CD Rom Drive too slow? September 20, 2005
Posted by Carthik in administration, commands, ubuntu.20 comments
If your CR Rom drive, or the CD-RW drive, or your DVD reader/writer are slower than their stated speeds for reading or writing (burning), then you may not have DMA (Direct Memory Access) enabled on the drive in question. DMA allows for faster data access for drives that support it by effectively not using CPU time for data transfer to put it really simply.
You can check if the cd drive has the option enabled by doing a:
$sudo hdparm /dev/hdc
Where “hdc” stands for the drive in question – change this if it is different on your machine (you can find out by looking in the /etc/fstab file)
If it says “dma = 0″ in the output of the command, then that means that dma is currently disabled for the drive.
You can enable it temporarily for the current session till you shutdown the computer by using the command:
$sudo hdparm -d1 /dev/hdc
This will be reset when you reboot. You can make the change more permanent by editing the file /etc/hdparm.conf, and adding the following to the end of the file:
/dev/hdc {
dma = on
}
This will turn on dma each time you boot up the computer.
Also, if you cd/dvd writer provides for some form of buffer under-run protection, you can enable nautilus to use this when it writes to the disc by using the “burnfree” option. You can set this option by doing :
$gconftool-2 –set –type boolean /apps/nautilus-cd-burner/burnproof true
Note: Your system BIOS also gets to decide how your drives behave, so check to see if the proper options are enabled in the BIOS upon boot-up.
There! Now you should be able to read/write from optical drives at the best possible speed.
How to find out the version of Ubuntu installed September 19, 2005
Posted by Carthik in commands, ubuntu.16 comments
Use the command:
$cat /etc/issue
The file /etc/issue holds the version of Ubuntu installed on your system — Useful command for those who forget (if such a thing is possible), and for those who help or support others, and want to find out what version is installed.
That’s all for now!
Find the Temperature of your Hard Drive September 18, 2005
Posted by Carthik in applications, commands, ubuntu.35 comments
So you want to know what the temparature of your hard disk drive is?
Simple:
Install the package hddtemp from the Universe repository by doing a:
$sudo apt-get install hddtemp
Later, whenever you want to check the temperature of the hard drive, do a:
$sudo hddtemp /dev/hda
where /dev/hda is the hardrive designator – which you can change if neccessary.
Save shell command history effectively September 18, 2005
Posted by Carthik in commands, guides, ubuntu.8 comments
You should know as a beginning linux user that at the terminal you can press the up arrow to visit the previous commands that you have executed. The bash shell by default saves the last 500 commands (or fewer, if there aren’t that many to save), for easy recall.
However, by default, bash overwrites the history file when you close a session, or a terminal window, saving only those commands that were used in the last session. This can be annoying if, for example you have one terminal window open, and then you open another one, and close the new one after a few commands.
By adding the following line to ~/.bashrc , you can ask bash to append to the history file, thus preventing the overwriting:
shopt -s histappend
I find this pretty useful since I have discovered it.
You can find a detailed explanation of what I tried to say above, with pictures 
at the Power Shell Usage guide. You will also find a lot of other useful tips.
Bash Command Index September 13, 2005
Posted by Carthik in commands, ubuntu.7 comments
Scared of the terminal window, or just uncertain as to what command to use and when?
Ubuntu uses the Bash shell, which is one of many command line shells (a shell is something that executes the commands you provide it with, an interface to the OS using the terminal).
An A-Z index of the Bash Command line is a handy tool for newbies like me.
Code Snippets – Lots of Goodies September 12, 2005
Posted by Carthik in commands, snippets, ubuntu.1 comment so far
Peter Cooper has set up this neat website where people can submit and save code snippets so others can reuse them. Though not entirely dedicated to linux, or ubuntu, you still can find snippets that will be useful for your day to day needs – depending on what you use your computers for.
It comes complete with tag love, so check out the Linux tag and the Ubuntu tag for starters.
Apropos – Find the Application You Need September 10, 2005
Posted by Carthik in commands, ubuntu.5 comments
Many a time you know what you want to do, and you remember installing a program that enables you to do it, but you can’t remember the name of the damn application, or the command that gets it started, right?
Well then, Apropos is for you!
Type:
$apropos
to get a list of applications with the
$apropos ftp
for starters, so you get a clue.
