Re: TOMCAT REALM dosn't work after DB was down

From: X_AWemner_X (mail_at_mail.com)
Date: 10/23/03 

Date: Thu, 23 Oct 2003 09:15:37 +0300

> I think its because the jdbc connection which it creates to do the
> suthentication is no longer valid and it doesn't have the logic to create
> a new connection and try again. Connection pools have the same problem
> under Tomcat.

Is it still so, that current releases of DBCP pooling cannot use "isAlive"
query to verify the connection and drop dead ones?

I think a proper pooling should have at least the following parameters:
isAliveQuery = Select * From Dual (or something else to run a simple query)
isAliveInterval=5 (run isalive every 5sec for acquired connections)

isAliveInterval can be used so that if connection instance is not being used
by clients within given interval, then isalive query is run on it. Dead
instance is dropped and new one created. This will avoid unnecessary isalive
queries if instances is taken from and put back to the pool with rapid
intervals. We will assume it still works if worked fine within last 5
seconds.

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