TNS-12542: TNS:address already in use

The research and development said that the database could not be accessed and the database was running normally, so there may be something wrong with the monitoring.

A wave of simple operations is done.

[oracle@entegor-1] $lsnrctl startLSNRCTL for Linux: Version 11.2.0.4.0-Production on 17-AUG-2018 09:04:01Copyright (c) 1991, 2013, Oracle. All rights reserved.Starting / oracle/app/oracle/11.2.0/db_1/bin/tnslsnr: please wait...TNSLSNR for Linux: Version 11.2.0.4.0-ProductionLog messages written to / oracle/app/oracle/diag/tnslsnr/entegor-1/listener/alert/log.xmlError listening on: (ADDRESS= (PROTOCOL=tcp) (HOST=) (PORT=1521)) TNS-12542: TNS:address already in use TNS-12560: TNS:protocol adapter error TNS-00512: Address already in use Linux Error: 98: Address already in useListener failed to start. See the error message (s) above. [root @ entegor-1 ~] # su-grid [grid @ entegor-1 ~] $lsnrctl statusLSNRCTL for Linux: Version 11.2.0.4.0-Production on 17-AUG-2018 09:03:32Copyright (c) 1991, 2013, Oracle. All rights reserved.Connecting to (DESCRIPTION= (ADDRESS= (PROTOCOL=IPC) (KEY=LISTENER)) STATUS of the LISTENER----Alias LISTENERVersion TNSLSNR for Linux: Version 11.2.0.4.0-ProductionStart Date 31-JAN-2018 11:17:57Uptime 197 days 21 hr. 45 min. 34 secTrace Level offSecurity ON: Local OS AuthenticationSNMP OFFListener Parameter File / oracle/app/11.2.0/grid/network/admin/listener.oraListener Log File / oracle/app/grid/diag/tnslsnr/entegor-1/listener/alert/log.xmlListening Endpoints Summary... (DESCRIPTION= (ADDRESS= (PROTOCOL=ipc) (KEY=LISTENER)) (DESCRIPTION= (ADDRESS= (PROTOCOL=tcp) (HOST=6.1.14.125) (PORT=1521)) Services Summary...Service "+ ASM" has 1 instance (s). Instance "+ ASM1", status READY, has 1 handler (s) for this service...The command completed fullness [grid @ entegor-1] $lsnrctl stopLSNRCTL for Linux: Version 11.2.0.4.0-Production on 17-AUG-2018 09:04:16Copyright (c) 1991, 2013, Oracle. All rights reserved.Connecting to (DESCRIPTION= (ADDRESS= (PROTOCOL=IPC) (KEY=LISTENER) The command completed fullness [grid @ entegor-1] $exitlogout [root @ entegor-1] # su-oracle @ entegor-1 ~] $lsnrctl startLSNRCTL for Linux: Version 11.2.0.4.0-Production on 17-AUG-2018 09:04:25Copyright (c) 1991, 2013, Oracle. All rights reserved.Starting / oracle/app/oracle/11.2.0/db_1/bin/tnslsnr: please wait...TNSLSNR for Linux: Version 11.2.0.4.0-ProductionLog messages written to / oracle/app/oracle/diag/tnslsnr/entegor-1/listener/alert/log.xmlListening on: (DESCRIPTION= (ADDRESS= (PROTOCOL=tcp) (HOST=entegor-1) (PORT=1521)) Connecting to (ADDRESS= (PROTOCOL=tcp) (HOST=) (PORT=1521)) STATUS of the LISTENER- -Alias LISTENERVersion TNSLSNR for Linux: Version 11.2.0.4.0-ProductionStart Date 17-AUG-2018 09:04:25Uptime 0 days 0 hr. 0 min. 1 secTrace Level offSecurity ON: Local OS AuthenticationSNMP OFFListener Log File / oracle/app/oracle/diag/tnslsnr/entegor-1/listener/alert/log.xmlListening Endpoints Summary... (DESCRIPTION= (ADDRESS= (PROTOCOL=tcp) (HOST=entegor-1) (PORT=1521) The listener supports no servicesThe command completed fulfilling [oracle @ entegor-1] $lsnrctl statusLSNRCTL for Linux: Version 11.2.0.4.0-Production on 17-AUG-2018 09:14:12Copyright (c) 1991, 2013, Oracle. All rights reserved.Connecting to (ADDRESS= (PROTOCOL=tcp) (HOST=) (PORT=1521)) STATUS of the LISTENER----Alias LISTENERVersion TNSLSNR for Linux: Version 11.2.0.4.0-ProductionStart Date 17-AUG-2018 09:04:25Uptime 0 days 0 hr. 9 min. 46 secTrace Level offSecurity ON: Local OS AuthenticationSNMP OFFListener Log File / oracle/app/oracle/diag/tnslsnr/entegor-1/listener/alert/log.xmlListening Endpoints Summary... (DESCRIPTION= (ADDRESS= (PROTOCOL=tcp) (HOST=entegor-1) (PORT=1521)) Services Summary...Service "+ ASM" has 1 instance (s). Instance "+ ASM1", status READY, has 1 handler (s) for this service...Service "entegor" has 1 instance (s). Instance "entegor1", status READY, has 2 handler (s) for this service...Service "entegorXDB" has 1 instance (s). Instance "entegor1", status READY, has 1 handler (s) for this service...The command completed fulfilling [oracle @ entegor-1 ~] $