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ORA-12154 or TNS-3505 Using EZCONNECT or Hostname Naming Adapter (Doc ID 1925336.1)

Last updated on MARCH 31, 2022

Applies to:

Oracle Net Services - Version to [Release 10.2 to 11.2]
Information in this document applies to any platform.
This document describes an issue where the EZCONNECT or HOSTNAME naming adapter fails with ORA-12154 or TNS-3505. A client using the TNSNAMES adapter with the
same address information is likely to be successful if the issue documented here is the problem.


When using the EZCONNECT or HOSTNAME naming adapter the following errors are thrown:

TNS-12514 TNS: could not resolve the connect identifier specified

TNS-03505:  TNS: Failed to resolve name


Example using the following might fail with an ORA-12154:


SQL*Plus my_user@\"1HOSTNAME:1521/ORCL\"

Enter password:

ERROR: ORA-12154: TNS:could not resolve the connect identifier specified

Using the same information in a tnsnames.ora file will allow a successful connection:





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