WD My Cloud EX2 has an Marvell Armada-370 CPU (
Marvell PJ4Bv7 Processor rev 1 (v7l)) with 512MB RAM.
This device uses 32-bit binaries with
64K page size. WD releases a cross-compilation environment as part of its "WD My Cloud EX2 GPL Source Code". Download it from WD support page (making sure it matches your firmware version) and follow the instructions in
My_Cloud_EX2_Release_Notes_GPL_*.txt to setup the environment. I recommend using a Debian OS.
The following packages are required to use the cross-compilation environment:
build-essential automake lib32z1