I started building an initrd image for use with loadlin and md (I wanto to put everything under raid-0). As first step, I needed the image of an ext2 (or whatever) file system to mount via loopback device, in order to put into it all the necessary modules and so on.
First, I realised that, if any docs exist on how to use the loopback device, they are well hidden. Hints are found in the mount man page and in the Bootdisk-HOWTO, but nothing general enough. Indeed, everyone assumes that you have an image and want to mount it, but nothing is said about what to do to *create* an image from scratch. Well, the Bootdisk-HOWTO says how to do, but it does not work... It says that you just need to do dd if=/dev/zero of=/tmp/fsfile bs=1k count=nnn mount -o loop -t ext2 /tmp/fsfile /mnt and voila`. But mount refuses to mount, because it does not find a superblock. So I tried to mkfs.ext2 on the file, but to no avail: apparently mkfs is not able to work on loop devices. Moreover, the mkfs.ext2 man page is missing (I filed a bug report). Well, if you cannot suggest a better way, here is a small script that creates an ext2 file systrem image from scratch. One caveat: it uses a ram disk, so you must have enough free memory to hold all of it. Improvements welcome. ------------------------------------------------------------------- #!/bin/sh # Create file IMG of size SIZE KB, which is the image of an ext2 # file system, using ramdisk device RAM, and mount it at MNT IMG=/boot/initrd.img SIZE=200 RAM=/dev/ramdisk MNT=/mnt/initrd LABEL='initrd image' set -ex # exit on all errors mkfs.ext2 -L "$LABEL" -m 0 -v -b 1024 $RAM $SIZE mount $RAM $MNT mount $RAM $MNT -o remount,ro dd if=$RAM of=$IMG bs=1024 count=$SIZE umount $MNT mount -t ext2 -o loop $IMG $MNT -- TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word "unsubscribe" to [EMAIL PROTECTED] . Trouble? e-mail to [EMAIL PROTECTED] .