RDF System Management Manual
Table Of Contents
- RDF System Management Manual
- What’s New in This Manual
- About This Manual
- 1 Introducing RDF
- RDF Subsystem Overview
- RDF Processes
- RDF Operations
- Reciprocal and Chain Replication
- Available Types of Replication to Multiple Backup Systems
- Triple Contingency
- Loopback Configuration (Single System)
- Online Product Initialization
- Online Database Synchronization
- Online Dumps
- Subvolume- and File-Level Replication
- Shared Access DDL Operations
- EMS Support
- SMF Support
- RTD Warning Thresholds
- Process-Lockstep Operation
- Support for Network Transactions
- RDF and NonStop SQL/MX
- Zero Lost Transactions (ZLT)
- Monitoring RDF Entities With ASAP
- 2 Preparing the RDF Environment
- 3 Installing and Configuring RDF
- 4 Operating and Monitoring RDF
- 5 Managing RDF
- Recovering From File System Errors
- Handling Disk Space Problems
- Responding to Operational Failures
- Stopping RDF
- Restarting RDF
- Carrying Out a Planned Switchover
- Takeover Operations
- Reading the Backup Database
- Access to Backup Databases in a Consistent State
- RDF and NonStop SQL/MP DDL Operations
- RDF and NonStop SQL/MX Operations
- Backing Up Image Trail Files
- Making Online Dumps With Updaters Running
- Doing FUP RELOAD Operations With Updaters Running
- Exception File Optimization
- Switching Disks on Updater UPDATEVOLUMES
- 6 Maintaining the Databases
- 7 Online Database Synchronization
- 8 Entering RDFCOM Commands
- 9 Entering RDFSCAN Commands
- 10 Triple Contingency
- 11 Subvolume- and File-Level Replication
- 12 Auxiliary Audit Trails
- 13 Network Transactions
- Configuration Changes
- RDF Network Control Files
- Normal RDF Processing Within a Network Environment
- RDF Takeovers Within a Network Environment
- Takeover Phase 1 – Local Undo
- Takeover Phase 2 – File Undo
- Takeover Phase 3 – Network Undo
- Takeover Phase 3 Performance
- Communication Failures During Phase 3 Takeover Processing
- Takeover Delays and Purger Restarts
- Takeover Restartability
- Takeover and File Recovery
- The Effects of Undoing Network Transactions
- Takeover and the RETAINCOUNT Value
- Network Configurations and Shared Access NonStop SQL/MP DDL Operations
- Network Validation and Considerations
- RDF Re-Initialization in a Network Environment
- RDF Networks and ABORT or STOP RDF Operations
- RDF Networks and Stop-Update-to-Time Operations
- Sample Configurations
- RDFCOM STATUS Display
- 14 Process-Lockstep Operation
- Starting a Lockstep Operation
- The DoLockstep Procedure
- The Lockstep Transaction
- RDF Lockstep File
- Multiple Concurrent Lockstep Operations
- The Lockstep Gateway Process
- Disabling Lockstep
- Reenabling Lockstep
- Lockstep Performance Ramifications
- Lockstep and Auxiliary Audit Trails
- Lockstep and Network Transactions
- Lockstep Operation Event Messages
- 15 NonStop SQL/MX and RDF
- Including and Excluding SQL/MX Objects
- Obtaining ANSI Object Names From Updater Event Messages
- Creating NonStop SQL/MX Primary and Backup Databases from Scratch
- Creating a NonStop SQL/MX Backup Database From an Existing Primary Database
- Online Database Synchronization With NonStop SQL/MX Objects
- Offline Synchronization for a Single Partition
- Online Synchronization for a Single Partition
- Correcting Incorrect NonStop SQL/MX Name Mapping
- Consideration for Creating Backup Tables
- Restoring to a Specific Location
- Comparing NonStop SQL/MX Tables
- 16 Zero Lost Transactions (ZLT)
- A RDF Command Summary
- B Additional Reference Information
- C Messages
- D Operational Limits
- E Using ASAP
- Index
Maintaining the Databases
HP NonStop RDF System Management Manual—524388-003
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Resynchronizing Databases
2. Stop TMF on the primary system; wait for RDF to read the STOP TMF message in
the audit trail and stop itself.
3. Start TMF on the primary system so the operations on audited Enscribe files can
be performed.
4. Start RDF so that no audit trails are lost, but do not resume application processing.
5. Perform each operation on Enscribe files on the backup system and the
corresponding operation on the primary system.
6. Finally, resume application processing.
Resynchronizing Databases
There are two ways of resynchronizing your primary and backup databases: offline and
online. With offline resynchronization you must first stop your applications and TMF on
the primary system. With online resynchronization, however, you can resynchronize
entire databases, selected volumes, a single volume, or individual tables and files
while your applications continue to run on the primary system.
The remainder of this section describes how to do offline resynchronization. For
information about online resynchronization, see Section 7, Online Database
Synchronization.
For NonStop SQL/MP or NonStop SQL/MX tables with sys-key or cluster-keys, you
must do offline synchronization, as well as for Enscribe unstructured files or any kind of
entry-sequenced file.
To resynchronize the primary and backup databases, you need to make all backup
database files or tables logically identical to the primary database files or tables when
there is no audit data to be processed for the files or tables. If you know which files or
tables are not synchronized, resynchronize the databases only on the volumes that
contain those files or tables.
There is no audit data to be processed for a volume at the following times:
•
Immediately after TMF has been started for the very first time and no applications
have been started yet
•
When the RTD time is zero for the volume’s updater process, and no audit data is
being generated by any application while the files or tables are being duplicated
•
When TMF is stopped (without the ABRUPT option)
Make sure the primary and backup databases are synchronized if any of the following
should occur:
•
A TMF file recovery operation to a timestamp or to first purge occurs, after which
only the affected database tables or files need to be resynchronized.