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For a DS8000 series configuration, you can use SANs to attach storage unit disks
and to attach hosts to the storage unit.
When you connect your DS8000 storage units to a SAN, you must meet the
following requirements:
v
When a SAN is used to attach both disks and hosts to the storage unit, any
storage device that is managed by the storage unit must be visible to the host
systems.
v When concurrent device adapters and I/O adapter operations are supported
through the same I/O port, the SAN attached to the port must provide both
host and device access.
v Fibre Channel I/O adapters must be configured to operate in a point-to-point
mode fabric topology. See the
IBM System Storage DS8000 Host Systems
Attachment Guide , for more information.
Also consider the following facts:
v
Fibre Channel SANs can provide the capability to interconnect open systems and
storage in the same network as System z or S/390 host systems and storage.
v A single Fibre Channel I/O adapter can have physical access to multiple Fibre
Channel ports on the storage unit.
Host attachment communication requirements
This list describes requirements and other considerations for connecting host
attachments in your network.
v
You must use worldwide port names to uniquely identify Fibre Channel adapter
cards that are installed in your host system.
v For open-system hosts with Fibre Channel adapters, keep in mind that Fibre
Channel architecture provides various 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
See the IBM System Storage DS8000 Host Systems Attachment Guide for more
information about these supported topologies.
v
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.
Chapter 6. Meeting DS8000 series delivery and installation requirements
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