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
Preparing the RDF Environment
HP NonStop RDF System Management Manual—524388-003
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Disk Volume Limit
is identical to that of the primary system, your system personnel can adjust more
quickly to the backup environment during disaster recovery.
If you cannot configure the backup system as an identical copy of the primary system,
plan the configuration of the backup system with enough processing power and disk
drives to enable RDF to keep the backup database current with the primary database.
Because RDF only applies database modifications on the backup system, the CPU
requirements on the backup system when running RDF will typically be lower than the
total CPU requirements on the primary system running the applications. The actual
backup CPU requirements depend on many factors, including the RDF configuration,
the rate of audit transmission from the primary system to the backup system, the
database update rate, and whether or not you have copies of your applications
installed (in “standby” mode).
Sizing the RDF configuration is a complex task that is best carried out by HP
personnel. Those personnel can assist you in configuring and sizing your RDF
environment using tools and utilities designed and developed as part of the RDF
Professional Service.
Contact your service provider for further details.
Disk Volume Limit
The RDF/IMP, IMPX, and ZLT products can protect up to 255 physical or virtual
volumes on your primary system, and the updaters for these volumes replicate to
either a single physical or virtual disk on the backup system.
Volume-to-Volume Mapping
The recommended disk drive configuration for RDF products is a one-to-one mapping
between the primary volumes and their corresponding backup volumes, with mirrored
disks on both systems. This one-to-one mapping ensures that each partition of a
partitioned file or table is mapped appropriately to a backup volume.
Volume names on the backup system can differ from those on the primary system, but
the use of identical primary and backup volume names prevents naming conflicts after
a takeover operation. If the names of the backup volumes are different than those of
the corresponding primary volumes, you will need to change all volume references
before the primary system’s applications can start on the backup system.