IBM System Storage DS4000, Руководство по оборудованию

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IBM Midrange System Storage Hardware Guide
By understanding your data and applications, you can also better understand growth
patterns. Being able to estimate an expected growth is vital for the capacity planning of your
DS5000 storage subsystem installation. Clearly indicate the expected growth in the planning
documents: The actual patterns might differ from the plan according to the dynamics of your
environment.
Selecting the right DS5000 storage subsystem model for your current and perceived future
needs is one of the most crucial decisions you will make. The good side, however, is that the
DS5000 offers scalability and expansion flexibility. Premium features can be purchased and
installed at a later time to add functionality to the storage subsystem.
In any case, it is perhaps better to purchase a higher model than one strictly dictated by your
current requirements and expectations. This will allow for greater performance and scalability
as your needs and data grow.
SAN zoning
Zoning is an important part of integrating a DS5000 storage subsystem into a SAN. When
done correctly, it can eliminate many common problems.
Depending on your host operating system and the device driver you are planning to use, you
have to zone your SAN differently. In AIX or Solaris using old RDAC, only one path per
controller is supported, so you have to create a zone for the connection between the host bus
adapter (HBA1) and controller A and a separate zone that contains the other HBA2 to
controller B.
If using a multipath driver as MPIO, or MPP in Linux, then you can connect and zone your
SAN to have multiple paths to the same controller, and then create additional zones for
access to other resources. This isolates each zone down to its simplest form.
Enhanced Remote Mirroring considerations
When using Enhanced Remote Mirroring (ERM), you must create two additional zones:
򐂰 The first zone contains the ERM source DS5000 controller A and ERM target DS5000
controller A.
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The second zone contains the ERM source DS5000 controller B and ERM target DS5000
controller B.
4.3.2 Planning for iSCSI attachment
In addition to using Fibre Channel as the interface connection method, iSCSI host interfaces
allows servers with specialized hardware iSCSI cards, or with software running over regular
Ethernet cards, run the iSCSI protocol as the connection method to attach the DS5000
storage subsystems. As with FC, before beginning an iSCSI deployment, plan in advance and
understand and document the network topology that will be used.
Best practices:
򐂰 Connect your storage and create zones by considering the number of paths allowed to
the same controller by your host operative system multipath driver.
򐂰 Make sure to have only one initiator per zone.
򐂰
Disk and tape should be on separate HBAs, which follows the best practice for zoning.