IBM System storage DS6000 Series, Красные книги

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DS6000 Series: Concepts and Architecture
Figure 9-4 Example of Volume Group, LUNs and host attachment definition
In Figure 9-4 we show three hosts (Host A, Host B, and Host C). The three hosts are
defined in the logical configuration as three different
host systems
. The user will group the
WWPN of each host system in groups called host attachments. As shown in the diagram,
each host attachment is assigned to one volume group. Volumes can belong to several
volume groups. For example, volumes 5 and 6 are in Volume Group 2 and Volume Group
3, so they will be shared by Host A, Host B and Host C. Several host attachments can be
associated to the same volume group. For example, Hosts B and C will share volumes 5,
6, 7 and 8 because their host attachments are assigned to Volume Group 3. However, for
management simplification, we recommend that only one host attachment is assigned to
each volume group.
򐂰 The maximum number of volume groups for the DS6000 is 1040.
Address groups
An address group is a group of FB or CKD LSSs. An address group has up to 16 LSSs. The
DS6000 supports two address groups: address group 0 and address group 1.
LSS/LCU
A Logical Subsystem (LSS) is a topological construct that consists of a group of up to 256
logical volumes. A DS6000 can have up to 32 LSSs. The DS6000 supports a mix of
CKD-formatted logical subsystems and FB logical subsystems. There is a one-to-one
mapping between a CKD logical subsystem and a zSeries control unit.
For zSeries hosts, a logical subsystem represents a logical control unit (LCU). Each control
unit is associated with only one logical subsystem.
Host System A
2
Host Attachment
WWPN WWPN
Host Attachment
WWPN
WWPN
Host System B
1
3
5
4
6
8
7
Volume Group 1
Volume Group 2 Volume Group 3
Host Attachment
WWPN WWPN
Host System C
Host Attachment
WWPN WWPN
It is possible to have
several Host Attachments
associated to one Volume
Group.
But we do recommend,
for management
to associate only one Host
attachment to each Volume
Group