Source: https://github.com/gnab/rtl8812au
Realtek 802.11ac v4.2.2 (RTL8812AU/RTL8821AU) driver for Armbian builds (tested with linux kernel 3.4.113 on NanoPi NEO & Orange Pi Zero)
Install linux headers and toolchain utilities, if you haven't already. (Note: linux-headers-sun8i is specific to the tested kernel -- yours could be different)
apt-get install linux-headers-sun8i binutils-arm-none-eabi gcc-arm-none-eabi
Clone the repository, then:
cd arm-rtl8812au/
Run the following (with root permissions):
make
make install
Load the driver (Note: use 8812au or 8821au, depending on your adapter's chipset):
modprobe 8812au
To make sure the module loads on boot, append the inserted module name (i.e. 8812au) to /etc/modules