Dsiable child listener process ..

More than two child listener started for one listener.

[oracle@test1 ~]$ ps -ef|grep tns
oracle 10461 1 0 00:04 ? 00:00:00 /u01/app/oracle/product/11.2.0.1/bin/tnslsnr think -inherit
oracle 10462 10461 0 00:04 ? 00:00:00 /u01/app/oracle/product/11.2.0.1/bin/tnslsnr think -inherit
oracle 10463 10462 0 00:04 ? 00:00:00 /u01/app/oracle/product/11.2.0.1/bin/tnslsnr think -inherit
oracle 10464 10462 0 00:04 ? 00:00:00 /u01/app/oracle/product/11.2.0.1/bin/tnslsnr think -inherit

Solution:

SUBSCRIBE_FOR_NODE_DOWN_EVENT_=OFF