Re: Intermittent JDBC connection

From:

Tom Anderson <twic@urchin.earth.li>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 26 May 2010 01:10:16 +0100

Message-ID:

<alpine.DEB.1.10.1005260109130.3075@urchin.earth.li>

On Tue, 25 May 2010, Mike Schilling wrote:

Tom Anderson wrote:

On Mon, 24 May 2010, Mike Schilling wrote:

teser3@hotmail.com wrote:

I am connecting to Oracle 10g RAC using JDBC in Tomcat 6.0.20.
It works around 50% of the time. When it doesnt work it shows this
error message:
IO exception: The Network Adapter could not establish the
connection. Here is my JDBC String:
jdbc:oracle:thin:@(DESCRIPTION=(LOAD_BALANCE=on)
(ADDRESS=(PROTOCOL=TCP)
(HOST=170.11.5.111) (PORT=1521)) (ADDRESS=(PROTOCOL=TCP)
(HOST=170.11.5.112)
(PORT=1521)) (CONNECT_DATA=(SERVICE_NAME=service) (FAILOVER_MODE
=
(TYPE = SELECT) (METHOD = BASIC) (RETRIES = 180) (DELAY
= 5) )))

The above Description parameters I use in my tnsnames.ora and can
successfully connect to the Oracle RAC using SQL Plus with no
issues. I can also successfully ping to the IP addresses with no
issues. I also played around with the JDBC string and added
(FAILOVER=ON)
but still have same issues.

You're connecting to one of two ports, and it works 50% of the time.
What happens if you connect to only one of the ports?

By 'port' do you mean 'address'?

Two TCP ports: Both 1521 on 170.11.5.111 and 1521 on 170.11.5.112.

Oh, i see, you're using the word 'port' in the way it's defined in the
specifications. How unusual :).

I'm wondering if only one of themn is answering.

Definitely something to check.

tom

--
Postmodernism's refusal of master narratives is a neat dodge, but doesn't
get it out of the problem that it offers a master narrative. A teapot
with 'this is not a teapot' stencilled on the side will still hold your
PG Tips. -- G'