In my previous posts: New-OpsMgrRequest and Install-OpsMgrCertificate I posted two nice scripts. However there is a little bug that operating system version is not recognized correctly. Also these scripts have limited Windows versions support — only Windows Vista and higher. Now I have updated both scripts by fixing several bugs and added Windows XP/Windows Server 2003 (including R2) support. The following scripts demonstrates as well as CertEnroll and XEnroll CryptoAPI interfaces and how you can deal with them in Windows PowerShell. Here is an updated code:

This article will explain and demonstrate the techniques that will add custom extensions to certificate requests.

A little abstract. As you know, when Hewlett-Packard iLO generate certificate request for SSL it include server *short* name to the Subject field. There is no way to change subject name format. While output request file is signed you cannot edit this request, because signature will become broken and CA (Certification Authority) will reject this request. Subject name short format is not quite useful, because many administrators prefer FQDN (Fully Qualified Domain Name), for example: iLO1.domain.com. I agree with this point that FQDN are more useful and can be used in various network configurations and in multi-domain/multi-forest environments.

Disclaimer: this article contains information about modifying the IIS configuration files. Before you modify the IIS configuration file, make sure to back it up and make sure that you understand how to restore the file if a problem occurs.

This article contains information about unsupported operations. Before you modify any settings described below, make sure to backup your system and make sure that you understand how to restore the system if a problem occurs

A little abstract. The Online Certificate Status Protocol (OCSP) is an Internet protocol used for obtaining the revocation status of an X.509 digital certificate. Why it has been developed? Prior to OCSP, clients checks certificate status (valid/revoked) using certificate revocation lists (CRLs). Client software downloads certificate issuer CRL file and examines its Revocation List property. If particular certificate serial number is present in CRL, certificate is considered as revoked or invalid and is rejected for usage. While CRLs may contain many revoked certificates, CRL size is grown. Typically empty CRL with default settings is about 600 bytes (the CRL size generally depends on field and extension textual information length and signing certificate key length). Each revoked certificate entry is about 80 bytes. If 10 certificates are revoked, CRL size will be: 600 + 80 * 10 = 1400 bytes. For 100 revoked certificates the size will be about 9 kilobytes. For 100 000 revoked certificates, the size will be approximately 8 megabytes.

Continuing my previous post I want to discuss about certificate installation. As you know, certificate erollment generally consist of several steps:

• Certificate Request generation;
• Certificate Request submission to Certification Authority;
• Certificate Request response (certificate signed by CA) installation;

In previous post I have demonstrated how certificate request can be created using native PowerShell capabilities. While CA server cannot be contacted directly from managed client, you will have to manually transfer and submit certificate to Certification Authority.

When you create Certificate Request, it is placed in Certificate Enrollment Requests container (in Certificates snap-in). This request waits for signed certificate public part. When certificate public part is signed by external authority, signed certificate must be installed to local store. Installation process consist of two steps:

I would like to demonstrate a quite pretty script that simplifies certificate request generation for OpsMgr managed clients. Recently we had have to use various complex (for administrators that are not familiar with digital certificates) methods, such:

• CertReq.exe utility in conjunction with Policy.inf file (as decribed here: Certificate Enrollment for System Center Operations Manager Agent);
• Request generation using MMC console Certificates snap-in.

Both methods require some additional steps to generate request. For example, if you use CertReq.exe utility you need to write enough complex certificate enrollment configuration file. If you use Certificates snap-in you will need to manually specify all necesary data (such subject, private key settings, certificate extensions, etc). This PowerShell script will do all stuff, so you will have to copy and paste script to PowerShell console and run it.