dorian fraser moore

Problems reading burnt ext2 DVDs

Eric Waters suggests it might be a block size issue

I've not had anyproblems with a block size of 1024, but Eric said he checked it out and 2048 was the appropriate blocksize for DVDs, so that might be it

I found your website in a google search for info on burning DVD's in
Linux. After following your instructions, I was able to nicely burn an
unmountable ext2 DVD. The problem, I discovered (through the help of
http://www.linux.net.nz/lists/NZLUG/2003/07/1243.html), is that the DVD
is burned with a sector size of 2048k, so therefore the blocksize of the
ext2 image (created with dd and mke2fs) must be 2048, *not 1024*.

So, instead of:

dd \
if=/dev/zero \ # read input for file from /dev/zero
of="ext2_file" \ # output file
bs=1024k \ # file has block size of 1024k [1 Megabyte]
count=4096 # file has 4096 blocks [4 Gigabytes]

mke2fs \
-b 1024 \ # block size
-F \ # Force [I shouldn't have to use this, but I do]
ext2_file # input file

... it should be this:

dd \
if=/dev/zero \ # read input for file from /dev/zero
of="ext2_file" \ # output file
bs=2048k \ # file has block size of 2048k [2 Megabytes]
count=2048 # file has 2048 blocks [4 Gigabytes]

mke2fs \
-b 2048 \ # block size
-F \ # Force [I shouldn't have to use this, but I do]
ext2_file # input file?

You might want to add this to the webpage so others don't burn a coaster
like myself.

Eric Waters