oracle数据库连接hang，出现了两个listener，一个是另一个子进程
oracle数据库连接hang，出现了两个listener，一个是另一个子进程
处理过程如下
1，出现问题时，用户连接hang住，出现两个listener，现有连接无问题
$ ps -ef|grep lsnr
  oracle 26327    1  0 12月 24  ?        5:34 /oracle/product/10.2.0.1/bin/tnslsnr listener -inherit
  oracle 16352 12931  1 10:44:26 pts/4    0:00 grep lsnr
  oracle 28413 26327  0 21:40:46 ?        0:00 /oracle/product/10.2.0.1/bin/tnslsnr listener -inherit
  patrol 29576 29575  0 21:45:19 ?        0:00 /oracle/product/10.2.0.1/bin/lsnrctl stat listener
2，为快速恢复问题，杀掉进程
$ kill -9 26327
3，重启
$ lsnrctl start
lsnrctl for hpux: version 10.2.0.1.0 - production on 26-dec-2012 10:44:54
copyright (c) 1991, 2005, oracle.  all rights reserved.
starting /oracle/product/10.2.0.1/bin/tnslsnr: please wait...
tnslsnr for hpux: version 10.2.0.1.0 - production
system parameter file is /oracle/product/10.2.0.1/network/admin/listener.ora
log messages written to /oracle/product/10.2.0.1/network/log/listener.log
listening on: (description=(address=(protocol=tcp)(host=rps02)(port=1521)))
listening on: (description=(address=(protocol=ipc)(key=extproc0)))
connecting to (description=(address=(protocol=tcp)(host=rps02)(port=1521)))
status of the listener
------------------------
alias                    listener
version                  tnslsnr for hpux: version 10.2.0.1.0 - production
start date                26-dec-2012 10:44:56
uptime                    0 days 0 hr. 0 min. 0 sec
trace level              off
security                  on: local os authentication
snmp                      on
listener parameter file  /oracle/product/10.2.0.1/network/admin/listener.ora
listener log file        /oracle/product/10.2.0.1/network/log/listener.log
listening endpoints summary...
  (description=(address=(protocol=tcp)(host=rps02)(port=1521)))
  (description=(address=(protocol=ipc)(key=extproc0)))
services summary...
service plsextproc has 1 instance(s).
  instance plsextproc, status unknown, has 1 handler(s) for this service...
the command completed successfully
4，恢复正常，只有一个listener
$
$ ps -ef|grep lsnr
  oracle 16503    1  0 10:44:56 ?        0:00 /oracle/product/10.2.0.1/bin/tnslsnr listener -inherit
  oracle 17637 12931  1 10:48:17 pts/4    0:00 grep lsnr
$
5，后续查询metalink，基本确定为bug，需打oracle  patch 4518443
详见文件intermittent tns listener hang, new child listener process forked [id 340091.1]
除了打补丁，oracle给出的其它解决方案是
a,修改listener.ora文件
subscribe_for_node_down_event_=off
b,移动ons.config文件
cd $oracle_home/opmn/conf
mv ons.config ons.config.ori
，