Multiple kernels on one machine?

[Ewald Jenisch]

Hi,

I'm currently in the process of upgrading my kernel (5.1). Afaik, every 
time one installs a new kernel with "make installkernel" the old 
/boot/kernel is moved to /boot/kernel.old thus overwriting the old 
/boot/kernel.old.

In order to keep a working kernel: Is it possible to *keep* an old 
kernel by copying, say /boot/kernel.old to e.g. /boot/mykernel and then 
via the boot-menu starting this kernel by

unload
boot mykernel

??

If yes, can I simply copy (e.g. via tar | tar xpf..) the old kernel 
directory to a new name or is there anything else I should consider?

TIA for your help
-ewald