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
Introducing RDF
HP NonStop RDF System Management Manual—524388-003
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RDF Subsystem Overview
There are three versions of the RDF product:
1. RDF/IMP (product number T0346) provides online product initialization, online
database synchronization, triple contingency support, subvolume- and file-level
replication, stop-update-to-time (for quiescing the backup database to a stable
state), NonStop SQL/MP big files support, and many other features.
2. RDF/IMPX (product numbers T0346 and T0347) provides the same functionality
as RDF/IMP, but also replication of auxiliary audit trails, support for network
transactions, and lockstep operation.
3. RDF/ZLT (product number T0618) provides zero lost transaction (ZLT) protection
using mirrored disks.
RDF/IMP and IMPX run on either K-series or S-series systems. The ZLT functionality is
only available on S-series hardware, although RDF/ZLT runs correctly on K-series
systems without providing ZLT protection. Versions of the RDF subsystem running on
K-series or S-series systems can interact with versions of the RDF subsystem running
on NonStop Integrity systems. For information about subsystem interoperability as it
relates to your particular version of the RDF subsystem, read the software documenta-
tion supplied with your RDF software.
Before reading further in this manual, you should be familiar with the concepts,
terminology, and functions of the NonStop TMF product. You should know about the
objects on which TMF operates, such as transactions, audit trails, and audit volumes.
You should understand how TMF software uses elements like before-images, after-
images, and control records. In addition, you should also understand the TMF
processes that perform backout, volume recovery, and file recovery. If you are not
familiar with this information, you should read the Introduction to the HP NonStop
Transaction Management Facility (TMF).
RDF Subsystem Overview
RDF maintains a logically replicated database on one or more backup systems by
monitoring changes made to audited tables and files on designated primary system
volumes and applying those changes to corresponding volumes on the backup system.
Although logically the same as the primary database, a backup database is not an
actual physical copy. For those volumes designated to be protected by RDF, the
backup database contains the same data for all committed transactions as in the
primary database.
On the primary system, RDF extractor processes read audit trails (logs maintained by
TMF of all database transactions that affect audited tables and files), and send all audit
information associated with volumes protected by RDF to RDF receiver processes on
the backup system. Each receiver process sorts the audit information and writes it to
the appropriate image trail. RDF updater processes on the backup system read their
image trails and apply the changes to the backup database. An RDF purger process
on the backup system interacts with the updaters to determine when image files can be
purged.