HP StorageWorks 4000/6000/8000 - Enterprise Virtual Arrays, Reference Manual

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Topology migration
To increase SAN connectivity and capacity:
• Increase the number of switches.
• Use switches with more ports.
• Implement multiple fabrics.
• Implement Fibre Channel routing.
• Migrate to another fabric topology.
• Deploy multiple independent SANs.
Nondisruptive migration
If you have a level 4 multiple fabric NSPOF SAN, you can fail over all operations to one fabric and
then reconfigure the other fabric.
When planning a migration, try to avoid or minimize the movement of devices between switches.
Migrations that require the addition or re-cabling of ISLs are less disruptive than migrations that require
movement of device connections.
Migrating a cascaded fabric SAN
This section describes migration paths for a cascaded fabric SAN.
Cascaded to meshed
To create a meshed fabric SAN, you need additional ISLs to connect all switches. To ensure a successful
migration, calculate the number of ports needed for the additional ISLs. You may need to move device
connections to another switch to make ports available for ISLs.
Cascaded to ring
If you have a linear cascaded fabric SAN, connect the last switch in the fabric to the first switch to
create a ring fabric SAN. If you have a tree-like cascaded fabric SAN (with multiple levels), you may
need to re-cable the ISLs.
Cascaded to core-edge
Determine which switches will be the backbone switches and which ones will be the edge switches.
Re-cable the ISLs to connect all edge switches to the core switches. Connect devices (servers and
storage) or core switches, as required. This migration is less disruptive if you use the existing switches
as edge switches and add switches as core switches.
Migrating a meshed fabric SAN
This section describes migration paths for a meshed fabric SAN.
Meshed to ring
You can migrate a meshed fabric SAN to a ring fabric SAN by removing the cross-connected ISLs
and leaving the outer-connected ISLs as a ring. Use the available ports for device connections or for
redundant ring ISL connections.
SAN fabric topologies 58