TMF Reference Manual (G06.24+)

TMFCOM Commands
HP NonStop TMF Reference Manual—522418-002
3-12
ABORT TRANSACTION
Security Restrictions
You can issue the ABORT TRANSACTION command only if you are a member of the
super user group.
TMF State Requirement
Before you can enter the ABORT TRANSACTION command, TMF must be started.
Usage Guidelines
Only transactions that are in the active, aborting, or hung state can be aborted using
this command. An active transaction is one that is in progress; an aborting transaction
is one that is being backed out; a hung transaction is one that TMF attempted to abort
but could not.
For best performance when aborting more than one transaction, issue a single ABORT
TRANSACTION command with a list of transactions, rather than multiple ABORT
TRANSACTION commands.
When you specify a list of transactions, the ABORT TRANSACTION command options
apply to all the transactions in the list. TMFCOM prompts you to confirm the whole list
collectively, rather than the specific transactions individually.
If a process fails while performing audited work on a temporary file, a hung transaction
can result. If the transaction affected only temporary files that have now been removed
from the system, issue an ABORT TRANSACTION command with the
IGNOREDATAERRORS option, specifying the hung transaction.
Use the AVOIDHANGING option when you want to remove a hung transaction without
compromising the integrity of data. Use this option, for example, when data integrity is
more important than the availability of a particular set of files.
When you specify AVOIDHANGING, however, the files that are affected by a
transaction that could not be undone are marked “undo-needed”; these files are not
available to any application until a volume or file recovery is done. All applications that
opened the files before they were marked as “undo-needed” receive an error when
they attempt to access those files again.
As an example, suppose you specify AVOIDHANGING in an ABORT TRANSACTION
command for a transaction that affects two files. If the undo operation completes
successfully on the first file but fails on the second file, only the second file is marked
“undo-needed.”
The IGNOREDATAERRORS and AVOIDHANGING options are mutually exclusive, and
cannot both be specified in the same ABORT TRANSACTION command.
Caution. If the transaction also affected any permanent disk files, however, do not use the
IGNOREDATAERRORS option; in this case, IGNOREDATAERRORS can result in data
corruption. Instead, either use the AVOIDHANGING option as discussed in the following
paragraphs, or refrain altogether from entering the ABORT TRANSACTION command.