iRule v9 to v10 conversion

What I think the problem was is that, at run-time, SSL::sessionid returned null. If SSL::sessionid returns null, when the "session add" command runs, the argument is missing.

 

 

It's possible for SSL::sessionid to return null - but only in v10. In v9, instead of returning null, it would return a string of 64 zeros. See:

 

http://devcentral.f5.com/wiki/default.aspx/iRules/SSL__sessionid.html -- so this explains why you only ran into the problem after upgrading.

 

 

The reason it began working after your change is because you concatenated it with the client certificate -- so now it will never be null.

 

 

The better approach might be to test that SSL::sessionid returned a real value before attempting to use it in the session command.