[Oracle@bys3 log]$ lsnrctl
LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 06-DEC-2013 10:27:11
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Welcome to LSNRCTL, type "help" for information.
LSNRCTL> show log_file
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bys3.bys.com)(PORT=1521)))
LISTENER parameter "log_file" set to /u01/diag/tnslsnr/bys3/listener/alert/log.xml
The command completed successfully
LSNRCTL> show log_status
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bys3.bys.com)(PORT=1521)))
LISTENER parameter "log_status" set to ON
The command completed successfully
从监听里用show log_file得出日志文件的地址 ---测试机没怎么用依然有8M大小的日志
[oracle@bys3 alert]$ du -sh log.xml
8.0M log.xml
LSNRCTL> set log_status off
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bys3.bys.com)(PORT=1521)))
LISTENER parameter "log_statu". Try "help"

[oracle@bys3 alert]$ mv log.xml log.xmla
LSNRCTL> set log_status on
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bys3.bys.com)(PORT=1521)))
LISTENER parameter "log_status" set to ON
The command completed successfully
LSNRCTL> show log_file
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bys3.bys.com)(PORT=1521)))
LISTENER parameter "log_file" set to /u01/diag/tnslsnr/bys3/listener/alert/log.xml
The command completed successfully
[oracle@bys3 alert]$ ls
log.xml log.xmla