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
Network Transactions
HP NonStop RDF System Management Manual—524388-003
13-5
RDF Network Synchronizer (RDFNET) Process
RDF Network Synchronizer (RDFNET) Process
RDF/IMPX and RDF/ZLT include an RDF executable process, the RDFNET process,
that can only be configured within a network master RDF subsystem (and can
therefore only be started on the network master’s primary system).
This process provides a synchronization point within the image trails of all backup
systems in an RDF network. The process does that by updating an audited file named
ZRDFNETX on the primary system of each RDF subsystem in the RDF network. The
overhead of this process should be transparent because the RDFNET process only
starts a single transaction every 15 seconds and only executes a single update against
the ZRDFNETX file on the primary system of each RDF subsystem in the RDF
network.
The fully-qualified name of the ZRDFNETX file for each system is:
$<volume-name>.<subvolume-name>.ZRDFNETX
where <volume-name> is the configured PNETTXVOLUME network attribute and
<subvolume-name> is the configured REMOTECONTROLSUBVOLUME network
attribute.
RDF Network Control Files
The following control files exist in the Master Image Trail (MIT) subvolume of all RDF
subsystems that are configured for replication of network transactions: ZRDFLCMT,
ZRDFLCM2, and ZNETUNDO. Additionally, the network master has three more files:
ZRDFNMTX, ZRDFNMT2, ZRDFNMT3. These files contain internal information that
RDF needs to correctly execute takeover operations involving an RDF network. The
files are empty until you actually initiate a takeover operation on a backup system
within an RDF network.
Normal RDF Processing Within a Network
Environment
Each RDF subsystem within an RDF network conducts its processing individually, as
though it were not involved in an RDF network. That is, for a given RDF subsystem,
the extractors read the MAT and auxiliary audit trails and send data to the receivers.
The updaters read their data from their image trails and apply it to their
UpdateVolumes. During normal processing, no RDF subsystem (except the RDFNET
process within the network master primary system) interacts with any other RDF
subsystem in the RDF network. Therefore, the performance of an individual RDF
subsystem is unaffected by its inclusion within an RDF network.