Newbie introduces, and has problems

[Al Johnson]

On Wednesday 15 July 2009, François-Léonard Gilbert wrote:
> On the subject of flashing, is there any detailed explanation of the
> architecture of an image?  Are kernels and rootfs images mix-and-match?  I
> have seen that some distros only have a rootfs, others have both.   Is
> there a way to take an image of the current state of my phone before
> flashing so I can keep settings, data, etc. when flashing back?

tar.gz is for extraction to a partition on SD, and includes a kernel in the 
rootfs.
jffs2 is a filesystem image containing the rootfs, but without the kernel. It 
is for flashing into NAND.

The kernel needs the rootfs to provide matching kernel modules. If you stick 
to the kernel that matches the rootfs then the correct modules will already be 
there. If you start using other kernels you need to extract the matching 
modules-<version>.tar.gz into your rootfs. Note that after 2.6.26 some of the 
interfaces changed, so using 2.6.29 with an image built for 2.6.26 probably 
won't work well even if you do include the right modules.

For backup see:
http://wiki.openmoko.org/wiki/Backup