User`s guide

About Port Clustering
Chapter 15 Port Clustering 221
Peer-to-Peer Clustering
Peer-to-peer clustering allows multiple Digi Passport units to share
information and have equal status within a cluster, without requiring one of
the units to be the master. Any unit in the cluster, typically, the closest unit
to the user, can act as a master. This avoids the single point of failure
associated with "centralized system" control -- with peer-to-peer clustering,
each unit is capable of initiating connections to ports on any other unit,
avoiding the "what if that unit is unreachable?" problem. Peer-to-peer
clustered units can also control slave units as well, allowing for a more
scalable and robust implementation, since if any one unit is offline, there is
no single point of failure to reach the other units.
Users can access use any peer in peer-to-peer group to access any peer
or its slave units. It extends the limitation of clustering slave units. A master
unit can have up to 48 slave units. 48 peers can join to clustering peer-to-
peer group. If each 48 peer with 48 slave units joins a peer-to-peer group,
2352 units (49 * 48) can be clustered together.
Changes between peered units are updated to the other peers
automatically, even if the peer’s IP address is changed.