So my N9 is going in for repairs, and I'm pretty confident they're (Nokia Service) just going to replace it.

Best outcome:
I power up my new phone, and I cannot tel it's a new phone.

I've modified a few files in /etc in the pursuit of the best audio quality, custom themes, custom boot, tons of photos, and music.

So, how can I make a carbon copy of my current mobile?

For high-level backups: Use the built-in Backup utility, and then connect the N9 via USB Mass Storage mode and copy everything over (that will include photos and music, make sure to show hidden files, because the backups are stored in ".backups" in MyDocs).

For lower-level backups: Use rsync from Maemo 5 (the package installs fine on Harmattan) via SSH to copy files over. Not sure if Aegis would get in your way.

If you don't mind open mode then Backup Menu is a nice utility too

Yes, I am fairly sure that if you are not in open mode aegis does hinder the things
Anyway backing up everything just in case (and selectively restoring the needed bits on teh new device) is the safest bet.

Yeah, permanently in open mode ATM.

@juice
How does one selectively restore things?

@thp
rsync, do you have any idea how long it would take to do a complete backup?
And will the low-level backup cover the high level too, or would I need to use rsync AND the backup utility?

And a general question:
Is it possible for me to transfer my accounts betwixt phones, or will I have to recreate the accounts first?

By selectively restoring, I mean you could just copy back not all but some of the things backed up. Propably not relevant in your case as you want to have the device to be exactly identical to how the previous device was.

Best way to achieve this IMHO is to copy the content of mmcblk0p2 (root partition), mmcblk0p3 (home partition) and mmcblk0p1 (MyDocs partition) with "tar -cvf" for example.

To backup the whole N9 I use the following technique (linux/mac with terminal):

1) Plug your N9 to your computer
2) Put it in SDK mode (while already in dev mode of course)
3) Open SDK Connectivity App and look at the IP address and generated Password
4) Enter the following command in term on the **computer** :

Where 192.168.2.15 is the n9 IP. Then you'll have to enter the generated password and let the process happen.

To restore the backup, use this command instead (with same process) :

Never tried the restore function, but theorically it should do the trick. If someone want to improve those commands, he is welcome. For instance I'm not sure that the "exclude" commands are taken into account since I read that "tar" needs an "x" for that, but I didn't know where to put it.

Anyway, that how I do it and it works for me

EDIT: As it turns out Tar and GNU Tar are not working the same way. So the command line shown above is right (or so it seems) but on mac os (not-GNU Tar) for instance you'll have to put the source path (in this case "/") **before** the --exclude functions, right after the "-", or the excluded paths will not be taken into account.