IBM TotalStorage DS6000 Series - Manual (Page 56)

32 DS6000 Series: Concepts and Architecture
Figure 2-10 Switched disk expansion
DDMs
Each DDM is hot plugable and has two indicators. The green indicator shows disk activity
while the amber indicator is used with light path diagnostics to allow the customer to identify
and replace a failed DDM.
At present, the DS6000 allows the choice of four different DDM types:
73 GB, 15K RPM drive
146 GB, 10K RPM drive
146 GB, 15K RPM drive
300 GB, 10K RPM drive
All DDMs exist in what are called array sites. Array sites containing four DDMs are created as
DDMs are installed. During configuration discussed in Chapter 10, “DS CLI” on page 195, you
have the choice of creating a RAID-5 or RAID-10 array by choosing one or two array sites.
The first and the third array sites created on each loop each contribute one DDM to be a
1
16 FC switch FC switch
16
1 FC
switch
FC
s
w
itch
Controller 0
16
1 FC switch FC switch
1
16 FC switch FC switch
Controller 1
First
expansion
enclosure
Up to 16 DDMs
per enclosure
Third
expansion
enclosure
OUT ports to next enclosure
OUT ports to next enclosure
Cables between
enclosures
Fibre channel
switches
Server
enclosure
Second
expansion
enclosure
Loop
1
Four en
clo
sure
s
ma
xi
mu
m p
er
lo
op
L
oop 0
Four en
clo
sure
s
ma
xi
mu
m per
loo
p
Internal
connections
through
midplane
Raid controller
DISK CONTRL
ports
Raid controller
DISK EXP ports