Re: Multi Volume CD/DVDs
> ... I would like to ask what is the commonly
> practiced method of creating multi-volume disks. That is, for instance
> I need to burn a directory that has files whose combined size is, say
> 12 GB. How would one go about creating multiple ISO9660 images from it
> and then burning them on CD/DVDs.
A few years ago i was faced with the same problem and my solution
is available as open source software :
see file README
In respect to other comments i have read so far :
scdbackup does not use exotic ISO 9660 features. It produces plain
independend ISO filesystems (+RockRidge) on several CDs.
To Andy :
scdbackup is one of the off-list answers sent to Norbert Preining
about his request for a "'good' backup program".
I was reluctant to advertise my stuff as such a thing.
Ashish Rangole on the other hand asked for a central feature of scdbackup
which i am proud to present.
Worthless, of course, without mkisofs, afio, cdrecord or growisofs.
(Taking a bow)
> Is there a way that these images can themselves keep track of
> information like their position in the
> sequence, total number of images that constitute the complete dataset
scdbackup-0.8 maintains a list of checksum records (MD5) which
may be used to identify a volume of a multi volume backup. Those records
tell date, total number of volumes and sequence number of the given volume.
But this needs to read the whole media and will fail if the media is damaged.
(It's actually intended for verifying write success.)
So you will be better off with a leaflet of paper which holds the desired
information in human readable form. Paint unique, permanent ID numbers on
your media and refer to them on the leaflet. (Staedler Lumocolor pens seem
to do no harm to the surface of a CD-RW. I never tested Edding pens.)
> Also, what if the things are complicated by the existence of one or
> more files of size > 2GB.
That depends wether the affected programs got compiled with
Large File Support. I was told that mkisofs of cdrtools-2.01a19
has that feature (there are newer releases meanwhile).
> Is this a Linux only issue?
Traditional functions and data structures of the file system interface
used 32-bit signed integers (e.g. fseek got parameter long offset ).
With Linux (and others) there are compile time macros which switch
to more modern data types : _FILE_OFFSET_BITS=64 _LARGEFILE_SOURCE
> Is this an issue on 64 bit SGI IRIX systems?
I suppose that SGI's own programs do support large files while possibly
some third-party programs don't.
scdbackup's programs get compiled with Large File Support. You will
also need mkisofs with that feature (see above).
Nevertheless, when creating ISO 9660 filesystems, scdbackup can not
handle files which are larger than a single media. Therefore files >2GB
can only be backuped on DVD (scdbackup uses growisofs to write the media)
or in format afio (large file support since afio-220.127.116.11beta4).
Have a nice day :)