Hi,
I got ” The Network Adapter could not establish the connection” error in SQL Developer, TOAD and PL/SQL Developer connection for Oracle database.
The Network Adapter could not establish the connection
Details of error are as follows.
java.sql.SQLException: Io exception: The Network Adapter could not establish the connection.
The Network Adapter could not establish the connection error is related with the wrong URL or IP Adress, Service_Name, SID and Port number.
If you got The Network Adapter could not establish the connection error, then check your URL, IP Adress, Port,Service_Name, SID and DNS, If any of them is wrong, then fix it.
If your URL, IP Adress, Port, Service_Name or SID are correct, then check your database listener if it is configured properly or not.
lsnrctl status | lsnrctl stop | lsnrctl start
To solve The Network Adapter could not establish the connection error, type your URL, IP Adress, Port,Service_Name, SID or reload and stop, start your database’s listener as follows.
[oracle@MSDBdbadm01 ~]$ lsnrctl status LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 17-SEP-2020 15:54:45 Copyright (c) 1991, 2014, Oracle. All rights reserved. Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521)) STATUS of the LISTENER ------------------------ Alias LISTENER Version TNSLSNR for Linux: Version 12.1.0.2.0 - Production Start Date 23-JUL-2020 01:45:30 Uptime 56 days 14 hr. 9 min. 15 sec Trace Level off Security ON: Local OS Authentication SNMP OFF Listener Parameter File /u01/app/12.1.0.2/grid/network/admin/listener.ora Listener Log File /u01/app/oracle/diag/tnslsnr/MSDBdbadm01/listener/alert/log.xml Listening Endpoints Summary... (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=LISTENER))) (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.3.16)(PORT=1521))) (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.2.9)(PORT=1521))) Services Summary... Service "+ASM" has 1 instance(s). Instance "+ASM1", status READY, has 1 handler(s) for this service... Service "-MGMTDBXDB" has 1 instance(s). Instance "-MGMTDB", status READY, has 1 handler(s) for this service... Service "MSDB" has 1 instance(s). Instance "MSDB1", status READY, has 1 handler(s) for this service... Service "MSDBXDB" has 1 instance(s). Instance "MSDB1", status READY, has 1 handler(s) for this service... Service "_mgmtdb" has 1 instance(s). Instance "-MGMTDB", status READY, has 1 handler(s) for this service... Service "cluster_clu1" has 1 instance(s). Instance "-MGMTDB", status READY, has 1 handler(s) for this service... The command completed successfully [oracle@MSDBdbadm01 ~]$ [oracle@MSDBdbadm01 ~]$ lsnrctl stop [oracle@MSDBdbadm01 ~]$ lsrnctl start
You should use IP, Port, Service_name as above.
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