Linux System Administration

Saving Files on Optical Media

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-o filename

Specify the filename of the ISO image being created.

Here is a sample command to include all the files from a specified directory:

# mkisofs -JrvV "disc name" -o backup.iso /home/amy

You will see a lot of output from this command. The output is useful for large file

collections to indicate an estimate of how much time remains. If you prefer not to

have this output, omit the -v option from the command.

Recording the CD-R

You can now record a CD-R with the ISO image you created. To perform the actual

recording, log in as (or use su - to switch to) root. Root permissions are needed by

the cdrecord program to access the raw SCSI layer, to modify process priorities, and

to lock buffer space into RAM to avoid swapping. CD writing has critical timing

dependencies, so it helps to keep the rest of the system as idle as possible.

If you are using a rewritable CD-RW disc in a CD-RW drive, you need to erase

(blank) the CD-RW before doing the recording:

# cdrecord blank=fast padsize=63s -pad -dao -v -eject

Some drives require the media to be ejected to reset the drive for the

next operation. Unless you have discovered that your drive does not

need this, use the -eject option, as shown here.

To record the ISO image created in the previous section, enter:

# cdrecord padsize=63 -pad -dao -v -eject backup.iso

Avoid doing any other work on a computer that is recording a ...