Difference between revisions of "Disk mounting"

From Noah.org
Jump to: navigation, search
m
m
Line 10: Line 10:
 
</pre>
 
</pre>
  
== losetup -- mount individual partitions in a whole disk image ==
+
== losetup ==
  
If you have a while disk image and you want to mount partitions inside that image then use `losetup` to create a loopback device for the image.
+
;Convert a VMWare split image set to a raw disk image:cat linux-server-f001.vmdk linux-server-f002.vmdk  linux-server-f003.vmdk >  linux-server.img
 +
;Find the start of partitions:fdisk -l -u linux-server.img
 +
;First partition usually starts at block 63. Each block is usually 512 bytes. Offset is therefore:echo $((63*512))
 +
;Find the start of each partition down to the exact offset byte (easier than `fdisk`):parted linux-server.img unit b print
 +
;List the next available loopback device:losetup -f
 +
;Attach loopback to a partition offset inside of a disk image:losetup -o $((63*512)) /dev/loop0 linux-server.img
 +
;Create a mount point: mkdir -p /media/adhoc
 +
;Mount the partition: mount /dev/loop0 /media/adhoc
 +
;Unmount the partition before cleaning up loop device: umount /media/adhoc
 +
;Cleanup the loop device:losetup -d /dev/loop0
 +
 
 +
== losetup -- mount individual partitions in a whole disk image ==
  
For example, if you copied an entire disk using `[[Dd_-_Destroyer_of_Disks|dd]]` like this:
+
If you have a while disk image and you want to mount partitions inside that image then use `losetup` to create a loopback device for the image. For example, say you copied an entire disk using `[[Dd_-_Destroyer_of_Disks|dd]]` like this:
  
 
<pre>
 
<pre>
dd if=/dev/sda of=disk.img bs=32768
+
dd if=/dev/sda of=disk.img
 
</pre>
 
</pre>
  

Revision as of 21:22, 31 May 2010


fdisk

This will list all the disks that Linux sees. This will not show loop devices. See `losetup` example for more information:

fdisk -l

losetup

Convert a VMWare split image set to a raw disk image
cat linux-server-f001.vmdk linux-server-f002.vmdk linux-server-f003.vmdk > linux-server.img
Find the start of partitions
fdisk -l -u linux-server.img
First partition usually starts at block 63. Each block is usually 512 bytes. Offset is therefore
echo $((63*512))
Find the start of each partition down to the exact offset byte (easier than `fdisk`)
parted linux-server.img unit b print
List the next available loopback device
losetup -f
Attach loopback to a partition offset inside of a disk image
losetup -o $((63*512)) /dev/loop0 linux-server.img
Create a mount point
mkdir -p /media/adhoc
Mount the partition
mount /dev/loop0 /media/adhoc
Unmount the partition before cleaning up loop device
umount /media/adhoc
Cleanup the loop device
losetup -d /dev/loop0

losetup -- mount individual partitions in a whole disk image

If you have a while disk image and you want to mount partitions inside that image then use `losetup` to create a loopback device for the image. For example, say you copied an entire disk using `dd` like this:

dd if=/dev/sda of=disk.img

You can later create a loop device for it and see its partitions with `fdisk` and mount those partitions individually with `mount`. Note that `fdisk -l` does not normally show loop devices. You must add an explicit path to the loop device that you want to list.

losetup /dev/loop0 disk.img
fdisk -l /dev/loop0

The previous example assumed that /dev/loop0 was free. You can you the '-f' option to automatically find a free loop device. In this example we first use the '-f' option to associate the image file with the next available loop device; then we use the '-j' option to see what loop device was associated with the file:

losetup -f disk.img
losetup -j disk.img

mounting partitions inside a disk image without loop device

It is also possible to mount partitions inside a disk image file directly with `mount` using the 'offset' option, but I have not had luck with this.

mount -o loop,ro,offset=1025 disk.img /media/adhoc

Disk recovery

Use `dd_rhelp`. This is a wrapper around `dd_rescue` that makes it easier to use.