Database Error Messages

ORA-12171

TNS:could not resolve connect identifier: string

Cause

A connection to a database or other service was requested using a connect identifier, and the connect identifier specified could not be resolved into a connect descriptor using one of the naming methods configured. For example, if the type of connect identifier used was a net service name then the net service name could not be found in a naming method repository, or the repository could not be located or reached.


Action

  • If you are using local naming (TNSNAMES.ORA file):
  • Make sure that "TNSNAMES" is listed as one of the values of the NAMES.DIRECTORY_PATH parameter in the Oracle Net profile (SQLNET.ORA)
  • Verify that a TNSNAMES.ORA file exists and is in the proper directory and is accessible.
  • Check that the net service name used as the connect identifier exists in the TNSNAMES.ORA file.
  • Make sure there are no syntax errors anywhere in the TNSNAMES.ORA file. Look for unmatched parentheses or stray characters. Errors in a TNSNAMES.ORA file may make it unusable.
  • If you are using directory naming:
  • Verify that "LDAP" is listed as one of the values of the NAMES.DIRETORY_PATH parameter in the Oracle Net profile (SQLNET.ORA).
  • Verify that the LDAP directory server is up and that it is accessible.
  • Verify that the net service name or database name used as the connect identifier is configured in the directory.
  • Verify that the default context being used is correct by specifying a fully qualified net service name or a full LDAP DN as the connect identifier
  • If you are using easy connect naming:
  • Verify that "EZCONNECT" is listed as one of the values of the NAMES.DIRETORY_PATH parameter in the Oracle Net profile (SQLNET.ORA).
  • Make sure the host, port and service name specified are correct.
  • Try enclosing the connect identifier in quote marks.

See the Oracle Net Services Administrators Guide or the Oracle operating system specific guide for more information on naming.