RDF System Management Manual

Table Of Contents
Zero Lost Transactions (ZLT)
HP NonStop RDF System Management Manual524388-003
16-13
ZLT and RDF Networks
4. Start TMF.
5. Initiate TMF file recovery with the MAT position option, where the position you
specify is the MAT position reported in the RDF 888 event on the backup
system. Note that the RDF event 888 is logged when the takeover operation
completes.
3. For information about how to return your application processing to the former
primary system, see Carrying Out a Planned Switchover in section 5.
ZLT and RDF Networks
If you have an RDF network and also want ZLT protection on any of the nodes in that
network, then every node that participates in a user transaction must be configured for
ZLT protection.
For example, assume that systems \A and \B are both configured as nodes within an
RDF network, and that system \B is also configured for ZLT protection.
If system \A starts a transaction and any updates associated with that transaction are
done on system \B, then system \A also must be configured for ZLT protection.
STOP TMF Operations
Within an RDF environment that is configured for ZLT processing, STOP TMF
operations are handled as follows.
During Normal Operations
If updating is off, the shutdown audit-record is not stored in image trails, and the
monitor, extractor(s), receiver(s), and purger RDF processes stop.
If updating is on, the shutdown audit-record is stored in image trails, and all RDF
processes stop.
During ZLT Takeover Processing
The shutdown audit-record is not stored in image trails, and all RDF processes
continue running.
The goal of ZLT processing is to catch up data as quickly as possible. Thus, there is no
point in stopping RDF processes if a STOP TMF record is found in the master audit-
trail (MAT).