Inside the listener file we have found that two address entries in the same host and same port number (1524) so starting the listener it will get the conflict so unable to start the database
# lsnrctl start LISTENER_PRODLSNRCTL for Linux: Version 12.1.0.2.0 - Production on 20-AUG-2020 06:15:09Copyright (c) 1991, 2017, Oracle. All rights reserved.Starting /oracle/app/oracle/product/12.1.0.2/dbhome/bin/tnslsnr: please wait...TNSLSNR for Linux: Version 12.1.0.2.0 - ProductionSystem parameter file is /oracle/app/oracle/product/12.1.0.2/dbhome/network/admin/listener.oraLog messages written to /oracle/app/oracle/diag/tnslsnr/dba-host/listener_prod/alert/log.xmlListening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1524)))Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1525)))Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=dba-host)(PORT=1524)))STATUS of the LISTENER------------------------Alias LISTENER_PRODVersion TNSLSNR for Linux: Version 12.1.0.2.0 - ProductionStart Date 20-AUG-2020 06:15:09Uptime 0 days 0 hr. 0 min. 0 secTrace Level offSecurity ON: Local OS AuthenticationSNMP OFFListener Parameter File /oracle/app/oracle/product/12.1.0.2/dbhome/network/admin/listener.oraListener Log File /oracle/app/oracle/diag/tnslsnr/dba-host/listener_prod/alert/log.xmlListening Endpoints Summary... (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1524))) (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1525)))Services Summary...Service "PRODDB" has 1 instance(s). Instance "PRODDB", status UNKNOWN, has 1 handler(s) for this service...The command completed successfullyListener started successfully.
Listener started sucessfully and listener listening in on both the ports 1524 and 1525 so ports should be unique for each address in the listener
To find the solution we need to check the Listener file listener.ora
LISTENER_PROD = (DESCRIPTION_LIST = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = dba-host)(PORT = 1524)) --- >>> (ADDRESS = (PROTOCOL = TCP)(HOST = dba-host)(PORT = 1524)) --- >>> ) ) SID_LIST_LISTENER_PROD = (SID_LIST = (SID_DESC = (SID_NAME = PRODDB) (ORACLE_HOME = /oracle/app/oracle/product/12.1.0.2/dbhome) ) )Inside the listener file we have found that two address entries in the same host and same port number (1524) so starting the listener it will get the conflict so unable to start the database
(ADDRESS = (PROTOCOL = TCP)(HOST = dba-host)(PORT = 1524)) (ADDRESS = (PROTOCOL = TCP)(HOST = dba-host)(PORT = 1524))To fix the error in give different port numbers for both the address entries
The listener will look like this after change the port numbers
LISTENER_PROD = (DESCRIPTION_LIST = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = dba-host)(PORT = 1524)) --- >>> (ADDRESS = (PROTOCOL = TCP)(HOST = dba-host)(PORT = 1525)) --- >>> ) ) SID_LIST_LISTENER_PROD = (SID_LIST = (SID_DESC = (SID_NAME = PRODDB) (ORACLE_HOME = /oracle/app/oracle/product/12.1.0.2/dbhome) ) )Now start the listener
# lsnrctl start LISTENER_PROD LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 20-AUG-2020 06:15:09 Copyright (c) 1991, 2017, Oracle. All rights reserved. Starting /oracle/app/oracle/product/12.1.0.2/dbhome/bin/tnslsnr: please wait... TNSLSNR for Linux: Version 12.1.0.2.0 - Production System parameter file is /oracle/app/oracle/product/12.1.0.2/dbhome/network/admin/listener.ora Log messages written to /oracle/app/oracle/diag/tnslsnr/dba-host/listener_prod/alert/log.xml Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1524))) Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1525))) Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=dba-host)(PORT=1524))) STATUS of the LISTENER ------------------------ Alias LISTENER_PROD Version TNSLSNR for Linux: Version 12.1.0.2.0 - Production Start Date 20-AUG-2020 06:15:09 Uptime 0 days 0 hr. 0 min. 0 sec Trace Level off Security ON: Local OS Authentication SNMP OFF Listener Parameter File /oracle/app/oracle/product/12.1.0.2/dbhome/network/admin/listener.ora Listener Log File /oracle/app/oracle/diag/tnslsnr/dba-host/listener_prod/alert/log.xml Listening Endpoints Summary... (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1524))) (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dba-host)(PORT=1525))) Services Summary... Service "PRODDB" has 1 instance(s). Instance "PRODDB", status UNKNOWN, has 1 handler(s) for this service... The command completed successfully Listener started successfully.Listener started sucessfully and listener listening in on both the ports 1524 and 1525 so ports should be unique for each address in the listener