I apologise for the scarcity of information here but this is reaching areas well beyond my knowledge so I hope someone might be able to help.
I am frequently (though not always) getting connection errors of the form:
reported in my Tomcat log files on tcServer startup. This seems to indicate an "ORA-12505: TNS:listener does not currently know of SID given in connect descriptor" error.
Caused by: javax.naming.NamingException: Io exception: Connection refused(DESCRIPTION=(TMP=)(VSNNUM=168822016)(ERR=12505)(ERROR_STACK=(ERROR=(CODE=12505)(EMFI=4))))
I have 3 data sources configured in each of 2 tcServer instances. After having these problems with data sources configured via the GUI I reverted to as close as I can get to those configured in other standalone Tomcat 6.0.18 instances which don't exhibit the problem.
I see that ORA-12505 would seem to have a few potential causes. I'm pretty confident that the data source resources are configured correctly since the problems do not always occur with tcServer and appear never to occur with plain Tomcat.
Once the problem has occurred I then get "ORA-12516: TNS:listener could not find available handler with matching protocol stack" when attempting to connect to the database at all (such as via SQL-Plus).
An example of the <Resource> element defining the data source (I've put this in context.xml to mirror the situation with my plain Tomcat instances) is:
The other 2 sources are very similar. Note that the above is simply from my investigations with Tomcat (which I was unfamiliar with until recently) and not in any way optimised for a production environment.
validationQuery="select 1 from dual" />
I see the same thing if I have my data sources configured in server.xml and referenced by <ResourceLink> elements in context.xml as is the case when configuring the sources via the AMS (the context.xml entries are manually entered in this case as per a previous thread).
These problems may potentially be within our database but I'm no DBA and things seem to be fine using the same data source configurations in the plain Tomcat instances so I wonder whether those I have in tcServer are not cleaning up neatly after themselves.
I know there are a lot of unknowns here but would appreciate if anyone has pointers for me to consider next or to know whether anyone else has experienced similar difficulties.