Freitag, 14. November 2014
complete Backup of N900
mikeace, 15:02h
The N900 has several storages. Each has to be saved in order to backup everything.
A good program to do that is the Backup Manager which does backup rootfs and optfs. It runs directly from the bootloader so the system to be backed up is not running.
unfortunately it doesn't back up everything. Contacts and installed programs are all there but it misses to backup the MyDocs directory!
So what is Backed up and what not again?
Let's excurse inte the different partitions which exist on a N900.
Backup Manager saves "rootfs" and "optfs". That corresponds to the rootfs device and /dev/mmcblk0p2 from the eMMC flash:
So the big 28 GB partition with userdata (/dev/mmcblk0p1) is NOT saved.
You have to back it up separately:
And there it went ... down the drain .. all my user data was lost. ;(
that's btw the reason i'm writing this article here. ;)
Interesingly enough - this didn't work for me 100% as I have installed the kernel-power which was not restored by restoring optfs.
The kernel image is in /boot/zImage-2.6.28.10-power52 -> /opt/boot/zImage-2.6.28.10-power52 which is on /opt which is mounted from /home/opt which is backed up in the optfs tarball from Backup Manager.
I don't see, why my (supposedly backed up) kernel-power did not get restored. Instead the normal vanilla kernel was running after a complete restore.
Probably the kernel is running during backup/restore and can't be overwritten?
Next time i'm flashing I'll have to check this.
A good program to do that is the Backup Manager which does backup rootfs and optfs. It runs directly from the bootloader so the system to be backed up is not running.
unfortunately it doesn't back up everything. Contacts and installed programs are all there but it misses to backup the MyDocs directory!
So what is Backed up and what not again?
Let's excurse inte the different partitions which exist on a N900.
Device Size Type FS Mountpoint Description
/dev/mmcblk0: 32 GB internal eMMC flash on the N900.
/dev/mmcblk0p1: 28 GB 0c FAT32 (LBA) vfat /home/user/MyDocs 27 GiB VFAT MyDocs partition. Exposed when the N900 is connected to a PC in mass storage mode .
/dev/mmcblk0p2: 2 GB 83 Linux ext3 /home This also contains the /opt folder (mounted on /home/opt) where optified apps are stored.
/dev/mmcblk0p3: 768 MB 82 Linux Swap swap
Backup Manager saves "rootfs" and "optfs". That corresponds to the rootfs device and /dev/mmcblk0p2 from the eMMC flash:
$ mount
rootfs on / type rootfs (rw)
/dev/mmcblk0p2 on /home type ext3 (rw, noatime, ....)
So the big 28 GB partition with userdata (/dev/mmcblk0p1) is NOT saved.
You have to back it up separately:
$ cd /home/user/MyDocs
$ tar -cf /media/mmc1/home_user_MyDocs.tar .
And there it went ... down the drain .. all my user data was lost. ;(
that's btw the reason i'm writing this article here. ;)
Interesingly enough - this didn't work for me 100% as I have installed the kernel-power which was not restored by restoring optfs.
The kernel image is in /boot/zImage-2.6.28.10-power52 -> /opt/boot/zImage-2.6.28.10-power52 which is on /opt which is mounted from /home/opt which is backed up in the optfs tarball from Backup Manager.
I don't see, why my (supposedly backed up) kernel-power did not get restored. Instead the normal vanilla kernel was running after a complete restore.
Probably the kernel is running during backup/restore and can't be overwritten?
Next time i'm flashing I'll have to check this.
... comment
