*really* backing up an n800?
 

so... I've been using an n800 (although not the same one- see below) for about a month and a half now. while I really like the device, I have one major issue:

is it in any way possible to access/mount/image/backup the onboard (not sd card) memory *without* installing the 3rd party init.fs bootmenu package?

I've been hacking away at this thing off and on, installing programs and changing stuff in /etc and various hildon config files, and a couple times now I've edited the wrong file the wrong way or installed an unstable program and caused the n800 to hang or crash on reboot. I solved those by reflashing, but that gets real old real fast.

I've been looking into ways to fully backup the n800 (or at least mount the internal memory on another machine so I can dd it), but I'm not finding any good solutions. the backup program that's provided by nokia is a joke as it doesn't actually backup any programs (much less /etc), searching on the forums lead me to init.fs, but installing that completely bricked my n800 (black screen, wouldn't boot, wouldn't charge, wouldn't reflash, wouldn't anything)... thankfully I was still within my 30 days return period so I was able to swap it for the one I have now.

it's kinda gotten to the point where I'm almost afraid to use it, at the very least, I'm very leery of installing anything or changing any settings anymore for fear of it hanging and me having to reflash it and lose everything again.



so I pose this question: is there any way I can get at the onboard memory on this thing without installing another program? do people have instructions on like building a cable for the serial port? would that even work? is my only option to keep buying (and potentially bricking) n800's till I get one where init.fs suceeds?

Re: *really* backing up an n800?
 

Just create a tarball of the rootfs?

Re: *really* backing up an n800?
 

Yes, since OP asked only about backup, this is good suggestion. The hard part with tarball is how to restore it :-)

If one intends to restore backup as is, it is possible to create jffs2 image directly from rootfs and such image is flashable via Nokia linux flasher over USB.

See http://www.internettablettalk.com/fo...3348#post33348
or search this forum for sumtool, mkfs.jffs2 and possibly also nandwrite, flash_eraseall

Re: *really* backing up an n800?
 

Sounds scary but I believe it is just coincidence. Either the HW was really faulty or the "wouldn't reflash, wouldn't anything" part is not true. initfs flasher reflashes just initfs partition which may indeed render device temporarily unbootable, but in such state reflashing is still possible via Nokia flasher (just like when flashing bad linux kernel which is run even before initfs). While I understand that your experience is pretty discouraging, I still suggest to try to install bootmenu again.

Re: *really* backing up an n800?
 

If I do say so myself I am really good with backups and have one of my home computers backing up all my machines each night via rsync (much faster and only backs up the files that have changed).

When I got my N800 I added a script to back that up too. I set my home router to always issue the IT the same IP every time it connects via WiFi (also makes things easier to connect to for other things). Each night the script pings the IT and if it's online will SSH to it and backup securely via rsync, this backs up the entire tablet including any cards loaded.

I also added a few more things, using hard links on my backup box I can keep weeks of backups using a fraction of the space and if the IT is offline for more than 10 days then I get an e-mail each night until it gets backed up :p

Re: *really* backing up an n800?
 

when I installed init.fs, I followed the instructions that came with it, chose dropbear, etc. it then attempted to reboot but apparently died in the process. it wouldn't turn on no matter how long I held the power button (no Dpad light or anything), and plugging it into the charger would not display the 'charging' icon on the screen. I know the ac adapter and battery were good because I charged the battery ahead of time before I started, and tested them later before I returned everything to the store.

in any event, since I couldn't turn it on, I couldn't reflash it. and yes I tried leaving it out overnight with and without the battery.

Re: *really* backing up an n800?
 

I use rsnapshot, which copies over the network with rsync.
With rsnapshot you can configure daily/hourly/whatever backups and it only stores the changes, then you can restore from any backup point.

rdiff-backup works similarly, but I've not tried it yet.

Re: *really* backing up an n800?
 

I'll look into that. the thread you link to seems to imply I need to boot from an sd card first though, which AFAIK requires installing init.fs, which is exactly what I'm trying to avoid.

??

Re: *really* backing up an n800?
 

I'm not sure how this would help me though if the tablet is borked and hanging on the splashscreen or something. unless I can get unrestricted access to the onboard memory from another machine, any other solution seems to require booting the tablet to some runlevel or another to run a restore program.

... unless you mean there's a way to convert that rsync into a flashable image I can use with the flasher program.

Re: *really* backing up an n800?
 

if I could get a version of the flasher capable of ripping and re-writing the rootfs, that would be good enough. can the nokia/linux/mac version of the flasher program do this out of the box?

Re: *really* backing up an n800?
 

Well, it is better but not strictly needed. When backing up live system you may end with some additional runtime garbage in the image but it doesn't hurt, better keep the system quiet when backing up. Also even with live system you are supposed to mount it again somewhere (like /opt) before backing up, don't use '/' path directly.
Well, no, even the stock initfs can boot from mmc but you need usb flasher to set the choice, there is no menu and only first found ext2 partition is used. When I created bootmenu, initfs could boot only from mmcblk0p1 which was not very useful for running cloned system. Later they added search_root_onmmc() which scans all mmc partitions for executable /sbin/init and first one is booted.

Re: *really* backing up an n800?
 

Yes, you can use mkfs.jffs2 also on linux desktop to create the image later. Linux/Mac flasher can write such image of rootfs (or initfs or kernel) separately. Sadly it cannot read it from device. Usage here
http://maemo.org/development/documen...sher_tool.html

Re: *really* backing up an n800?
 

Could be faulty hardware or you may be victim of this http://blog.homac.de/?p=58 a.k.a Power up Drama http://bugs.maemo.org/show_bug.cgi?id=2673

As for installing initfs with bootmenu so there is a way even if you don't want to use mtd-utils on device. Still, even completely erasing initfs partition is not enough to cause symptoms you saw. See also
http://maemo.org/development/documen...e.html#OSLayer
http://maemo.org/development/documen...ure.html#Flash

Re: *really* backing up an n800?
 

fair enough

really? ::looks::
is that the "set default root device" option? what's the syntax for that?

ok, this is the first I've ever heard about this. so if I were able to put an OS on an sd card, I could use the flasher to tell it to boot off it as long as it's p1? (what's the limitation here, that I can't have a fat32 partition for vm on the same card?)

define "later", I'm using what I believe is the first and only non-beta release of OS2008... or do you mean 'later' as in later hardware?

Re: *really* backing up an n800?
 

neat, that looks promising, thanks. anyone have a link to a guide or something on how to use mkfs.jffs2 to make an image out of a folder/rsync?


bah, figures. that would be too easy, eh? :)


yeah, that sounds like it alright. never thought about putting it in the freezer.

Re: *really* backing up an n800?
 

I'd love to see some sample scripts to accomplish this. I want to implement a similar backup system using rsync.

Re: *really* backing up an n800?
 

The cleaver stuff is really just one very long rsync command, e.g.
I actually blogged about it a while back if your interested (I really must finish building my website! :o )

All the scripting is just the checking that commands executed correctly and building up the above command.

I hope that helps.

Re: *really* backing up an n800?
 

Thanks for the info!

Re: *really* backing up an n800?
 

so, I think doing daily rsyncs and compiling them to a flashable image is probably the best overall backup solution. can anyone point me to a reference on how to do this?

also, does anyone have any further information on booting from SD using the stock init.fs as fanoush noted? I'm curious what the limitations are.

Re: *really* backing up an n800?
 

mkfs.jffs2 is the command, see the link in post #3 for usage. Also try to search for 'rootfs' on www.maemo.org
Check README.txt inside initfs_flasher.tgz and then maybe re-read this thread.

Re: *really* backing up an n800?
 

ah ok, thanks. I missed that you had a complete command there with all the endian and cleanmarker parameters and stuff (which is what I was unsure of).

ok, that answers my question as to when they put in the partition searching, but I'm still curious what the limitations are re: first partition (even if it's a moot point now :) ).

I'm probably going to try your init.fs again, but I'm trying to make a couple bootable backups I can test on an SD card first in case something goes wrong again.

Re: *really* backing up an n800?
 

So, did this thread die? Is there no easy way to backup and restore? something for the average user...

Re: *really* backing up an n800?
 

This is a FAQ and should be added to a Wiki when someone provides a clear answer. I don't worry about it myself, and am willing to accept smoke and ashes from my tablet from time to time. Starting over from nothing has its benefits.