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HP Reliable Transaction Router User Manual

Page 81

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The RTR System Management Environment

Transaction journal state describes how a transaction progresses

from the point of view of the RTR journal. The transaction

journal state, not seen by frontends and routers, managed by

the backend, is used by RTR for recovery replay of a transaction

after a failure.
Transaction server state, also managed by the backend, describes

how a transaction progresses from the point of view of the

server. RTR uses this state to determine if a server is available

to process a new transaction, or if a server has voted on a

particular transaction.
The RTR SHOW TRANSACTION command shows transaction

status, and the RTR SET TRANSACTION command can be

used, under certain well-constrained circumstances, to change

the state of a live transaction. For more details on use of SHOW

and SET commands, refer to the HP Reliable Transaction Router

System Manager’s Manual.

Partition
Management

As illustrated in Figure 1–18, you can use key ranges in your

application with RTR data-content routing to route transactions

to specific database partitions.
Partitions exist for each range of values in the routing key for

which a server is available to process transactions. Redundant

instances of partitions can be started in a distributed network,

to which RTR automatically manages the state and flow of

transactions. Partitions and their characterisitcs can be defined

by the system manager or operator independently of the

application, as well as within application programs.
RTR management functions enable the system manager or C++

application operation to manage many partition-based attributes

and functions including:
• Creation/deletion of a partition with a user-specified name
• Defining/changing a key-range definition
• Selecting a preferred primary node
• Selecting failover precedence between local and cross-site

shadows

• Suspending/resuming operations to synchronize database

backup with transaction flow

The RTR Environment 5–5