如何启动 Oracle 监听器？检查监听器状态：使用命令 lsnrctl status。启动监听器：使用命令 lsnrctl start。验证监听器状态：再次使用命令 lsnrctl status。

如何启动 Oracle 监听器？

启动步骤：

1. 检查监听器状态：使用命令 lsnrctl status 检查监听器状态。如果监听器未运行，将显示以下错误消息：

   LSNRCTL for Linux: Version 12.2.0.1.0 - Production on 29-JAN-2025 10:21:07
   Copyright (c) 1991, 2017, Oracle.  All rights reserved.
   
   Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521)))
   TNS-12541: TNS:no listener

2. 启动监听器：使用命令 lsnrctl start 启动监听器。如果命令成功执行，将显示以下输出：

   LSNRCTL for Linux: Version 12.2.0.1.0 - Production on 29-JAN-2025 10:21:07
   Copyright (c) 1991, 2017, Oracle.  All rights reserved.
   
   Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521)))
   Starting /home/oracle/app/oracle/product/12.2.0/dbhome_1/network/admin/listener.ora

3. 验证监听器状态：再次使用命令 lsnrctl status 验证监听器是否已成功启动。输出将显示监听器正在运行：

   LSNRCTL for Linux: Version 12.2.0.1.0 - Production on 29-JAN-2025 10:21:07
   Copyright (c) 1991, 2017, Oracle.  All rights reserved.
   
   Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521)))
   Status of the LISTENER
   ------------------------
   Alias                     LISTENER
   Version                   12.2.0.1.0
   Start Date                29-JAN-2025 10:21:07
   Uptime                    0 days 0 hr. 0 min. 0 sec
   Trace Level              off
   Security                  ON: Local OS Authentication
   SNMP                      OFF
   Default Service            orcl
   Listener Parameter File   /home/oracle/app/oracle/product/12.2.0/dbhome_1/network/admin/listener.ora
   Listener Log File         /home/oracle/app/oracle/product/12.2.0/dbhome_1/network/log/listener.log
   Listening Endpoints Summary...
   (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1521)))