Categories of problem

The following categories of problem (in order of ascending impact on the user) may be encountered by the CICS® log manager:

  1. Those problems within the MVS™ logger that the MVS logger resolves for itself. CICS has no involvement in this category and may only experience the problem as an increase in response times.
  2. Where the MVS logger is unable to satisfy the CICS log manager's request immediately. This problem state can be encountered:

    If either of these conditions occur, CICS issues message DFHLG0771 (for a general log) or DFHLG0777 (for a system log). The CICS log manager retries the request every three seconds until the request is satisfied. Typically, this can take up to a minute.

  3. If the MVS logger fails, CICS is abended. If the system log has not been damaged, a subsequent emergency restart of CICS should succeed.
  4. If a return code implies that the CICS system log has been damaged, CICS is quiesced, meaning transactions are allowed to run to completion as far as possible, with no further records being written to the system log. To get CICS back into production, you must perform an initial start. However, before doing so you may want to perform a diagnostic run, to gather information for problem diagnosis--see Dealing with a corrupt system log.

    If a return code implies damage to a forward recovery log or autojournal, all files using the log stream are quiesced and their transactions run to completion. Message DFHFC4800, DFHFC4801, or DFHFC4802 is issued. User transactions writing journal records to the log stream experience a write error. For a forward recovery log, before you can continue to use the log stream, you must:

    1. Take an image copy of all data sets referencing the log stream.
    2. Redefine the log stream.
    3. Unquiesce the data sets using the affected logs. You may then explicitly open the files but they open automatically at the first READ or WRITE if they are in a CLOSED ENABLED state after the unquiesce.

    For an autojournal, before you can continue to use the log stream, you must:

    1. Try to read and recover data from the damaged autojournal.
    2. Redefine the log stream.

Related concepts
Coupling facility log streams
Exceeding the capacity of a log stream
How CICS checks for the availability of the MVS logger
Some conditions that cause CICS log manager error messages
Related tasks
Monitoring the logger environment
Defining system and general log streams
Tuning for DASD-only logging
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