Just type the following in a console window:
tar cvzf – filename.iso | split -d -b 700m – filename.iso.tar.gz.
This wil produce the following files:
Burn to CD with your favorite burner, one file per disk.
Then later if you want to restore the iso, first copy all the parts in one directory, and then type
cat filename.iso.tar.gz.* | tar xvzf –
That will give you back your original ISO.
I needed this a few days ago for a >10G backup that I wanted to put on a FAT32 external drive (maximum file size: 2G). Worked like a charm!
If you are concerned with space, replace the ‘z’ option in tar with ‘j’, and replace ‘gz’ in the filenames with ‘bz2’. Bz2 compression is usually a bit better than gz compression, but it’s slower.
And if you really want to save disk space, install the console version of 7-Zip, create a .7z archive, and pipe this trough split.