You can get ” ORA-28040: No matching authentication protocol ” error because of Oracle Client incompatibility when you upgrade Oracle database from 11g to 12c or Oracle 18c, 19c,
ORA-28040: No matching authentication protocol 19c
If you get ORA-28040 error When you connect to Oracle 19c database then change your sqlnet.ora file like below. Add these two lines to the sqlnet.ora
SQLNET.ALLOWED_LOGON_VERSION_SERVER=8
SQLNET.ALLOWED_LOGON_VERSION_CLIENT=8
[oracle@MehmetSalih ~]$ ps -ef | grep smon oracle 25167 17807 0 11:56 pts/0 00:00:00 grep --color=auto smon oracle 28385 1 0 10:31 ? 00:00:00 ora_smon_DEVECI19C [oracle@MehmetSalih ~]$ [oracle@MehmetSalih ~]$ [oracle@MehmetSalih ~]$ cd $ORACLE_HOME [oracle@MehmetSalih install]$ cd network/admin/ [oracle@MehmetSalih admin]$ [oracle@MehmetSalih admin]$ cat sqlnet.ora # sqlnet.ora Network Configuration File: /oradata/install/network/admin/sqlnet.ora # Generated by Oracle configuration tools. NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT) SQLNET.ALLOWED_LOGON_VERSION_SERVER=8 SQLNET.ALLOWED_LOGON_VERSION_CLIENT=8
SQLNET.ORA
If you change sqlnet.ora file which is under the $ORACLE_HOME/network/admin then reload your listener like below. And try to connect again.
[oracle@MehmetSalih admin]$ lsnrctl reload LSNRCTL for Linux: Version 19.0.0.0.0 - Production on 01-MAR-2019 11:57:26 Copyright (c) 1991, 2018, Oracle. All rights reserved. Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521)) The command completed successfully [oracle@MehmetSalih admin]$ [oracle@MehmetSalih admin]$ [oracle@MehmetSalih admin]$ lsnrctl status LSNRCTL for Linux: Version 19.0.0.0.0 - Production on 01-MAR-2019 11:57:30 Copyright (c) 1991, 2018, Oracle. All rights reserved. Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521)) STATUS of the LISTENER ------------------------ Alias LISTENER Version TNSLSNR for Linux: Version 19.0.0.0.0 - Production Start Date 01-MAR-2019 11:46:57 Uptime 0 days 0 hr. 10 min. 32 sec Trace Level off Security ON: Local OS Authentication SNMP OFF Listener Log File /u01/app/oracle/diag/tnslsnr/MehmetSalih/listener/alert/log.xml Listening Endpoints Summary... (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=MehmetSalih.DeveciDomain)(PORT=1521))) (DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=MehmetSalih.DeveciDomain)(PORT=5500))(Security=(my_wallet_directory=/u01/app/oracle/admin/DEVECI19C/xdb_wallet))(Presentation=HTTP)(Session=RAW)) Services Summary... Service "DEVECI19C.DeveciDomain" has 1 instance(s). Instance "DEVECI19C", status READY, has 1 handler(s) for this service... Service "DEVECI19CXDB.DeveciDomain" has 1 instance(s). Instance "DEVECI19C", status READY, has 1 handler(s) for this service... The command completed successfully [oracle@MehmetSalih admin]$
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