On Setting Up Ports; Distances Supported For Fibre Channel Type, Number Of Switches - HP StorageWorks P9000 User Manual

3. The data transfer speed of your Continuous Access Journal ports must be greater than peak
write-IOPS.
Using peak IOPS and the IOPS threshold of your systems' port microprocessors, calculate the
number of microprocessors (and Fibre Channel ports) the Continuous Access Journal system
requires.
For example: if your performance monitoring software shows peak IOPS at 10,000, and if
factory specifications show that microprocessors have a threshold of 7,000 IOPS, then the
Continuous Access Journal system would require another port.
The following shows the calculation:
Peak IOPS / IOPS threshold = Number of microprocessors required (
x 2 = number of Fibre Channel ports required)

On setting up ports

The following tips are provided to help you design your port configuration:
When new data exists, the initiator port on the local system sends informational commands
to the secondary RCU target port.
The remote system initiator port sends journal query commands to the local RCU target port.
When new data exists in the primary system, the data is sent through these ports — that is,
from primary side RCU target port(s) to secondary system initiator port(s).
An example configuration could consist of the following:
Two initiator ports on the local side, with two matching RCU target ports on the remote
◦
side
Four initiator ports on the remote side, with four matching RCU target ports on the local
◦
side.
An initiator port on one side must have an RCU target port on the other side.
If your system will support a disaster recovery failover/failback environment, initiator and
RCU target ports should be sized equivalently on primary and secondary systems.
Up to eight paths can be established in both directions. HP strongly recommends that you
establish at least two independent data paths to provide hardware redundancy.
Host paths cannot be connected to an initiator port. However, they can be attached to RCU
target ports.
NOTE: Two or more initiator ports must be configured before you can add the secondary storage
systems and create the Continuous Access Journal volume pairs.

Distances supported for Fibre Channel type, number of switches

Fibre Channel multimode or single-mode optical fiber cables are required on primary and secondary
systems. The type of cable and number of switches depends on the distance between primary and
secondary sites.
0 to 0.5 km: multimode optical shortwave fiber cables are required.
0.5 km to 1.5 km (1,640 to 4,920 feet): multimode shortwave Fibre Channel interface cables
are required; one switch is required, two maximum.
1.5 km to 10 km: single optical long wave fiber cables are required.
10 km to 30 km (6.2 to 18.6 miles): single-mode long wave Fibre Channel interface cables
are required; one switch is required, two maximum.
Greater than 30 km (18.6 miles): approved third-party channel extender products and
telecommunications lines are required.
40 Planning the data path