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
Entering RDFCOM Commands
HP NonStop RDF System Management Manual—524388-003
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Command Overview
Rel Byte No
The seventh column specifies where in the specified file the particular process is
currently reading.
If RDFCOM cannot connect to a particular process, RDFCOM displays dots (...) in the
RTD Time, Sequence, and Rel Byte No fields, and an appropriate file-system error
number in the Error field.
Cpus
The eighth column specifies the CPUs in which each process pair is running.
Error
The final column lets you know if an updater process has experienced a critical error.
If the column is blank, no error has occurred. If the column contains asterisks (*****),
the updater process has experienced a critical error. If the updater is performing an
undo pass for takeover or stop-update-to-time, the column contains undo. The
occurrence of a critical error could mean that the backup database is no longer
synchronized with the primary database due to data loss. If asterisks appear in the
Error column for any RDF process, you should examine the messages in the RDF log
file or on the RDF log device to determine what is happening and what corrective
action to take.
Asterisks in the Error column continue to appear in every STATUS RDF display until
the error condition has been corrected.
The asterisks will also disappear for updater processes when updating is restarted
after execution of any of the following commands:
•
STOP UPDATE
•
STOP RDF
•
STOP TMF
Note that although the occurrence of a critical error might mean that the primary and
backup databases are no longer synchronized with one another, that is not always the
case. If, for example, the primary CPU of the disk process goes down, all updater
processes affected by that error condition report a file system error and then attempt to
restart. If the error does not occur again when the affected updater processes restart,
the databases are probably still synchronized with one another. In that case, the
asterisks are cleared from subsequent STATUS RDF displays.
For more information on critical errors, you can scan the EMS collectors on the primary
and backup systems:
•
The EMS collector on the primary system contains log messages for the extractor
and monitor processes.
•
The EMS collector on the backup system contains log messages for the receiver,
purger, and all updater processes.