Cisco PRSM – Replace the Certificate Using Microsoft Certificate Services

KB ID 0001023 


Cisco PRSM gives you the ability to import certificates into it, but like other Linux distros does not give you the tools to generate the actual certificate request. The documentation tells you to use OpenSSL to this. I was just about to fire up a CentOS box when I remembered I did something similar for VMware 5.5 not so long ago, would the same procedure work here? Yes it did, and it’s a lot easier than growing a ginger ponytail, donning sandals and firing up Linux.


The following procedure was carried out on Windows Server 2012 R2. I want my certificate to have a common name of (change your configs and commands accordingly).

1. Download and install the following.

Microsoft Visual C++ 2008 Redistributable Package (x86) and Shining Light Productions installer for OpenSSL x86 version 0.98r (or later)

2. Accept all the defaults and it should install to C:OpenSSL-Win32 go there, and in the bin directory make a backup of the openssl.cfg file.

Backup OpenSSL

2. Open the original openssl.cfg file and delete everything out of it, then paste in the following text, replace the values in red with your own, and save the file.

[ req ]
default_bits = 2048
default_keyfile =
distinguished_name = req_distinguished_name
encrypt_key = no
prompt = no
string_mask = nombstr
req_extensions = v3_req

[ v3_req ]
basicConstraints = CA:FALSE
keyUsage = digitalSignature, keyEncipherment, dataEncipherment
extendedKeyUsage = serverAuth, clientAuth
subjectAltName = DNS:PRSM, IP:,

[ req_distinguished_name ]
countryName = GB
stateOrProvinceName = Teesside
localityName = Middlesbrough
0.organizationName = PeteNetLive
organizationalUnitName = Technical Services
commonName =

3. Open an administrative command window, issue the following three commands;

cd C:OpenSSL-Win32Bin

openssl req -new -nodes -out -keyout -config openssl.cfg

openssl rsa -in -out

PRSM Generate CSR

Don’t worry if it says it cant read the openssl.cnf file

4. If you look in C:OpenSSL-Win32bin directory you will see the CSR (certificate request) has been generated.

PRSM csr certificate

5. Open the .csr file with notepad and copy all the text, (this is a request in PEM format). This is what you will give to your CA to request the certificate, copy that to the clipboard.

PRSM PEM Certificate

6. Connect to your Certificate Authority web enrollment portal > Request a certificate.

PRSM Microsoft Certificate

7. Advanced certificate request.

Advanced Cert Request

8. Submit a certificate request by using a base-64-encoded CMC or PKCS #10 file, or submit a renewal request by using a base-64-encoded PKCS #7 file.

PRSM Certificate Request

9. Paste in the PEM text you copied to the clipboard > Set the certificate template to ‘Web Server’ > Submit.

Note: Your CA may have a different template for web server certificates, if so use that one. If you don’t see web server either it’s not been published, or your user does not have rights to the certificate template.

PRSM Web Cert

10. Choose ‘Base 64 encoded’ > Download > Save the cert in the directory you were using earlier (you will see why in a minute) > I give it the same name as the common name on the certificate so I saved it as

PRSM Base 64 encoded

11. Here it is, but there is still a problem with it, PRSM needs the certificate in x509 format, (it isn’t). But OpenSSL-Win32 can convert it for us.

Cisco PRIME Certificate

How to Convert a Windows .cer file to an x509 .crt file

12. Open and administrative command window and issue the following two commands;

cd C:OpenSSL-Win32bin
openssl x509 -in -out

Convert cer to crt

13. Now it looks better, for PRSM we need this file AND we need the .key file, (not the one that ends in xxx-orig.key!) In the example below I’ve kept everything neat so the other file i need is, (third one down).

Convert certificate to x509

14. Connect to PRSM > Administration > Server Certificates > Browse and select both files.

PRSM - Certificates

15. Install and Restart Server.

PRSM - Certificates from Microsoft Certificate Services

16. Restart.

PRSM - Certificates from Microsoft Certificate Services

17. Refresh your web session and you should now be using the correct certificate.

PRSM - Certificates from Microsoft Certificate Services

Related Articles, References, Credits, or External Links


Author: Migrated

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