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
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RDF and NonStop SQL/MP DDL Operations
RDF and NonStop SQL/MP DDL Operations
When certain Data Definition Language (DDL) operations are performed on NonStop
SQL/MP tables protected by RDF, applications that depend on these operations are
briefly denied access to the database while the DDL operations are in progress. These
periods of unavailability, commonly called outages, end when the DDL operation
completes.
When you perform NonStop SQL/MP DDL operations such as the following, you can
either include or omit the WITH SHARED ACCESS option:
•
The CREATE INDEX statement, used when creating an index on a table
•
The MOVE clause of the ALTER TABLE or ALTER INDEX statement, used when
moving, splitting, or merging disk file partitions, or when moving boundaries within
partitions
To determine all of the NonStop SQL/MP DDL operations that can be performed WITH
SHARED ACCESS, refer to the HP NonStop SQL/MP Reference Manual.
When included, the WITH SHARED ACCESS option specifies that the DDL operation
is to allow concurrent read-write Data Manipulation Language (DML) access and read-
only utility access to the objects on which it operates during all but the final phase of
the operation. For this reason, operations specifying the WITH SHARED ACCESS
option are sometimes referred to as Online DDL operations.
The only operations that must be performed WITH SHARED ACCESS are merge
partitions and move boundaries. It is recommended that you perform all other
operations with non-shared access.
Performing Non-Shared Access DDL Operations
For DDL operations that do not include the WITH SHARED ACCESS option, you can
minimize outage for the primary system applications as follows:
1. Stop the applications that use the database being protected by RDF.
2. Stop TMF on the primary system.
3. Wait for RDF to stop.
4. Start TMF.
5. Start RDF with updating disabled.
6. Perform the DDL operations on the primary system.
7. Restart the applications.
8. Perform the same DDL operations on the backup system.
9. Issue an RDFCOM START UPDATE command.