RouterOS (sometimes shortened to ROS) is an embedded operating system used on various appliances from Mikrotik. Depending on the version of RouterOS, not all commands may be available, and if major differences are known, they are combined in a version-specific section.
SSH into an appliance or virtual machine running RouterOS, or in case of a physical device use a local serial connection in order to apply these options.
RouterOS >= 7.7
RouterOS 7.7 was the first release supporting ed25519 host keys.
/ip ssh set host-key-size=4096 host-key-type=ed25519 strong-crypto=yes
/ip/ssh/regenerate-host-key