How to create a image in Slackware Linux

naihe2010 · 11-19-2006, 10:07 PM

when I read freenas's source code, I found some codes like this:

Code:

#Creating a 16Mb empty file
dd if=/dev/zero of=image.bin bs=1k count=18432
#use this file as a virtual RAM disk
mdconfig -a -t vnode -f image.bin -u 0
#Create partition on this disk
fdisk -BI -b $BOOTDIR/mbr /dev/md0
#Create label on this disk
bsdlabel -B -w -b $BOOTDIR/boot /dev/md0 auto
bsdlabel md0 >/tmp/label.$$
bsdlabel md0 |
     egrep unused |
     sed "s/c:/a:/" |
     sed "s/unused/4.2BSD/" >>/tmp/label.$$
bsdlabel -R -B md0 /tmp/label.$$
rm -f /tmp/label.$$
#Create filesystem on this disk
newfs -b 8192 -f 1024 -o space -m 0 /dev/md0a
#Mount this disk
mount /dev/md0a $CDROOT

And, I can't "mdconfig" "newfs" "bsdlable" commands. How to do the same thing in Slackware Linux ?

osvaldomarques · 11-20-2006, 03:46 PM

Hi naihe2010,

I don't know really what kind of use you want to do with it but, basically, in linux, you create file systems, not partitions. There are several types of fs you can create, ramfs, cramfs, tmpfs, squashfs, isofs but you also can create vfat and ext2.

First you have to create a space to be formatted as your example

Code:

dd if=/dev/zero of=image.dsk bs=1k count=18k

Then you need to format it:

Code:

mke2fs image.dsk # for an ext2 fs
mkisofs image.dsk # for a cd isofs
mksquashfs image.dsk # for a compressed read only fs
mkinitrd image.dsk # for an initial boot ram fs
mkfs.msdos image.dsk # for an msdos fs

Here, it will alert you that image.dsk is not a block device and you confirm for it to proceed.
Now, you only need to mount it with an special mount option:

Code:

mount -o loop image.dsk /mnt/<your-mount-point>

Now you can populate it with your files.

I don't know the purpose of the example you gave on bsd. If it is a boot device, there are other ways to create a bootable media. I can't say the differences because I don't know bsd.

Note. some of these file systems may need special packages, in special squashfs as they are not in the kernel tree yet.

Bruce Hill · 11-20-2006, 04:20 PM

naihe2010,

The address you entered for your website is incorrect/unreachable.

naihe2010 · 11-20-2006, 05:37 PM

Thank osvaldomarques, that is I wanted.

Thank Bruce Hill.