Note: if the CSR was generated this way but the certificate needs to be installed on a Windows server (i.e. IIS), you’ll need to generate the PFX file from the certificate and Private key. To do that, use this command: openssl pkcs12 -export -out.your certificate.pfx -inkey server.key -in.your certificate.p7b. Common OpenSSL Commands with Keys and Certificates. Generate RSA private key with certificate in a single command openssl req -x509 -newkey rsa:4096 -sha256 -keyout example.key -out example.crt -subj '/CN=example.com' -days 3650 -passout pass:foobar Generate Certificate Signing Request (CSR) from private key with passphrase. The -key option specifies an existing private key (domain.key) that will be used to generate a new CSR. The -new option indicates that a CSR is being generated. Generate a CSR from an Existing Certificate and Private Key. Use this method if you want to renew an existing certificate but you or your CA do not have the original CSR for some reason. OpenSSL is an open source software library that provides the pkcs12 command for generating PKCS#12 files from a private key and a certificate. The private key and certificate must be in Privacy Enhanced Mail (PEM) format (for example, base64-encoded with -BEGIN CERTIFICATE-and -END CERTIFICATE-headers and footers).

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. However, it also has hundreds of different functions that allow you to view the details of a CSR or certificate, compare an MD5 hash of the certificate and private key (to make sure they match), verify that a certificate is installed properly on any website, and convert the certificate to a different format. A compiled version of OpenSSL for Windows can be found here.

If you don't want to bother with OpenSSL, you can do many of the same things with our SSL Certificate Tools. Below, we have listed the most common OpenSSL commands and their usage:

General OpenSSL Commands

These commands allow you to generate CSRs, Certificates, Private Keys and do other miscellaneous tasks.

• Generate a new private key and Certificate Signing Request
• Generate a self-signed certificate (see How to Create and Install an Apache Self Signed Certificate for more info)
• Generate a certificate signing request (CSR) for an existing private key
• Generate a certificate signing request based on an existing certificate
• Remove a passphrase from a private key

Checking Using OpenSSL

If you need to check the information within a Certificate, CSR or Private Key, use these commands. You can also check CSRs and check certificates using our online tools.

• Check a Certificate Signing Request (CSR)
• Check a private key
• Check a certificate
• Check a PKCS#12 file (.pfx or .p12)

Debugging Using OpenSSL

If you are receiving an error that the private doesn't match the certificate or that a certificate that you installed to a site is not trusted, try one of these commands. If you are trying to verify that an SSL certificate is installed correctly, be sure to check out the SSL Checker.

• Check an MD5 hash of the public key to ensure that it matches with what is in a CSR or private key
• Check an SSL connection. All the certificates (including Intermediates) should be displayed

Converting Using OpenSSL

These commands allow you to convert certificates and keys to different formats to make them compatible with specific types of servers or software. For example, you can convert a normal PEM file that would work with Apache to a PFX (PKCS#12) file and use it with Tomcat or IIS. Use our SSL Converter to convert certificates without messing with OpenSSL.

• Convert a DER file (.crt .cer .der) to PEM
• Convert a PEM file to DER
• Convert a PKCS#12 file (.pfx .p12) containing a private key and certificates to PEM

  You can add -nocerts to only output the private key or add -nokeys to only output the certificates.

• Convert a PEM certificate file and a private key to PKCS#12 (.pfx .p12)

Originally posted on Sun Jan 13, 2008

Generate a certificate signing request

Before you can install a Secure Socket Layer (SSL) certificate, you must first generate a certificate signing request (CSR). You can do this by using one of the following methods:

OpenSSL

The following sections describe how to use OpenSSL to generate a CSR for a single host name. If you want to generate a CSR for multiple host names, we recommend using the Cloud Control Panel or the MyRackspace Portal.

Install OpenSSL

Check whether OpenSSL is installed by using the following command:

• CentOS® and Red Hat® Enterprise Linux®

  The following output provides an example of what the command returns:

• Debian® and the Ubuntu® operating system

  The following output provides an example of what the command returns:

If the preceding packages are not returned, install OpenSSL by running the following command:

• CentOS and Red Hat

• Debian and the Ubuntu operating system

Generate the RSA key

Run the following commands to create a directory in which to store your RSA key, substituting a directory name of your choice:

Run the following command to generate a private key:

Create a CSR

Run the following command to create a CSR with the RSA private key (output is in Privacy-Enhanced Mail (PEM) format):

When prompted, enter the necessary information for creating a CSR by using the conventions shown in the following table.

Note: You cannot use the following characters in the Organization Name or Organizational Unit fields: < > ~ ! @ # $ % ^ * / ( ) ? . , &

Openssl Create Certificate With Existing Private Key

Warning: Leave the challenge password blank (press Enter).

Verify your CSR

Run the following command to verify your CSR:

After you have verified your CSR, you can submit it to a CA to purchase an SSL certificate.

Windows IIS Manager

Use the following steps to generate a CSR by using Windows IIS Manager:

Note: The following steps are for IIS 8 or IIS 8.5 on Windows Server 2012.

1. Open IIS Manager.
2. In the left-hand Connections pane, click the server for which you want to generate a CSR.
3. In the center server Home pane under the IIS section, double-click Server Certificates.
4. In the right-hand Actions pane, click Create Certificate Request.

5. In the Request Certificate wizard, on the Distinguished Name Properties page, enter the following information and then click Next.

   Field	Explanation	Example
   Common Name	The fully qualified domain name to which the certificate applies. The domain names example.com and www.example.com are distinct from each other, so be sure to submit your request for the right domain. If you are purchasing a wildcard certificate, use *.example.com.	example.com
   Organization Name	The exact legal name of your organization. The CA might seek to confirm that your organization is real and legally registered, so don’t abbreviate words that aren’t abbreviated in the organization’s legal name.	Example Inc.
   Organizational Unit	The branch of your organization that is making the request.	Marketing
   City/locality	The city where your organization is legally located. Do not abbreviate the city name.	San Antonio
   State/province	The state or province where your organization is legally located. Do not abbreviate the state or province name.	Texas
   Country/region	The two-letter ISO abbreviation for your country.	US

6. On the Cryptographic Server Provider Properties page, enter the following information and then click Next.

   • Cryptographic service provider: Unless you have a specific cryptographic provider, use the default selection.
   • Bit length: 2048 is the recommended bit length.
7. On the File Name page, enter the location where you want to save the certificate request file and then click Finish.

After you have generated the CSR, you can submit it to a CA to purchase an SSL certificate.

Cloud Control Panel

Rackspace provides the CSR Generator for generating a CSR. The CSR Generator shows you the CSRs that you currently have and lets you create new CSRs with a simple form. After you have entered your details, the generator combines them with your private key so that you can submit the combined encoded information to a CA.

When you are done with the generator, you can return to the Cloud Control Panel by clicking any of the links in the top navigation or by going to login.rackspace.com and selecting Rackspace Cloud from the drop-down product menu in the top navigation bar.

Access the CSR Generator

Access the CSR Generator directly or through the Control Panel by using the following steps:

1. Log in to the Cloud Control Panel and select Rackspace Cloud from the drop-down product menu in the top navigation bar.
2. In the top navigation bar, click Servers > Cloud Servers.
3. Click the name of the server for which you want to generate a CSR.
4. In the right-hand Managing Your Server section under Help me with, click Generate a CSR.

The generator lists your existing CSRs, if you have any, organized by domain name.

Generate a CSR

1. Click Create CSR.

2. Enter the following information, which will be associated with the CSR:

   Field	Explanation	Example
   Domain Name	The fully qualified domain name to which the certificate applies. The domain names example.com and www.example.com are distinct from each other, so be sure to submit your request for the right domain. If you want to secure both domains, you can use the Alt Names field. If you are purchasing a wildcard certificate, use *.example.com.	example.com
   Alt Names	(Optional) Additional domains that you want to add to the request. Each CA treats these differently, and the CA might charge for additional names. You can submit a comma-separated list.	www.example.com, secure.example.com
   Email Address	(Optional) A contact email address for the certificate.	support@example.com
   Organization Name	The exact legal name of your organization. The CA might seek to confirm that your organization is real and legally registered, so don’t abbreviate words that aren’t abbreviated in the organization’s legal name.	Example Inc.
   Organizational Unit	(Optional) The branch of your organization that is making the request.	Marketing
   City	The city where your organization is legally located. Do not abbreviate the city name.	San Antonio
   State or Province	The state or province where your organization is legally located. Do not abbreviate the state or province name.	Texas
   Country	Choose your country from the drop-down menu. The two-letter ISO abbreviation for your country is included in the CSR.	United States
   Private Key Bit Length	Key sizes smaller than 2048 are considered insecure and might not be accepted by a CA.	1024,2048,4096
   Hashing Algorithm	Both algorithms are currently trusted in mainstream browsers and offer industry recommended security. SHA-512 requires additional CPU processing.	SHA-256, SHA-512

   Note: You cannot use the following characters in the Organization Name or Organizational Unit fields: < > ~ ! @ # $ % ^ * / ( ) ? . , &

3. After you have entered all the required information, click Create CSR.

It can take between 5 and 60 seconds for the CSR to be generated. You might need to refresh the page that displays your CSRs before the new CSR is listed.

View CSR details

When CSR has been generated, you can click its UUID (unique identifier) in the CSR list to view its details screen.

This screen displays the information that you provided, the text of the CSR, and its associated private key.

Submit the CSR to the CA

The text in the Certificate Request field is the CSR. It contains encoded details of the CSR and your public key.

To request your SSL certificate, copy the Certificate Request text and submit it to your CA. Include all the text, including the BEGIN and END lines at the beginning and end of the text block.

Install the private key

Copy the private key to the server that will host the certificate. See your application documentation to determine where to install the private key and certificate on your server.

MyRackspace Portal

If you are a Managed or Dedicated customer, you can request a CSR through the MyRackspace Portal by using the following steps:

1. Log in to the MyRackspace Portal and select Dedicated Hosting from the drop-down product menu in the top navigation bar.
2. In the top navigation bar, click Tickets > Create Ticket.
3. On the Tickets / Create New Ticket page, select Generate Certificate Signing Request (CSR) from the Subject drop-down list.

4. Enter the following information in the Ticket Details section:

   Field	Explanation	Example
   Device(s)	The server or servers for which you want to generate a CSR. Use the drop-down menu to select your servers.
   Common Name	The fully qualified domain name to which the certificate applies. The domain names example.com and www.example.com are distinct from each other, so be sure to submit your request for the right domain. If you want to secure both domains, you can use the Alt Names field. If you are purchasing a wildcard certificate, use *.example.com.	example.com
   Alt. Names	(Optional) Additional domains that you want to add to the request. Each CA treats these differently, and the CA might charge for additional names. You can submit a comma-separated list.	www.example.com, secure.example.com
   Email Address	(Optional) A contact email address for the certificate.	support@example.com
   Organization	The exact legal name of your organization. The CA might seek to confirm that your organization is real and legally registered, so don’t abbreviate words that aren’t abbreviated in the organization’s legal name.	Example Inc.
   Organizational Unit	(Optional) The branch of your organization that is making the request.	Marketing
   Locality (City)	The city where your organization is legally located. Do not abbreviate the city name.	San Antonio
   State or Province Name	The state or province where your organization is legally located. Do not abbreviate the state or province name.	Texas
   Country	Choose your country from the drop-down menu. The two-letter ISO abbreviation for your country is included in the CSR.	United States

   Note: The bit length is automatically set to 2048.

5. Click Create Ticket.

Next steps

Reference

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