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
Managing RDF
HP NonStop RDF System Management Manual—524388-003
5-10
TMF Audited Volume Crash
RDF State Transition Failure
Periods during which the RDF updaters (or RDF itself) are either starting or stopping
are known as RDF state transitions. In rare instances, when a primary CPU fails for
an RDF process during execution of a STOP RDF or STOP UPDATE command, not all
RDF processes complete the state transition properly.
To minimize the chance of encountering this kind of failure, avoid CPU reloads during
RDF state transitions. Furthermore, if a CPU failure does occur during a state
transition, carefully review the EMS event log for signs of incorrect behavior. If the
failure occurred while RDF or the updating facility was stopping, check the Process
Pair Directory (PPD) to ensure that the appropriate RDF processes all have stopped; if
they have not, you must stop them manually.
If a state transition failure occurs during execution of a STOP RDF command and the
operation appears to be stalled, manually stop all of the RDF processes by issuing the
following command on both the primary and backup system:
STATUS *, PROG RDF-software-loc.*, STOP
If a state transition failure occurs during execution of a STOP UPDATE command and
the operation appears to be stalled, manually stop all of the RDF updaters by issuing
the following command on the backup system:
STATUS *, PROG RDF-software-loc.RDFUPDO, STOP
TMF Audited Volume Crash
RDF can recover from a crash of a TMF audited volume on the primary or backup
system. If the volume is successfully recovered by volume recovery, then you do not
have to perform any special RDF procedures.
TMF Subsystem Crash on the Primary System
RDF can recover from a TMF crash on the primary system if the TMF volume recovery
operation is successful after the crash. For this recovery, proceed as follows:
1. Stop RDF on the primary system by entering the following command through
RDFCOM:
]STOP RDF
2. Restart TMF by entering the following command sequence through TMFCOM:
~DISABLE DATAVOLS *
~START TMF
Notice that these commands prevent any disk volumes on the local system from
being enabled for TMF operations before starting the subsystem.
Caution. Issuing this command in this situation is only safe, however, if this is the backup
system for a single RDF environment.