[ 
http://issues.apache.org/jira/browse/DERBY-1326?page=comments#action_12434306 ] 
            
Francois Orsini commented on DERBY-1326:
----------------------------------------

Well, we do connect to the Derby engine instance from the network server layer 
so if the embedded Derby engine goes down, we would have to reinstantiate the 
database connections (logic is not there right now if am not mistaken), which 
means some state(s) have to be kept around and some logic has to be added. But 
then, how do you handle incoming request from the client(s), especially if it 
takes some time to recover the database(s)...What is there is a corruption and 
some database cannot be recovered? What if after a reboot of the engine some 
derby properties have affected the behavior and configuration of the recovered 
databases - For instance, some database properties are static, so they won't be 
taken into account until the next reboot, which can also mean that a client 
(user) would no longer be allowed to authenticate if the authentication 
provider was changed before the next reboot - This is true for Strong Password 
Substitute which only works with BUILT-IN or NONE authentication providers 
right now...Hence in this last case, a security mechanism negotiation needs to 
happen between the client and the network server...Another case if that if you 
enable authentication at the engine level but derby instance has not rebooted 
yet, you will then not be able to re-authenticate based on the cached database 
info per DRDA session - Simply because a password may not be cached at all 
since there was no authentication required beforehand and now there is because 
the static property got picked-up by the database in question at the next 
engine/database reboot...The connection with the database would not work and 
the client would probably get confused with some authentication exception where 
he/she was already authenticated before the Derby engine got shutdown...

Were you actually implying some auto database reconnect of the current DRDA 
threads created in the network server once the Derby engine or/and databases 
are brought back up?

> Network server may abandon sessions when Derby system is shutdown and this 
> causes intermittent hangs in the client
> ------------------------------------------------------------------------------------------------------------------
>
>                 Key: DERBY-1326
>                 URL: http://issues.apache.org/jira/browse/DERBY-1326
>             Project: Derby
>          Issue Type: Bug
>          Components: Network Server
>            Reporter: Deepa Remesh
>         Assigned To: Knut Anders Hatlen
>         Attachments: repro1326.java, resolve_DRDConnThread_conflict.diff, 
> Restart.java, sessionMgmt1.diff, 
> sessionMgmt1_and_nosessionsforclosedthreads.diff, 
> unify_NSImpl_instances.diff, withNewThreadAndNoShutdownOfCurrentSession.diff
>
>
> This issue was found when working on DERBY-1219. More details can be found in 
> the comments at http://issues.apache.org/jira/browse/DERBY-1219

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