Firmware

General_VTO3211D_Eng_P_32M_V3.200.10J7000.0.R.20180306.bin.bin

Rhino firmware released Mar 6, 2018. May work with 1 device, including VTO3221D.

Download

Permanent copy on the Internet Archive (item page)

Hardware IDs this firmware's installer accepts (1 device).

Where these IDs come from

hwid: the device's own hardware check list, 1 ID
Install: the installer's device list (board families), 5 IDs, vendor General_OC (not counted: a more specific list exists)
check.img: the device's own hardware check list, 1 ID

Read from inside the firmware (dahua package (zip variant)).

Flash layout: 14 partitions, 9 written by this firmware

From the firmware's partition table (partitionV2.txt).

Partition	Start	End	Size	Image	Filesystem	Built
U-Boot	0x200000	0x300000	1.0 MB	dhboot.bin.img	—	2018-03-06
hwid	0x300000	0x400000	1.0 MB	not written	—	—
updateflag	0x400000	0x500000	1.0 MB	not written	—	—
partition(ro)	0x500000	0x600000	1.0 MB	partition-x.cramfs.img	cramfs	2018-03-06
custom(ro)	0x600000	0x980000	3.5 MB	custom-x.squashfs.img	squashfs	2018-03-06
product(ro)	0x980000	0xd00000	3.5 MB	pd-x.squashfs.img	squashfs	2018-03-06
Kernel	0xd00000	0x1200000	5.0 MB	kernel.img	—	2018-03-06
romfs(ro)	0x1200000	0x1a00000	8.0 MB	romfs-x.squashfs.img	squashfs	2018-03-06
web(ro)	0x1a00000	0x1e00000	4.0 MB	web-x.squashfs.img	squashfs	2018-03-06
data(ro)	0x1e00000	0x2200000	4.0 MB	data-x.squashfs.img	cramfs	2018-03-06
user(ro)	0x2200000	0x3b80000	25.5 MB	user-x.squashfs.img	squashfs	2018-03-06
syslog	0x7200000	0x7600000	4.0 MB	not written	ubi	—
config	0x7600000	0x7a00000	4.0 MB	not written	ubi	—
backup	0x7a00000	0x7e00000	4.0 MB	not written	ubi	—

Other files for much of the same hardware, from any vendor.