Re: Multiple SQL*Net listener process

Hello all;

>It's possible to have multiple SQL*NET listener process running on one machine
>(ex. on a UNIX machine LIST1 listening on 1521 and LIST2 listening on 1522).
>The same can be achieved by starting a listener and listening on multiple
>ports.

yes, it is possible, and we've been doing just that for over a year now.

>Under what circumstances would one have multiple listener process on one
>machine? Has anyone have an application that requires this?

Here's what happened to us. We created a new instance/database, and added it to our sql*net config. We were now listening for approx 7 databases (I can' recall the exact number) with one listener. Shortly thereafter we started seeing:

	tns-12540: internal limit restriction exceeded
	tns-01158: internal connection limit has been reached, preventing
		dispatcher from connecting

in the listener log file. We called Oracle and opened a TAR. They looked at trace files, dumps etc, but, if I recall correctly, never told us what limit was being reached and what we should do. We could make these errors happen, or make them stop by just starting/stopping any one of the instances that the listener was listening for. In other words, with 6 instances started, there was no problem, but as soon as we would start the 7th, the errors started. So, we decided to create another listner and split the load across the two of them. We've not had the problem since.

David DeWolfe
Systems Programmer III
University of Alaska
<sxdjd_at_orca.alaska.edu> Received on Wed May 08 1996 - 00:00:00 CEST