IBM System Storage DS3500 Introduction And Implementation Manual page 90

7914DS3KPlanning_090710.fm
Storage partitioning considerations
By default an "access" logical drive is created mapped to each partition created. If in-band
management is being used, then the access logical drive must be mapped to the storage
partition for the managing host. For all others this logical drive can be removed.
In a security-sensitive environment, you can assign a password to the storage system as well.
Note: Each host with separately assigned storage will use a storage partition. Each host
group with separately assigned storage to be shared by the group will also use a storage
partition.
In order to configure the storage partitioning correctly, you need the WWN of your host HBAs.
Mapping is done on a WWN basis. Depending on your HBA, you can obtain the WWN either
from the BIOS or QLogic SANsurfer tool if you have QLogic cards. Emulex adapters and IBM
adapters for IBM System p and IBM System i® servers have a sticker on the back of the card.
The WWN is also usually printed on the adapter itself or the box that the adapter was shipped
in.
If you are connected to a hub or switch, check the Name Server Table of the hub or switch to
identify the WWN of the HBAs.
When planning your partitioning, keep in mind that:
By default the DS3500 comes with four partitions
In a cluster environment, you need to use host groups.
You can optionally purchase additional partitions (maximum of 64).
When planning for your storage partitioning, create a table of planned partitions and groups
so that you can clearly map out and define your environment.
Best practice: If you have a single server in a host group that has one or more LUNs
assigned to it, do the mapping to the host and not the host group. All servers with the same
host type (for example, Windows servers) can be in the same group if you want, but by
mapping the storage at the host level, you can define what specific server accesses which
specific logical drives.
However, if you have a host cluster, you will need to assign the shared logical drives at a
host group level, so that all of the host servers in that host group have access to these
logical drives for host cluster failover to work. This practice is also used when creating a
partition for shared filesystem servers (GPFS™ for example).
Table 3-5 shows an example of a storage partitioning plan, which clearly shows the host
groups, hosts, port names, WWN of the ports, and the operating systems used in that
environment. Other columns can be added to the table for future references, such as HBA
BIOS levels, driver revisions, and switch ports used, all of which can then form the basis of a
change control log.
Table 3-5 Sample plan for storage partitioning
Host group
Windows 2003
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IBM System Storage DS3500: Introduction and Implementation Guide
Host name Port name
Windows Host MailAdp_A
MailAdp_B
Draft Document for Review March 28, 2011 12:24 pm
WWN
200000E08B28773C
200000E08B08773C
OS type
Windows 2003
Non-Clustered