more plugins in the GIMP repository but these are the few I use on a regular basis & find to work properly. If you have your favourite GIMP plugin not listed here, do share it below. Will benefit all. :)

Many have been reporting problems when installing VMware Workstation 9 on Fedora 18 64 bit machines & on other distros using the newer kernel versions – 3.8* or newer. The installer reports of missing kernel header files & prompts for the same. Installing kernel-headers package does not work. This problem isn’t related to Fedora 18 but its due to Vmware guys not updating their vmware-config-tool for the new kernel releases. Before you go ahead to rectify the problem, I advise you update your kernel & its headers.

#yum update kernel* -y

#yum install kernel-headers kernel-devel -y

Reboot the system & boot into the new kernel. Fire up a shell & issue,

#uname -r

This will output you the current booted kernel version. Copy the entire line into the clipboard.

Now create a new directory at the following path,

#mkdir -p /lib/modules/your-kernel-version-here-from-above/build/include/linux/

It should look similar to,

#mkdir -p /lib/modules/3.9.5-201.fc18.x86_64/build/include/linux/

Now we need to copy the missing .h file to the location we just created. Issue,

cp usr/include/linux/version.h /lib/modules/3.9.5-201.fc18.x86_64/build/include/linux/

Now launch Vmware 9, if it still fails have a look at the pointed log file in the error prompt.

#cat /tmp/vmware-root/vmware-modconfig-3787.log

It should mostly indicate failure to build ‘vmci’ or ‘vmblock’. This is okay & one can ignore this. Hit cancel to quit the Vmware 9. Open a shell. We will now edit the vmware configuration file & disabled the entry which ensures ‘vmci’ or vmblock’ module is built & loaded.

#vi /etc/vmware/config

Find the line

VMCI_CONFED = “no” (It will be YES, make it as ‘no’)

This will cancel building of vmci module. Same can be done for vmblock.

VMBLOCK_CONFED = “no”

Now save & quit Vi editor issuing,

ESC key + :wq! + Enter Key

Now launch VMware 9 & it should launch normally. :)

Follow

Get every new post delivered to your Inbox.

Join 81 other followers

%d bloggers like this: