Compaq Reliable Transaction Router manual Monitoring RTR

The RTR System Management Environment

Monitoring RTR	RTR Monitor pictures or the RTR Monitor let you view the
	status and activities of RTR and your applications. A monitor
	picture is dynamic, its data periodically updated. RTR SHOW
	commands that also let you view status are snapshots, giving
	you a view at one moment in time. A full list of RTR Monitor
	pictures is available in the RTR System Manager's Manual ``RTR
	Monitoring'' chapter and in the help file under RTR_Monitoring.
	Many RTR Monitor pictures are available using the RTR browser
	interface.
Transaction	The RTR transaction is the heart of an RTR application,
Management	and transaction state characterizes the current condition of a
	transaction. As a transaction passes from one state to another, it
	undergoes a state transition. Transaction states are maintained
	in memory, and some are stored in the RTR journal for use in
	recovery.
	RTR uses three transaction states to track transaction status:
	•	transaction runtime state
	•	transaction journal state
	•	transaction server state

Transaction runtime state describes how a transaction progresses from the point of view of RTR roles (FE, TR, BE). A transaction, for example, can be in one state as seen from the frontend, and in another as seen from the router.

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, see the RTR System Manager's Manual.

5–4The RTR Environment