Openssl sign csr with san. We will be using openssl command to generate and sign the certificate. key 2048 Generating RSA private key, 2048 bit long modulus This document provides basic steps to creating a CSR (certificate signing request) with multiple SAN (Subject Alternative Name) entries, by using IBM i OpenSSL (Portable Utilities 5733-SC1). crt -CAkey ca. pem 2048 Create a config file (cisco_fw_csr_config. This technology document assumes a valid CSR with Subject Alternative Name (SAN) information already exists. May 8, 2024 · In this article we will learn the steps to create SAN Certificate using openssl generate csr with san command line and openssl sign csr with subject alternative name. These commands was tested on the Mac OS command line using iTerm 2. Here’s how you can generate a CSR and Key File with OpenSSL for a SAN certificate: Apr 7, 2022 · This minimalist post is about creating a private key and a certificate signing request (CSR) for a SAN SSL certificate using OpenSSL. cnf file on your local environment Aug 13, 2025 · To overcome this limitation, the recommended approach is to add SAN values directly into the CSR using tools like OpenSSL. You can use these signed certificates in a variety of situations, such as to secure connections to a web server or to authenticate clients connecting to a service. I read some tutorials on including a SAN with OpenSSL in a one-liner (without a config file created) and normally this should work. Read all about our nonprofit work this year in our 2025 Annual Report. key -CAcreateserial -out. If you’re using Windows you will need to manually import the private key, or create the SAN CSR using their utilities. SAN certificates allow you to secure multiple domains or subdomains with a single certificate. Aug 10, 2020 · In this tutorial we will learn about SAN certificates and steps to generate CSR for SAN certificates. Sep 15, 2023 · Creating a Certificate Signing Request (CSR) and Key File for a Subject Alternative Name (SAN) certificate with OpenSSL involves a few steps. So I have decided to create a dedicated tutorial to explain why CSR is important, and things to consider when writing a CSR. Jul 15, 2024 · I do not get any errors in creation, but neither the CSR nor the certificate have the SAN included. Sign server and client certificates We will be signing certificates using our intermediate CA. csr -CA ca. Apr 12, 2023 · While the common name can be considered cosmetic for Web Server certificates, the SAN is the relevant field for verification. In this article, we see the creation and application of SAN CSR and Certs with openssl Generate CSR with SAN using openssl Generate private key We need to generate private key, which we will using for creating the CSR [root@3-vcp san_test]# openssl genrsa -out SAN_Privatekey. Mar 2, 2022 · How to manually generate a Certificate Signing Request (or CSR) in an Apache or Nginx web hosting environment using OpenSSL. Aug 28, 2021 · I have now covered multiple tutorials on working with openssl certificates. Aug 17, 2025 · Learn how to use openssl generate csr with san to create a certificate with multiple domain names for secure, flexible web hosting. But there is one question where I get a lot of questions where certificate doesn’t work due to incorrect entries in Certificate Signing Request. These commands was tested on the Mac OS command line using Jan 23, 2014 · During my search, I found several ways of signing a SSL Certificate Signing Request: Using the x509 module: openssl x509 -req -days 360 -in server. In this blog post, we will show you how to generate a CSR with Feb 9, 2026 · As per here Know about SAN Certificate and How to Create With OpenSSL, follow the below steps to create, generate and verify the CSR with SAN: Create a san. This ensures that, when the Certificate Authority (CA) signs the CSR, the resulting certificate contains the desired SAN entries. Jun 10, 2020 · For SAN's and EKU's in OpenSSL: Generate the key: openssl genrsa -out key. cnf) according to your needs: [req] distinguished_name = req_distinguished_name req_extensions = v3_req [req_distinguished_name] countryName = Country Name (2 letter code) countryName_default = BE stateOrProvinceName = State or Province Name (full name Jun 9, 2025 · OpenSSL is typically the easiest way to create a certificate signing request (CSR) for an SSL Certificate. Most systems with a command line input should already have OpenSSL, all you need to do is follow these instructions. Apr 7, 2022 · This minimalist post is about creating a private key and a certificate signing request (CSR) for a SAN SSL certificate using OpenSSL. Feb 5, 2026 · Let's Encrypt is a free, automated, and open Certificate Authority brought to you by the nonprofit Internet Security Research Group (ISRG). Dec 11, 2025 · In this guide, we’ll demystify SANs, explain why they’re critical, and walk through step-by-step methods to add SANs to SSL certificates using OpenSSL (for general use cases) and Keytool (for Java-based applications like Tomcat or Jetty). A Certificate Signing Request (CSR) or PKCS#10 is a digital request from an applicant to a Certificate Authority (CA) for signed digital certificate. jts drz hvw oid mus hpm pst hsq juh nia vat ykz edj vlv dvg