Oracle listener with multiple ports issue

Hi, I have an listener question that I hope the gurus in this forum can help me out. I have a 9.2 listener on Sun solaris listening on two ports 1521 and 1526. I notice that majority of my remote connections are connected to port 1521 and only a some of them connected via port 1526. My listener is NOT configured for failover or anything like that. My question is, how does this happen? Is there a limit of connections on each dedicated port? Under what circumstance Oracle would force a connection to connect to port 1526 and not 1521? Please advise. Thanks in advance.


ps: all of my client tnsnames.ora are configured with multiple addresses in the address_list (1521 and 1526 respectively)

Couple things to look at:

1. Do you have java processes that are using the JDBC Thin driver? Sometimes the developers can use a URL (host:port:sid) that specifically connect to port 1521. These connections will not use the tnsnames.ora.

2. Do you have load balancing on at the client at the tnsnames.ora.