TMF Reference Manual (G06.24+)

TMFCOM Commands
HP NonStop TMF Reference Manual—522418-002
3-257
START TMF
During START TMF operation, volume recovery might not be able to recover some
files. The unrecovered files will not be available when the operation completes but
they will be listed in EMS messages. To make them available, you might need to use
the RECOVER FILES command to perform a file recovery. (To support file recovery, of
course, you must regularly produce online and audit dumps.)
If you issue a STOP TMF command during a start operation, the command might not
take effect immediately; this delay, however, should not be long.
If you do not specify the NOWAIT option, TMFCOM prompts you for a new command
when the start operation is complete.
If you issue a START TMF command immediately after entering a STOP TMF,
ABRUPT command, the start operation might create the new TMP before the old TMF
backout process terminates. Very soon thereafter, the backout process abends but is
not restarted by the new TMP. In this event, aborting transactions are hung. To
recover from this situation, use TMFCOM to enter an ALTER TMF, SWITCHPROCESS
TMP command. As a result, the TMP restarts the backout process and aborting
transactions are completed.
If TMF crashes while unresolved distributed transactions exist in the prepared state
and you subsequently enter a START TMF command, TMF detects those transactions
and the start operation cannot proceed until they are resolved. If the parent node is
now available, TMF automatically resolves those transactions and the start operation
completes. But if the parent node is not available, you must use the RESOLVE
TRANSACTION command to resolve the transactions manually before the start
operation can conclude. For more information about the RESOLVE TRANSACTION
command, see RESOLVE TRANSACTION on page 3-228.
Output Displayed
As startup progresses, TMFCOM displays EMS messages about various events. The
format and content of these messages varies. Many of these messages show the
status (starting or started) of the primary processes for individual TMP components;
these messages can help in analyzing problems that might occur during TMF startup.
Caution. Verify the status of the stop operation after using a STOP TMF command with the
NOWAIT option, but before entering the START command. Enter the DISPLAY OPERATIONS
command to verify that the shutdown was complete; otherwise, damage to your database can
occur during the restart. In the DISPLAY OPERATIONS
command, use the operation number
returned by the STOP TMF command-acceptance message or the appropriate date-time
specification.
If you use the START TMF command with the NOWAIT option, also use DISPLAY
OPERATIONS to verify the status of the start operation.
In addition, if multiple users are accessing your TMFSERVE process through multiple
TMFCOM processes, be sure to communicate your intentions to stop or restart TMF.