Each clustered system that uses SAN fabric
switches can use shortwave or longwave optical fiber connections connect to application hosts,
storage systems, or remote
systems.
The maximum distance between the system and host or the system and the storage system depends on the Fibre Channel
speed and cable type. For all speeds and cable types, the maximum distance is 300 m for shortwave
optical connections and 10 km for longwave optical connections. Longer distances are supported between systems that use the intersystem Metro
Mirror or Global
Mirror feature.
When you use longwave optical
fiber connections, follow these guidelines:
- For disaster recovery, each system must be regarded as a single entity, which
includes the storage system that
provides the quorum disks for the system. Therefore, the system and quorum disks must be co-located.
The maximum distance between nodes within a system is 100 meters. There can be a large fiber-cable distance between the
same nodes in the system.
However, the nodes must be
physically co-located for effective service and maintenance.
For example, the nodes
can be 300 meters away for 2 Gbs connections. For 4 Gbs connections, nodes can be 150 meters away from the SAN fabric. In
both configurations, the maximum cable distance between the nodes is 600 meters. However, the nodes must be physically within 100 meters of each
other.
- All nodes in a system must be on the same IP subnet so that the nodes can assume the same system or service IP
address.