How to burn a CD on the Linux machines
All of the Linux machines in the Graduate Computer Lab in RLM 9.326 are equipped with DVD/CD drives capable of recording CD-Rs and CD-RWs. (You can not however record DVD media on these drives) Follow these steps to create a CD.... See also the other notes at the end of this article.
Preparing the Files
A CD-ROM can hold approximately 650 MB of data. (Some CDs, usually advertised as "80 minute" CDs, can hold 700MB or more. Check the packaging of your CD to determine its maximum capacity.) Note that the file system structures will take up some space, so the actual capacity will end up being slightly less than the theoretical capacity.
The CD-R/CD-RW drives are capable of creating audio CDs; however, we only support the creation of data CDs at this time. See the man page for cdrecord(1) for details on creating an audio CD that can be played in a normal CD player. See also the notes below on copying copyrighted materials.
Directory names and filenames will appear on the CD just as they appear on the current filesystem, so arrange your files as you would like them to appear on the CD. Note that you will probably exceed your disk quota if you try to prepare a CD layout in your home directory; instead, use the /temp/username/ directory. (For example, if your login name is userabc then you should use the directory /temp/userabc/.) Note that the files in this directory are deleted after seven days, so don't expect things that you put here to stay here; it is just a convenient place to store large, short-term files.
Generating a CD image file
Once you have the files arranged as you want them, you must build a CD image file. This file is an exact binary replica of the data as it will appear on the CD-R/CD-RW. Because the CD recording program will need to have uninterrupted, relatively high-speed access to this file, you must create it on a locally mounted filesystem. Do not create this file in your home directory or in /temp/ (both of which are NFS mounted over the network, and are subject to minor, but critical lags and lapses that would ruin a CD being recorded). Use the /buffer/ directory for this purpose.
You will use the mkisofs(8) utility to create the disk image. There are a variety of command-line options available; see the man page for details. The most common command line form that you will probably use is:
mkisofs -frvJL -o /buffer/mycd.iso /temp/mydirectory/
(In this example, the disk image is written out to /buffer/mycd.iso and the input is read from the /temp/mydirectory/ directory.)
You may also occasionally wish to use the -l flag if you intend to use the CD on Windows machines. This flag allows Windows machines to see slightly longer (31-character) filenames instead of the default 8.3 specified by the ISO-9660 CD standard. (This violates the standard, but it happens to work and occasionally be useful when working with Windows systems. Use with caution.)
Writing the CD
You must be logged in locally (i.e., physically at the terminal) to record a CD. Logging in remotely will not work. Also, you must make sure that the machine is not under a heavy load; if the CD recording process does not get sufficient CPU time and disk access to keep its buffer full throughout the process, the CD will be ruined. (The CD must be recorded in one continuous stream; you cannot pause in the middle, no matter how briefly.) You can use the uptime(1), w(1), or top(1) commands to check the current load averages. Once you are logged in, insert your CD-R or CD-RW into the drive. When you are ready to record the CD, enter the following command (choose the one that applies to you):
For CD-Rs: cdrecord -v speed=16 dev=2,0,0 /buffer/mycd.iso
For CD-RWs: cdrecord -v speed=4 dev=2,0,0 blank=fast /buffer/mycd.iso
Note that these commands assume "16x-capable" CD-R and a "4x-capable" CD-RW media. Most CD-R/RW media these days can be recorded at these speeds, but you should check first to make sure. (It will be listed on the label and/or box somewhere.) To use a different speed, change the speed=16 and speed=4 options accordingly.
Please note that recording a CD can take quite a while, and if you log out or stop the recording before it is done, the CD will be ruined. Therefore, don't start a recording session unless you know that you will be able to wait for it to finish. (For reference, a 650MB CD recorded at 1x will take a little over one hour. Calculate your own recording time accordingly. Be sure to add about 1 - 2 minutes for "session closing" [recording the "end of data" information at the end of the CD].)
Post-recording cleanup
Once you have finished recording the CD, it is very important that you delete your CD image file. The /buffer/ partition is not very big, and if you leave your file(s) in there, other people will not be able to record CDs on that machine (and they will consequently become angry at you, and your login name is right there in the file ownership field...). Also, don't forget to remove your CD! (People leave disks behind more often than you might think.)
Other notes
To copy a CD, first insert the source CD, and issue the following command:
dd if=/dev/cdrom of=/buffer/mycd.iso
Then simply follow the instructions for recording a CD from an image file given above.
Blank CD-Rs and CD-RWs can be purchased at the Co-Op and at the Campus Computer Store. They can also be purchased (at much better prices) at computer stores such as Fry's, CompUSA, Best Buy, etc., or at office supply stores such as OfficeMax.
Please note that illegally copying copyrighted software, music, movies, or other copyrighted material is a serious crime that may result in extreme punishments. Don't do it!