Once the Endeca Server cluster is started, it activates the Endeca
data domain clusters it is hosting. This topic discusses the behavior of the
data domain cluster at startup.
On startup, the
following actions take place:
- Any data domain node is
started in either a leader or follower mode and in any order. Any number of
follower nodes and zero or one leader node are started in each data domain
cluster.
- Once started, each data
domain node registers with the Cluster Coordinator that manages the distributed
state of the cluster. The leader node determines the current version of the
index and informs the Cluster Coordinator.
- Follower nodes do not alter
the index in any way; they continue answering queries based on the version of
the index to which they have access at startup, even if the leader node is in
the process of updating, merging, or deleting index versions on disk. Follower
nodes do not receive updating requests. Follower nodes acquire access to the
new index once the update completes. For information, see
How updates are processed.