Deciding on Key Generation Options

One of the most versatile SSL tools is OpenSSL which is an open source implementation of the SSL protocol. There are versions of OpenSSL for nearly every platform, including Windows, Linux, and Mac OS X. OpenSSL is commonly used to create the CSR and private key for many different platforms, including Apache.

Oct 25, 2019  Generate RSA private key (2048 bit) and a Certificate Signing Request (CSR) with a single command openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out server.csr Convert private key to PEM format openssl rsa -in server.key -outform PEM -out server.pem. Feb 12, 2015  To create a CSR, you need the OpenSSL command line utility installed on your system, otherwise, run the following command to install it. Then issue the following command to generate a CSR and the key that will protect your certificate. $ openssl req -new -newkey rsa:2048 -nodes -keyout example.com.key -out example.com.csr. Openssl genrsa -out./yourkeyfile.key 2048 and then use the file to create a CSR with. Openssl req -new -sha256 -key yourkeyfile.key -out yourcsrfile.csr If you use the one line command the keyfile is created in DER format. Openssl req -new -sha256 -newkey rsa:2048 -nodes -keyout yourkeyfile.key -out yourcsrfile.csr. Both examples show how to create CSR using OpenSSL non-interactively (without being prompted for subject), so you can use them in any shell scripts. Create CSR and Key Without Prompt using OpenSSL. Use the following command to create a new private key 2048 bits in size example.key and generate CSR example.csr from it.

When generating a key, you have to decide three things: the key algorithm, the key size, and whether to use a passphrase.

Key Algorithm

For the key algorithm, you need to take into account its compatibility. For this reason, we recommend you use RSA. However, if you have a specific need to use another algorithm (such as ECDSA), you can use that too, but be aware of the compatibility issues you might run into.

Openssl Command To Generate Private Key And Csr Number

Note: This guide only covers generating keys using the RSA algorithm.

Key Size

For the key size, you need to select a bit length of at least 2048 when using RSA and 256 when using ECDSA; these are the smallest key sizes allowed for SSL certificates. Unless you need to use a larger key size, we recommend sticking with 2048 with RSA and 256 with ECDSA.

Note: In older versions of OpenSSL, if no key size is specified, the default key size of 512 is used. Any key size lower than 2048 is considered unsecure and should never be used.

Passphrase

Openssl Windows Create Csr

For the passphrase, you need to decide whether you want to use one. If used, the private key will be encrypted using the specified encryption method, and it will be impossible to use without the passphrase. Because there are pros and cons with both options, it's important you understand the implications of using or not using a passphrase. In this guide, we will not be using a passphrase in our examples.