However,
if
one
of
the
ESMs
fails,
the
surviving
ESM
manages
I/Os
to
all
of
the
drives
in
the
EXP100
chassis,
as
shown
in
1
2
3
4
5
6
7
8
9
10
11
12
13
14
left ESM
FC OUT
FC IN
From
controller
drive port or
FC port in
another
EXP100
From
controller
drive port or
FC port in
another
EXP100
To controller
drive port or
FC port in
another
EXP100
To controller
drive port or
FC port in
another
EXP100
Port Bypass Logic
FibreChannel-SATA
Bridge
FC OUT
FC IN
FibreChannel-SATA
Bridge
right ESM
Internal ESM --
ESM link
Port Bypass Logic
exp12cfg8
Figure
10.
The
right
ESM
and
controller
firmware
recover
from
a
loss
of
connectivity
to
the
input
port
of
the
left
ESM
26
IBM
TotalStorage
DS4000
EXP100
Storage
Expansion
Enclosure:
Installation,
User’s
and
Maintenance
Guide
Summary of Contents for TotalStorage EXP100
Page 2: ......
Page 187: ......
Page 188: ... Part Number 39M5947 Printed in USA GC26 7694 01 1P P N 39M5947 ...
