RDF System Management Manual for J-series and H-series RVUs (RDF 1.10)

TMFCOM ABORT TRANSACTION With AVOIDHANGING Option on Primary System
Under some circumstances, the TMF Backout process on the primary system is not able to back out
transactions from a data file (for example, hung transactions). If this situation arises, and if the file
is protected by RDF, the user should avoid issuing the TMFCOM ABORT TRANSACTION command
with the AVOIDHANGING option to abort such transactions. Use of this command makes RDF
write internal entries into the ZFILEINC file on the backup RDF system, thereby stopping the purger
from purging old image trail files thereafter. For details about the ZFILEINC file, see “RDF System
Files” (page 343).
If possible, the user should try to resolve the cause of the Backout errors first (for example, ALTER
MAXEXTENTS of the file if it is an error 45) and then issue TMFCOM ABORT TRANSACTION
without any option.
If RDF internal entries are written into the ZFILEINC file due to the TMFCOM ABORT TRANSACTION
command with the AVOIDHANGING option, then a "brute force" method can be used to restart
the purger activity. That is, perform a PURGEDATA operation on the ZFILEINC file. This method is
to be used only if the user has resolved the hung transactions on the primary system without File
Recovery or Volume Recovery, and if the transactions associated with entries in the ZFILEINC file
would never need to be undone on the backup system.
CAUTION: If the transaction associated to an RDF internal entry listed in the ZFILEINC file needs
to be undone as a part of an RDF TAKEOVER operation, then using the above-described brute
force method might corrupt the database on the backup system. It might also affect the
Stop-Update-To-Time operations.
Audit Trails Pinned by RDF on the Primary System
When you start RDF, the extractor pins the audit trail file it is currently reading in order to prevent
TMF from rolling that file over. This operation of pinning the audit trail file by the extractor is
particularly useful if the extractor falls behind for some reason in that it keeps that audit trail file in
place for the extractor, thereby allowing the extractor to resume operations immediately when the
cause for it falling behind has been resolved.
When the extractor pins an audit trail file, it does this by sending a message to TMF, asking TMF
to keep the file pinned until the extractor no longer needs it, so in reality it is TMF who actually
pins the file on behalf of RDF. When the extractor rolls over from one audit trail file to the next, it
unpins the earlier file and pins the next file.
NOTE: TMF keeps the extractor's audit trail file pinned even if you stop RDF. This ensures that
the file is in the audit trail for the extractor when you next start RDF.
If TMF has an audit trail file pinned and it wants to roll over that file, then it generates a TMF event
to indicate that it cannot unpin the file because it is keeping the file pinned on behalf of RDF. In
this event, TMF includes in that event the name of the RDF control subvolume for the RDF subsystem
that wants the file pinned. Thus you can always determine which RDF subsystem is holding up TMF.
If the extractor has an audit trail file pinned, the extractor is either stopped or stalled for some
reason, and this is affecting TMF, there are two ways to unpin the audit trail file.
1. Issue the RDFCOM UNPINAUDIT command. If you have only one RDF subsystem configured
on your primary system and the control subvolume is the name of the primary system, then
this is a simple operation. If, however, you have multiple RDF subsystems configured on the
primary system, each with its own set of extractors, then you may need to issue the UNPIN
audit command for each RDF subsystem. You do this by starting RDFCOM, and then for each
RDF subsystem you issue the OPEN command with the name of RDF subsystem's control
subvolume, and then issue the UNPINAUDIT command. When you have issued the
UNPINAUDIT command for each control subvolume, then the file is unpinned by TMF.
2. Issue the STOP TMF command. While stopping RDF does not unpin an audit trail file, stopping
TMF does.
Responding to Operational Failures 123