Restore factory firmware ZBT Z8102 AX

Installing and Using OpenWrt
1

I just purchased a router ZBT Z8102 AX, with modem RM520N-EU, 8GB eMMC, 1GB Ram.
Before installing openwrt from https://firmware-selector.openwrt.org/?version=SNAPSHOT&target=mediatek%2Ffilogic&id=zbtlink_zbt-z8102ax, how can I back-up original firmware, all the partitions, bootloader, etc.?
There are also modem calibration setup to save?

2

https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=c8c2f522625c8d9eb5acad317e3de7a6b156decf the 1st part, about the 3rd party fw.

Otherwise boot an initramfs, and do it from there, if the boot loader permits it.

3

I'll rephrase what @frollic has referred to:

If your router comes with OpenWrt preinstalled [...] navigate to System -> Backup/Flash firmware,

then see if you have an option to save the mtdblock(s).

If the vendor has removed this option from their firmware, see if you can do the same from the console. One of several related discussions is here.

The modem calibration is stored on the modem itself, you don't need to backup it.

1 Like
4

thanks, I did read the posts, but is not clear to me:
if the firmware is a customized OpenWrt version (customized from the vendor) and I can save mtdblock(s), is enought to revert back to original status? Or I need special packages to write the mtdblock(s) back on router?
thanks
-g

5

You only need a special Openwrt package to write them back.

6

I suppose is this one:

If those files are te correct size then no... Just note that most partitions are read-only and to restore them you need to install mtd-rw then load it modprobe mtd-rw i_want_a_brick=1 and only then will writing work.

7

That's the one.

8

I've received the binary file to full install the original firmware from the vendor. I havn't check the license yet and I'm not sure it's legal. If anyone is interested I can share somewhere here. Just let me know.