session add ssl [SSL::sessionid]

My question is in regard to SSL::sessionid.

 

 

In the definition below (1) it is stated:

 

 

"Returns the current connection's SSL session ID if it exists in the session cache. If it does not exist in the cache, returns a string of 64 zeroes."

 

 

I am trying to use SSL::sessionid in an iRule modelled on (2) below. I am using SSL::sessionid as the key on a session (session add ssl [SSL::sessionid] $ssl_stuff $session_timeout). The trouble is, every entry in the session table has a key (aka SSL:sessionid) of 64 0's.

 

 

When does an SSL sessionid get added to the session cache, and where/what is the session cache?

 

 

Where can we find more detail on subjects such as the session cache, for example I'd really like to know more about 'session' and it's modes but do not see anything in the Wiki nor in askF5, is there a specification we can refer to ?

 

 

Regards J

 

(1) http://devcentral.f5.com/wiki/default.aspx/iRules/SSL__sessionid.html

 

(2) http://devcentral.f5.com/wiki/default.aspx/iRules/InsertCertInServerHeaders.html