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
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Loopback Configuration (Single System)
systems are likely to be, depending on the image file rollover rate expected at your
site. (RETAINCOUNT should always be the same value on both backup systems.)
To achieve this type of protection, it is imperative that you carefully follow the
instructions presented in Section 10, Triple Contingency.
Loopback Configuration (Single System)
A loopback configuration is one where the primary and backup systems are the same
system. This configuration is of no use in a disaster protection plan, but can be useful
for testing purposes. One set of disks can be replicated to another set of target disks
to provide a copy of the live database. There are two operational considerations
unique to this environment:
•
The updaters operate in transaction mode, which means you should not stop TMF
before stopping RDF.
•
The RDF takeover operation cannot be performed unless you manually stop the
monitor and extractor processes before issuing the TAKEOVER command or
include the ! option in the TAKEOVER command.
Online Product Initialization
You can initialize RDF/IMP, IMPX, or ZLT while your applications continue to run. This
is particularly useful for installing new versions of RDF into existing production
environments where you cannot afford to stop your applications even briefly to
generate a TMF shutdown timestamp. It is also useful if you encounter a problem for
which you would like to reinitialize RDF without stopping your applications.
For information about this capability, see Initializating RDF Without Stopping TMF,
Online Installation and Initialization Without Stopping RDF, and the INITIALIZE RDF
command description.
Online Database Synchronization
With RDF/IMP, IMPX, or ZLT you can synchronize entire databases or selected
volumes, files, tables or even partitions while your applications continue to run. For
information about this capability, see Section 7, Online Database Synchronization.
Online Dumps
With RDF/IMP, IMPX, or ZLT, all backup databases are audited by TMF. You can take
online dumps of a backup database at any time, thereby minimizing the amount of time
necessary to perform any subsequent takeover operation. For information about taking
dumps while the updaters are running, see Section 5, Managing RDF.