PKCS8 from Private Key

How to convert PKCS8 from Private Key

openssl pkcs8 -topk8 -nocrypt -in `hostname -s`.key -out `hostname -s`.pkcs8
mv `hostname -s`.pkcs8 `hostname -s`.key

How to verify:
openssl rsa -noout -modules -in `hostname -s`.key | openssl md5
openssl x509 -noout -modules -in `hostname -s`.crt | openssl md5