HP StorageWorks Scalable File Share System Installation and Upgrade Guide Version 2.2

Configuring the storage5–6
• HP recommends that you make your OST LUNs as large as possible. However, as
explained in Section 5.1.2, if a service LUN or an MDS LUN already exists in a disk group,
the OST LUNs must be sized so that the total used size is 90% of the total capacity of the
disk group.
Role
The role of the LUN is one of the following:
• adm — the administration LUN
• service — a service LUN
• mds — an MDS LUN
• ost — an OST LUN
LUN roles are described in Section 5.1.3.1.
Presented to
Specifies the servers the LUN is to be presented to.
5.1.3.2.1 EVA4000 configuration example 1 — minimal system
Table 5-1 shows how to configure LUNs in a system comprised of two servers and two EVA4000 arrays. In
this configuration, you can create a file system comprised of one MDS service and four OST services.
Table 5-1 Minimal system example
Array Disk Group Size Role Presented to Notes
1 140GB
1
1. Can be configured to a different size.
adm south[1-2] The administration LUN.
21GBservice south[1-2] The service LUN for south1 and south2.
1Size can
vary
mds south[1-2] An MDS LUN. See Section 5.5 for information
on sizing the MDS LUN.
2Size can
vary
mds south[1-2] The second of the pair of LUNs for the MDS
service.
1 Uses
remaining
capacity
(90% rule)
ost south[1-2] The first OST LUN. The size is the space
remaining (out of 90% of actual capacity)
after administration and MDS LUNs have been
created, and allowance has been made for
redundancy overheads.
2 Uses
remaining
capacity
(90% rule)
ost south[1-2] The second OST LUN. The size is the space
remaining (out of 90% of actual capacity)
after the service and MDS LUNs have been
created, and allowance has been made for
redundancy overheads.
2 1 Uses 90%
capacity
ost south[1-2] The third OST LUN. You must leave 10% of
actual capacity unused, and allow for
redundancy overheads.
2 Uses 90%
capacity
ost south[1-2] The fourth OST LUN. You must leave 10% of
actual capacity unused, and allow for
redundancy overheads.