Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

OpenSSL - Solaris - Windows

When I run c_rehash (OpenSSL 0.9.x in Solaris) and c_rehash (OpenSSL 1.1.x in Windows), the same exact cert.pem file gets converted to a .0 file with a completely different filename.

(Windows) cert.pem => 4e12356.0

(Solaris) cert.pem => 3e121e8.0

Why is this? Shouldn't the hash be the exact same regardless of which version of OpenSSL I'm using?

share|improve this question
up vote 8 down vote accepted

The hash used for these names changed when moving to OpenSSL 1.0. You can revert to the old behaviour using -subject_hash_old. See the documentation:


synonym for ``-subject_hash'' for backward compatibility reasons.


outputs the ``hash'' of the certificate subject name using the older algorithm as used by OpenSSL versions before 1.0.0.

There's more background information in this message. Essentially, the hash algorithm changed from MD5 to SHA-1.

share|improve this answer
Brilliant. Thank you! – Mike B Jun 21 '12 at 22:48

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.