Wait about two days and I'll have a solution for you.
Between the 'bootloader-n900' package and a custom bootloader script, I have a backup menu I'm working on that basically boots the N900 with almost nothing, mounts the rootfs as read-only, and backs it up to the SD card.
Then, restoring is easy - just use flasher to restore the rootfs.
(the opt-fs will be more interesting; I assume we can just restore the rootfs via Flasher, reboot into the custom bootloader, and restore the opt-fs from there.

So far, I actually have the script running fine - but its missing any sort of 'progress' meter for DD.

-Rob

which device(s) do you dump with dd@RobbieThe1st?
can u explain your solution, i am also interested in the dd solution.

greets

Great. Does the device appear stable and in order? no weird kinks anywhere like a missing menu item or crash?

IIRC, I used "dd if=/dev/mtd5 of=/media/mmc1/backup-rootfs.img bs=4096" to back it up, then I used the flasher to restore.

Corso85: Yup, 100% stable. I haven't had a crash yet, and I've definitely put some strain on it recently - rebooted like 20+ times, loading up xterm as soon as its possible to do so, and connecting to USB at the same time.

Still, its a finicky solution. You could end up with corruption, not all that good an idea.

So, I recommend against it.
What you -should- do is use my new method, which uses a bootloader-based script to do the same thing(so we can lock rootfs and avoid suck things).

To install:
Or, get it from Here
Once you have that installed, download my script from Here, and copy/save it to your MyDocs folder.
Now, open up xterm, and run:
Now, reboot with the keyboard open.
You should see a crude menu.
From this menu, you have several options, but the most important are the last two: Backup and Restore.
I'm still working on this, so it isn't polished, but Backup works great.
You can select if you want to backup the RootFS or the OptFS, or both, and you can independantly save each to the SD card or eMMC.

The Restore option needs a bit of work, but it will do in a pinch. The main thing to be aware of is that there is a screen labeled "Select file", and it has a list of files on the drive you chose. Unfortunately, these files aren't labeled as to how to select one. The answer is that each are labeled in alphabetical order - pressing a selects the first one, b the second etc.
Now, like I said, there may be bugs.
However, I -know- it will back up properly. If you manage to screw things up and can't restore for whatever reason, keep the backups and we can fix any glitch you have.
And remember, you can always restore the rootfs via flasher!

Now, I'm not going to be around for a couple of days, but don't worry - when I get a chance, I'll work on it some more, get it all polished and nice.

P.S. If you can understand shell-scripting, go ahead and take a look at it, tell me what you think.
This is my first major undertaking in ash, and it took me quite a while to figure some stuff out.

-Rob

Sorry for the double post, but:
I've completely re-written the whole script, made it a -lot- nicer.
I think I've worked all the bugs out of it, and it should be safe to use.

I've added it, and install instructions to this page: http://wiki.maemo.org/User:Robbiethe1st

Hope it helps someone!

-Rob

hi robbie,

nice work - thx for the customized bootmenu.item.
as i have seen there might be a linking problem in your user page: BackupMenu.item fail should be BackupMenu.item correct
did you give the remote backup option via usbnet a try or just a local backup?

anyway - well done


regards - zement

Thanks.

And no, I've designed it only for local - I haven't even tried remote, on anything.

I figure its too complex for most (windows-based) N900-owners, and its going to be easier to just back it up to SD, then copy it to your HD.