Database Reference
In-Depth Information
Database issues
The database connectivity issues are either due to incorrect drivers or network con-
nectivity. It's easy to identify using the simple telnet command test to check that your
application(s) servers have allowed the network route to make the connection to the
database server(s). One must perform telnet tests for all the possible client-server
connections between the application and the database servers. In this scenario, all
the application servers are clients and the database servers are servers for the telnet
tests. It is a leading practice to perform this test for a newly deployed SOA composite
application platform.
On the other hand, please pick the database driver library that works and delivers
load sharing and auto recovery from failover and failback of a database server node
for a database cluster with more than two server nodes. It is a leading practice to
validate load sharing, failover, and failback scenarios to rollout for production runtime
and perform this validation every time you are either updating the database driver or
database server technology.
We often fail to establish the worst case scenarios for all the database connections
needed by all the application server(s) and batch server(s). When this happens, you
will notice that the application server(s) are not able to create database connections
randomly. In order to avoid this, one needs to understand the maximum database
connections needed from all kinds of users such as application server(s), batch serv-
er(s), and power users such as DBA, support and business analyst. JDBC connection
pools must be analyzed for possible maximum sizes instead of just initial or average
connections normally established to the database platform.
