7065Admin_Configure.fm
Draft Document for Review August 30, 2007 12:59 am
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IBM System Storage DS3000: Introduction and Implementation Guide
8.1 Configure host access
Host access is how a host (server) can access storage on the DS3000.
8.1.1 What is a host?
First, we will take a closer look at configuring hosts. Hosts in a DS3000 context can have a
number of meanings:
Host Port:
A Host Port is a single Host Bus Adapter Port in a server which is attached to the storage
subsystem. The Port can be a Port on a SAS, iSCSI or FC Host Bus Adapter (HBA),
depending on the technology used. Each port uses a unique identifier known as the World
Wide Name (WWN). If you are using dual port adapters, they have of course two WWNs -
one for each port. iSCSI software initiators also generate a WWN for identification.
Hosts
A host is a single system that can be mapped to a logical drive. The DS3000 only
communicates through the use of a WWN. The DS3000 is not by default aware of which
HBAs are in the same server or of servers that have a certain relationship, such as a
cluster. This is something you have to configure on your storage server. You can create
hosts and assign to them one or several WWN of the host ports.
Host groups:
A host group is a collection of hosts, that are allowed to access certain logical drives, for
example, a cluster of two systems.
To summarize, every HBA port in a server has its own unique WWN. This WWN can be
assigned to create single hosts. If several hosts have to access the same logical drive you
can use host groups to achieve that.
8.1.2 Preparations on the host server
Before start to configure your storage subsystem you should do some preparation on the host
server and your environment to make the configuration simpler.
Install the host HBAs in the host server - see your server’s documentation for any special
instructions. Some servers have recommended slots to use for installing an HBA. For
redundancy, we always recommend to use two HBAs per host. Update the HBA firmware
and the host server firmware to the current levels and shut down your host server.
Attach all host cabling to the storage subsystem.
If you are not using a direct attached topology, configure your switches to ensure the right
zoning. We show some sample zoning configurations in Chapter 19, “FC configuration 1 -
Emulex HBA boot BladeServer from SAN” on page 441 and Chapter 21, “FC configuration
3 - Linux SAN boot with System x 3755” on page 493.For DS3400 you can use QLogic or
Emulex HBAs. Power on your server and enter the HBAs BIOS setup. This is done by
entering a particular key sequence while the BIOS is loading. If you do not see the BIOS
loading during the bootup sequence, make sure that ROM Control Execution is Enabled
on your host server.
Note: IBM server firmware can be found on the IBM Support homepage:
http://www-304.ibm.com/jct01004c/systems/support/
