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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Available Types of Replication to Multiple Backup
Systems
Alternatively, if your two databases must share the same disks, then you must explicitly
specify which files and tables you want replicated by each RDF subsystem. For
erxample, RDF Subsystem 1 would INCLUDE only Primary DB 1, and RDF Subsystem
2 would INCLUDE only Primary DB 2.
Available Types of Replication to Multiple
Backup Systems
RDF allows you to replicate database changes from a single primary system to multiple
backup systems. This makes possible simultaneous read-only access to all of the
backup systems, a capability particularly desirable for query-intensive applications
where a central volatile database can be distributed to several remote systems for local
access by queries.
Replication to multiple backup systems is achieved by establishing multiple RDF
configurations, each protecting the same database on the primary system. As an
example, you might wish to replicate the same data to different backup systems as
follows:
RDF Configuration #1
\A ---------> \B
RDF Configuration #2
\A ---------> \C
RDF Configuration #3
\A ---------> \D
You can also have two RDF configurations replicating two separate databases (DB1
and DB2) from the same primary system to two different backup systems, as follows:
RDF Configuration #1, protecting database DB1
\A ---------> \B
RDF Configuration #2, protecting database DB2
\A ---------> \C
As a third possibility, you can also have two RDF configurations replicating two
separate databases (DB1 and DB2) from the same primary system to the same
backup system, as follows:
RDF Configuration #1, protecting database DB1
\A ---------> \B
RDF Configuration #2, protecting database DB2
\A ---------> \B
In the preceding examples, each RDF configuration operates entirely independently of
the other RDF configuration primaried on the same node; that is, each RDF
configuration has its own extractor and monitor process. In this way, line failures
affecting one configuration may not necessarily affect the others (depending on the
configuration).