IBM Support

Communication link failure when checking out a schema

Technote (troubleshooting)


Problem(Abstract)

When trying to check out a database schema in IBM® Rational® ClearQuest®, the operation fails with [Microsoft][ODBC SQL Driver] Communication link failure.

Symptom

  1. This error is returned when trying to checkout a schema:

    ERROR! SQLExecDirect: RETCODE=-1,State=08501, Native Error=0 SQL statement="delete from m_entitydef where schema_id=<some number> and schema_rev=<another number>"
    [Microsoft][ODBC SQL Driver] Communication link failure

  2. This error is also seen when trying other database activities, such as upgrading a user database:

    ERROR! An error was detected in the middle of upgrading database "SAMPL" to schema "DefectTracking" version 8: SQLTransact SQL_COMMIT: RETCODE=-1,   State=08S01, Native Error=0
    Microsoft][ODBC SQL Server Driver]Communication link failure

Microsoft details the cause of the Communication Link Failure under SQLState 08S01, as an error that occurs when the communication link between the driver and the data source to which the driver was connected failed before the function completed processing.

Cause

Microsoft details the cause of the Communication Link Failure under SQLState 08S01, as an error that occurs when the communication link between the driver and the data source to which the driver was connected failed before the function completed processing.

This is a generic error message, that points to two basic types of causes:

  • network errors, and
  • database corruption.
When SQL Server closes the connection of the client, for some reason, the client fails to receive the notification from SQL Server. As the client believes the connection is still open because it did not close the connection, it will try to reuse the same connection without reconnecting, which causes the error.

This message typically is not a problem with SQL Server or the driver, but the underlying network - mostly related to network communications; termination of connection, network outage, firewall configuration, hardware or cabling issue, such as a faulty network card, hub or cable.

Diagnosing the problem

DBMON Tracing also shows:

[CQ 46.250, 1608, 223] [Microsoft][ODBC SQL Server Driver][SQL Server]Location: q:\SPHINX\NTDBMS\storeng\drs\include\record.inl:14


Resolving the problem


IMPORTANT ADVISORY: Work with network and SQL Server administrators to see if there were any system problems during the database action. You need to contact Microsoft Support and or your administrators to resolve this, as you may need to restore the ClearQuest databases from a backup taken just prior to the database change.


Database or Table Corruption

Move the database using the ClearQuest Move Tool. Moving the database will rebuild the corrupt table or tables.

  • For a schema repository, use the ClearQuest Maintenance Tool.

  • For a user database, use the Designer Tool.


Rational ClearQuest Documentation

Consult the ClearQuest Information Center for more information about moving databases.


BACKING UP FILES

Always make new database back-ups of your schema repository and user databases prior to making schema changes and performing database upgrades. Failure to create back-up copies can limit your ability to recover from a an upgrade failure, design change issues or other unforeseen failures.

Document information

More support for: Rational ClearQuest
General Information

Software version: 7.0, 7.0.0.1, 7.0.0.2, 7.0.0.3, 7.0.0.4, 7.0.1, 7.0.1.1, 7.0.1.2, 7.0.1.3, 2003.06.00, 2003.06.12, 2003.06.13, 2003.06.14, 2003.06.15, 2003.06.16

Operating system(s): Windows

Reference #: 1131540

Modified date: 25 July 2008