HP Reliable Transaction Router - Manual (Page 96)

transactional shadowing
A process by which identical transactional data are written
to separate disks often at separate sites to increase data
availability in the event of site failure. See also disk shadowing.
two-phase commit
A database commit/rollback concept that works in two steps: 1.
The coordinator asks each local recovery manager if it is able
to commit the transaction. 2. If and only if all local recovery
managers agree that they can commit the transaction, the
coordinator commits the transaction. If one or more recovery
managers cannot commit the transaction, then all are told to roll
back the transaction.
Two-phase commit is an all-or-nothing process: either all of a
transaction is committed, or none of it is.
voting
Used in the two-phase commit process to ensure that all servers
agree that a transaction is to be committed to the database.
If all agree, RTR commits the transaction to the database. If
any server votes ‘‘no’’, the transaction is not committed and all
servers roll back the transaction.
WAN
Wide area network.
XA
An X/Open interface used in distributed transaction processing.
An application that is XA-compliant uses the XA interface
between the transaction manager and the resource manager.
RTR is XA-compliant.
Glossary–12