openssl genrsa -aes256 -out ./example.org.key 4096

openssl genrsa -aes256 -out ./example.org.key 4096
Generating RSA private key, 4096 bit long modulus
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e is 65537 (0x10001)
Enter pass phrase for ./example.org.key:
Verifying - Enter pass phrase for ./example.org.key:

See also

• openssl rsa, openssl genrsa