Cluster Types

[Ajin_1]

Hi Experts

What is the difference between metro cluster ,continental cluster and extended cambus cluster.

Thanks in Advance

[Matti_Kurkela · Accepted solution]

These are disaster-tolerant solutions of varying levels, designed to provide automatic failover if an entire datacenter goes down (because of fire, flooding, storm damage, bombing, major industrial accident etc.).

• Extended Campus Cluster: Cluster may be split into two separate data centers, located within 100 km of each other. (It removes the basic Serviceguard requirement that the nodes must be located within the same network segment.) Storage replication is still done with MirrorDisk/UX, i.e. the nodes must be able to access storage in both data centers if storage is replicated at all. (Not replicating the storage would create a single point of failure. But if your storage is well-protected in some other way, it is technically *possible* to skip storage replication.)
• Metrocluster: In addition to Extended Campus Cluster, responsibility of storage replication is pushed to the SAN array, so cluster nodes need only access the storage of their respective local data centers. Array-based data replication solutions like HP Continuous Access (EVA or XP) or EMC Symmetrix Remote Data Facility (SRDF) are used. Allows maximum distances of up to 300 km between the data centers.
• Continentalclusters: a pair of Serviceguard clusters linked across any distance. The most extensive disaster-tolerant solution: includes all the techniques of the Extended Campus Cluster and Metrocluster. No distance limits in the Continentalcluster technology, but you will still need to choose a data replication solution that will satisfy all your requirements (distance between data centers vs. required performance levels vs. required level of data integrity guarantee).