
extra
bytes.
The
storage
unit
LIC
uses
the
sequence
number
and
LRC.
The
storage
unit
does
not
transfer
them
to
the
host
system.
Most
fixed-block
disk
architectures
use
a
fixed-byte
sector
of
512-bytes.
This
includes
most
UNIX
systems,
including
AIX.
When
used
in
a
storage
unit,
the
format
of
a
DDM
has
a
fixed–byte
sector
of
524-bytes.
The
524-byte
sector
format
enables
the
storage
unit
to
connect
to
a
wide
range
of
host
systems
and
share
data
between
them.
The
524-byte
sector
on
the
DDM
is
independent
of
the
sector
size
exposed
to
the
host
for
a
given
device
type
emulation.
Most
LUNs
for
open-systems
hosts
are
exposed
with
a
512-byte
sector.
System
i
host
systems
use
eight
bytes
at
the
start
of
the
sector.
UNIX
host
systems
do
not
use
these
eight
bytes
when
you
attach
them
to
the
storage
unit.
The
data
portion
of
the
sector
remains
at
512-bytes
for
all
host
systems.
A
2-byte
sequence
number
and
a
2-byte
LRC
increase
the
size
of
the
sector
to
524-bytes.
Overview
of
the
logical
volume
management
software
The
logical
volume
manager
(LVM)
software
migrates
data
at
a
single
logical
volume
level,
a
physical
volume
(DDM)
level,
or
entire
contents
of
a
volume
group.
The
LVM
software
provides
complete
control
over
all
disks
and
file
systems.
The
primary
tasks
involved
in
migrating
data
using
the
LVM
rely
upon
the
use
of
LVM
commands
that
affect
the
following
functions:
v
Copying
v
Mirroring
v
Migrating
Direct
copy
is
another
method
to
migrate
data.
While
this
method
uses
LVM,
its
main
focus
is
on
the
use
of
the
UNIX
®
find
command
and
the
cpio
command.
Copying
a
complete
logical
volume
Use
this
information
as
a
guide
for
using
the
logical
volume
manager
(LVM)
cplv
command
to
copy
a
complete
logical
volume.
The
AIX
LVM
provides
the
cplv
command
for
copying
logical
volumes
within
volume
groups
or
to
different
volume
groups.
You
can
use
this
command
to
create
a
new
logical
volume
while
running
the
command,
or
you
can
overwrite
an
existing
logical
volume.
The
following
two
examples
shows
how
to
use
the
cplv
command.
#
cplv
-v
datavg
-y
newlv
oldlv
#
cplv
-e
existinglv
oldlv
In
the
first
example,
the
cplv
command
copies
data
from
the
existing
logical
volume
oldlv
.
It
creates
a
new
logical
volume
that
it
calls
newlv
(-y)
in
the
volume
group
datavg
(-v)
.
If
you
omit
the
-v
option,
the
volume
group
to
which
the
existing
logical
volume
belongs
receives
the
new
logical
volume.
When
the
cplv
command
creates
a
new
logical
volume,
it
creates
the
new
volume
with
exactly
the
same
characteristics
as
the
existing
logical
volume.
Chapter
9.
Migrating
data
to
a
storage
unit
143
Содержание DS8000 - ADDITIONAL INFORMATION
Страница 1: ...IBM System Storage DS8000 User s Guide V ersion 1 Release 4 SC26 7915 02 ...
Страница 2: ......
Страница 3: ...IBM System Storage DS8000 User s Guide V ersion 1 Release 4 SC26 7915 02 ...
Страница 8: ...vi DS8000 User s Guide ...
Страница 10: ...viii DS8000 User s Guide ...
Страница 12: ...x DS8000 User s Guide ...
Страница 14: ...xii DS8000 User s Guide ...
Страница 26: ...xxiv DS8000 User s Guide ...
Страница 106: ...78 DS8000 User s Guide ...
Страница 168: ...140 DS8000 User s Guide ...
Страница 202: ...174 DS8000 User s Guide ...
Страница 204: ...176 DS8000 User s Guide ...
Страница 212: ...184 DS8000 User s Guide ...
Страница 242: ...214 DS8000 User s Guide ...
Страница 246: ...218 DS8000 User s Guide ...
Страница 249: ......
Страница 250: ... Printed in USA SC26 7915 02 ...