Saving shibd session state during restarts

[Lenny Miceli]

Is it possible to somehow save session state to a file or somewhere else 
when you want to restart shibd?

We're running v2.5.3 and use a shared shibd process so our web servers 
can be load balanced and we don't have to worry about LB sticky.  This 
configuration works very well for us other than when we want to restart 
shibd.  After a restart the apache server comes back with error messages 
like:

[Wed Jun 11 09:02:30 2014] [error] [client 128.205.194.165] Failure 
receiving response to remoted message (default/Login::run::SAML2SI).
or
[Wed Jun 11 09:28:18 2014] [error] [client 128.205.194.165] Failure 
receiving response to remoted message (find::StorageService::SessionCache).

These errors makes sense since the session state has been lost since 
shibd was restarted.

Reading the documentation you can have a shared DB that should solve 
this problem but there are a lot of caveats per the doc so we don't want 
to have to go there.

It would be ideal if you can give an option to shibd on shutdown to 
store the session info then on startup give it an option to read that 
stored session info.

Thanks,
   Lenny