Category Archives: Linux

Everything related to Linux

Convert mkv to avi with mencoder

Command to convert mkv file to avi with mencoder in linux:

mencoder input.mkv -ffourcc divx -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=400 -oac mp3lame -lameopts vbr=3 -o output.avi

Share mouse and keyboard with multiple computers!

Recently I was working simultaneously on my desktop and laptop. A number of times it so happened that I was sub-consciously trying to move the cursor on my laptop with the mouse attached to the desktop or at other times I was peering at the document on my desktop while typing on my laptop and wondering why nothing was displayed. Then it occurred to me it’d be great if I could use the same mouse and keyboard for both the systems. Google led me to this site and I was instantly hooked to Synergy.

Synergy is Free and Open Source Software that lets you easily share your mouse and keyboard between multiple computers, where each computer has its own display.
Synergy is Free and Open Source Software that lets you easily share your mouse and keyboard between multiple computers, where each computer has its own display.

No special hardware is required, all you need is a local area network. Synergy is supported on Windows, Mac OS X and Linux. Redirecting the mouse and keyboard is as simple as moving the mouse off the edge of your screen. Synergy is released under the GNU Public License (GPL)… as described on the website.

A word of caution… I ran into problems when I was trying to share my iMac’s mouse and keyboard with a Windows XP PC. I was using the latest stable version 1.3.7 on both. Apparently the iMac’s keyboard input was not getting propagated to the Windows machine. The solution… downgrade the version on Mac to 1.3.6 1.3.6 Mac OS X Universal and everything will run fine.

 

Reinstall Grub

Boot your Helena live CD
* Open a terminal – Applications, Accessories, Terminal.
* Determine your normal system partition – `sudo fdisk -l` (That is a lowercase L)
* If you aren’t sure, run `df -Th`. Look for the correct disk size and ext3 or ext4 format.
* Mount your normal system partition:

sudo mount /dev/sdXY /mnt

– Example: sudo mount /dev/sda1 /mnt
– Note: substitue the correct partition: sda1, sdb5, etc.
– Note: GRUB 2 counts the first drive (X) as “0”, but the first partition (Y) as “1”

* Only if you have a separate boot partition:

sudo mount /dev/sdXY /mnt/boot

– with sdXY being your /boot partition designation.

* Reinstall GRUB 2:

sudo grub-install –root-directory=/mnt /dev/sdX

– Example: sudo grub-install –root-directory=/mnt /dev/sda
– Note: Substitute the correct device – sda, sdb, etc. Do ”not” specify a partition number.

* Unmount the partition:

sudo umount /mnt

* Reboot.