Release 10.1B: OpenEdge Replication
User Guide


Enhanced Read-Only mode

When the OpenEdge Replication agent is running, the database is placed into an Enhanced Read-Only mode (ERO). ERO mode enforces user read-only functionality while providing the benefits of OpenEdge Replication multi-user access to a database. For information on what your OpenEdge Replication installation supports, see the "Database access once OpenEdge Replication is running" section.

When the target database is opened and the OpenEdge Replication agent is started, ERO is implicitly set. Any process that connects to the target database cannot make database updates, with the exception of the OpenEdge Replication agent. Any process connected to a target database cannot lock records.

ERO mode, unlike a client’s read-only functionality, is a database server concept. ERO mode offers full database capabilities with a buffer pool, shared buffers, and read-only private buffers. The read-only (-RO) restriction is set at the client side. ERO is a database restriction.

When a failure occurs and the target database transitions to a normal OpenEdge database, all future connections to the target database are full access. All current connections are disconnected; when they reconnect, they are full access. See the "OpenEdge Replication failure processing" section for more information about the transitioning of a target database to a normal OpenEdge database.


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