Host attachment communication requirements

This list describes requirements and other considerations for connecting host attachments in your network.

  • You must use worldwide port names to uniquely identify fibre-channel adapter cards that are installed in your host system.
  • For open-system hosts with fibre-channel adapters, keep in mind that fibre channel architecture provides a variety of communication protocols. Each interconnected storage unit within the architecture is referred to as a node, and each host is also a node. Each node corresponds to one or more ports. (In the case of fibre-channel I/O adapters, these ports are fibre-channel ports.) Each port attaches to a serial-transmission medium that provides duplex communication with the node at the other end of the medium. You can configure your network structure based on one of three basic interconnection topologies (network structures):
    • Point-to-point
    • Switched fabric
    • Arbitrated loop
  • The maximum distance between a host fibre-channel port and the following network components is 300 meters (984 ft) with a shortwave adapter and 10 km (6.2 miles) with a longwave adapter.
    • Fabric switches
    • Fabric hubs
    • Link extenders
    • Storage unit fibre-channel port
    The maximum distance might be greater than 10 km (6.2 miles) when a link extender provides target initiator functions or controller emulation functions.
    Note: Do not use link extenders with emulation functions on links over which Remote Mirror and Copy operations are performed. This is because of the additional path delay that is introduced by these units.
  • Because the fibre channel architecture allows any fibre-channel initiator to access any fibre-channel device, without access restrictions, this can represent a security exposure. You must set the fibre-channel access modes to the proper setting.
Related tasks
Network configurations
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