View source for Flash disk cloning


== SMR Flash Disk Cloning ==


Some of the SMR's now have solid-state flash memory disks, instead of the laptop, 2.5" disks used on older models.

This wiki page contains some notes describing how to write a bootable flash disk image (Slackware Linux) to a memory card. It assumes a Linux PC with USB flash card reader/writer, available as /dev/sda.

The commands below is implemented in this script Clone script. Usage:

 clone <from_file.tar.gz> <to device>
<to device> can be both the USB bus (/dev/sdx) or a IDE device (/dev/hdx)

The script will place a file .cloned-at on the Flash Disk with time information for the cloning.

If you put the Flash Disk on the IDE bus and the computer will not boot (LILO - Timestamp mismatch) then the MBR on the Flash Disk must be erased as follows:

 dd if=/dev/zero of=/dev/hdx bs=1 count=512
Writing an image

Format the disk, with one large Linux partition:

 sfdisk -L /dev/sda <<EOF
 ,,L,*
 EOF
Create a filesystem:

 mke2fs /dev/sda1 -L /
Mount the new, empty partition:

 mkdir -p /tmp/u
 mount /dev/sda1 /tmp/u
Write a previously created image from flash.tar.gz

 zcat flash.tar.gz |
 tar --extract --file - --directory /tmp/u --preserve-permissions
Create a patched lilo.conf, so that we can run LILO with the flash card mounted via USB. (This won't be necessary if the image written above already contains such a file.)

 patch -o /tmp/u/etc/lilo_usb.conf /tmp/u/etc/lilo.conf <<EOF
 *** /tmp/u/etc/lilo.conf        Tue Nov  4 21:34:44 2003
 --- lilo_usb.conf       Thu Dec 11 11:50:55 2003
 ***************
 *** 4,6 ****
   # Start LILO global section
 ! boot = /dev/hda
   message = /boot/boot_message.txt
 --- 4,7 ----
   # Start LILO global section
 ! boot = /dev/sda
 ! disk = /dev/sda bios=0x80
   message = /boot/boot_message.txt
 EOF
Run LILO:

 chroot /tmp/u lilo -v -C /etc/lilo_usb.conf
All done:

 umount /dev/sda1
 eject /dev/sda
Reading an image

Mount as above:

 mkdir -p /tmp/u
 mount /dev/sda1 /tmp/u
Read the partition:

 tar --create --file - --directory /tmp/u --one-file-system --exclude lost+found . |
 gzip > flash.tar.gz
or

 tar -zcf - -C /tmp/u --one-file-system --exclude lost+found . > flash.tar.gz
All done:

 umount /dev/sda1
 eject /dev/sda