Backup and Restore of Lotus Domino/Notes Cluster using Data Protector

HP OpenView Storage Data Protector
Backup & Restore of Lotus Domino Cluster using Data Protector
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4. Overview of Lotus Domino cluster
4.1. Replicas
To make a database available to users in different locations, on different networks,
or in different time zones, replicas are created. If replica of a certain database is
available on one or more local server, then users need not connect to a single
central server. All replicas share a replica ID which is assigned when the database
is first created. The file names of two replicas can be different, and each replica can
contain different documents or have a different database design; however, if their
replica IDs are identical, replication can occur between them. A replica of a
database is different from a copy of a database. Although a copy of a database
may look the same as the original database, it doesn't share a replica ID with the
original database and so it can't replicate with it.
4.2. Replication in a cluster
Cluster replication is event-driven, rather than schedule-driven. When the Cluster
Replicator (a Lotus Domino cluster component) is aware of a change in a database,
it immediately pushes that change to other replicas in the cluster. If there is a
backlog of replication events, the Cluster Replicator stores these in memory until it
can push them to the other cluster servers. If a change to the same database occurs
before a previous change has been sent, the Cluster Replicator pools these changes
and sends them together to save processing time.
Because Domino stores replication events only in memory, both the source and
destination servers must be available for the replication to complete successfully. If a
destination server is not available, the Cluster Replicator continues to store the events
in memory until the destination server becomes available. The Cluster Replicator
attempts periodically to push these replication events to the destination server. The
interval between these attempts starts at one hour and increases over time to a
maximum of one day.
If the source server shuts down before the replication completes, the replication
events in memory are lost. For this reason, standard replication (the REPLICA task)
should be used to perform immediate replication with all members of the cluster
whenever you restart a cluster server. It is also a good idea to schedule replication
between cluster servers on a regular basis, such as several times per day, to ensure
that databases remain synchronized. The Cluster Replicator always attempts to make
all replicas identical so that users who fail over do not notice that they failed over.