How to install Docker on an unsupported Synology NAS (updated 2020)

Synology has limited Docker availability in the package manager to only some select models (models and links updated 12/21/2020) 21 series:DS1821+, DS1621xs+, DS1621+, DVA3221 20 series:FS6400, FS3600, FS3400, RS820RP+, RS820+, DS920+, DS720+, DS620slim, DS420+, DS220+, DS1520+, SA3600, SA3400, SA3200D 19 series:RS1619xs+, RS1219+, DS2419+, DS1819+, DS1019+, DVA3219 18 series:FS1018, RS3618xs, RS818RP+, Read more…