Backing up the 'factory' installed software on NSA325v2

Frik

I'm messing around with my NSA325v2, trying to install different packages and software. I will probably reinstall the complete operating system, but for the time being I'm just experimenting a bit and getting to know the system. As far as I can see, the NAS came preinstalled with a "Busybox" Linux distribution (not sure if one can call it that), logging in with SSH gives me that. Anyway, I was wondering how I could backup this factory installed operating system including all the preinstalled software like the web interface to a USB stick, so that I could restore the system if something goes wrong? Also I would have to enable it to boot up again from the backup etc. How could I go about doing this? Any tips / info appreciated....

Sapphire23

You can make configuration backup in control panel and restore back later on

Mijzelf

It's almost impossible to damage the installed OS by accident. You'll have to write to flashrom for that.

The rootfs you see is a ramdisk, which is embedded in the kernel. So any change you make will be reverted on boot.

The /usr/ directory is basically a loopmounted read-only file, which is located on the first partition. (/dev/sda1). On boot the md5sum of this file is compared to a checksum stored in flash. If it doesn't fit, the file is exchanged by one stored in flash. So any change will be reverted on boot.

The backup you are looking for is basically a firmware upgrade file. That contains the kernel with build-in ramfs, and the /usr/ file.

More info about how the system boots and the file tree is build up can be found in the bootscript /etc/init.d/rcS.

I will probably reinstall the complete operating system,

The NAS is an embedded Linux system, running on an ancient Arm CPU. You can't simply put in an USB stick and install something else. Yet there are a few distro's made available for the NSA325:

OpenWrt, Debian and Arch. Maybe more, but I'm not aware of that.

Frik

@Sapphire23, thanks for the suggestion, I've backed up my current configuration settings just in case. @Mijzelf, thanks for the explanation. What I don't understand then, is what happens when I install for example zy-pkgs. For example, I installed the Entware-ng package, I want to see if I can get some Perl packages installed on the NAS. Where are these things installed then? When I reboot, these are surely not erased again? Sorry if this is a really basic question, but I have to start somewhere I guess.

Mijzelf

Entware-ng is installed on a data volume, and the start script creates a symlink /opt which points to the install directory.

There is a script on the ramdisk, /etc/init.d/zypkg_manager.sh, or something like that, which scans the data volumes on certain places for package start scripts, and execute them on boot.

If you install perl, (or whatever) normally the firmware won't use it, as it is not in it's read-only bubble. Only software which searches the /opt directory (because it's in their PATH) will find&use it.