<s>
Vinum	O
is	O
a	O
logical	B-Application
volume	I-Application
manager	I-Application
,	O
also	O
called	O
software	O
RAID	B-Architecture
,	O
allowing	O
implementations	O
of	O
the	O
RAID-0	O
,	O
RAID-1	O
and	O
RAID-5	O
models	O
,	O
both	O
individually	O
and	O
in	O
combination	O
.	O
</s>
<s>
The	O
original	O
Vinum	O
was	O
part	O
of	O
the	O
base	O
distribution	O
of	O
the	O
FreeBSD	B-Operating_System
operating	O
system	O
since	O
3.0	O
,	O
and	O
also	O
NetBSD	B-Device
between	O
2003-10-10	O
and	O
2006-02-25	O
,	O
as	O
well	O
as	O
descendants	O
of	O
FreeBSD	B-Operating_System
,	O
including	O
DragonFly	B-Application
BSD	I-Application
;	O
in	O
more	O
recent	O
versions	O
of	O
FreeBSD	B-Operating_System
,	O
it	O
has	O
been	O
replaced	O
with	O
gvinum	O
,	O
which	O
was	O
first	O
introduced	O
around	O
FreeBSD	B-Operating_System
6	O
.	O
</s>
<s>
Vinum	O
source	O
code	O
is	O
maintained	O
in	O
the	O
FreeBSD	B-Operating_System
and	O
DragonFly	O
source	O
trees	O
.	O
</s>
<s>
Vinum	O
supports	O
RAID	B-Architecture
levels	O
0	O
,	O
1	O
,	O
5	O
,	O
and	O
JBOD	O
.	O
</s>
<s>
Vinum	O
was	O
inspired	O
by	O
Veritas	B-Application
Volume	I-Application
Manager	I-Application
.	O
</s>
<s>
Vinum	O
is	O
invoked	O
as	O
gvinum	O
(	O
GEOM	B-Application
Vinum	O
)	O
on	O
FreeBSD	B-Operating_System
version	O
5.4	O
and	O
up	O
.	O
</s>
<s>
In	O
modern	O
FreeBSD	B-Operating_System
,	O
it	O
may	O
be	O
considered	O
to	O
be	O
a	O
legacy	O
volume	B-Application
manager	I-Application
;	O
modern	O
alternatives	O
being	O
GEOM	B-Application
and	O
ZFS	B-Application
.	O
</s>
<s>
In	O
NetBSD	B-Device
,	O
it	O
has	O
been	O
removed	O
before	O
NetBSD	B-Device
4.0	O
due	O
to	O
lack	O
of	O
interest	O
and	O
maintenance	O
;	O
RAIDframe	O
was	O
cited	O
as	O
providing	O
similar	O
functionality	O
.	O
</s>
<s>
In	O
DragonFly	B-Application
BSD	I-Application
,	O
DragonFly	O
's	O
own	O
HAMMER	B-Application
filesystem	O
already	O
implements	O
network	O
mirroring	O
,	O
and	O
the	O
utility	O
could	O
be	O
used	O
to	O
configure	O
,	O
another	O
software	O
RAID	B-Architecture
implementation	O
,	O
which	O
originally	O
appeared	O
with	O
FreeBSD	B-Operating_System
6.0	O
as	O
,	O
but	O
was	O
deprecated	O
with	O
FreeBSD	B-Operating_System
9	O
,	O
and	O
removed	O
before	O
FreeBSD	B-Operating_System
10.0	O
;	O
and	O
a	O
NetBSD	B-Device
's	O
port	O
of	O
Red	O
Hat	O
's	O
lvm2	B-Application
is	O
also	O
available	O
in	O
the	O
base	O
system	O
of	O
DragonFly	O
as	O
well	O
all	O
in	O
addition	O
to	O
vinum	O
.	O
</s>
<s>
Additionally	O
,	O
there	O
are	O
hybrid	B-Architecture
RAIDs	I-Architecture
that	O
are	O
partly	O
software	O
-	O
and	O
partly	O
hardware-based	O
solutions	O
.	O
</s>
<s>
With	O
a	O
software	O
implementation	O
,	O
the	O
operating	O
system	O
manages	O
the	O
disks	O
of	O
the	O
array	O
through	O
the	O
normal	O
drive	O
controller	O
(	O
ATA	B-Protocol
,	O
SATA	O
,	O
SCSI	B-Architecture
,	O
Fibre	B-Architecture
Channel	I-Architecture
,	O
etc	O
.	O
)	O
.	O
</s>
<s>
With	O
present	O
CPU	B-General_Concept
speeds	O
,	O
software	O
RAID	B-Architecture
can	O
be	O
faster	O
than	O
hardware	O
RAID	B-Architecture
.	O
</s>
<s>
A	O
hardware	O
implementation	O
of	O
RAID	B-Architecture
requires	O
at	O
a	O
minimum	O
a	O
special-purpose	O
RAID	B-Architecture
controller	O
.	O
</s>
<s>
On	O
a	O
desktop	O
system	O
,	O
this	O
may	O
be	O
a	O
PCI	B-Protocol
expansion	O
card	O
,	O
or	O
might	O
be	O
a	O
capability	O
built	O
into	O
the	O
motherboard	O
.	O
</s>
<s>
In	O
larger	O
RAIDs	B-Architecture
,	O
the	O
controller	O
and	O
disks	O
are	O
usually	O
housed	O
in	O
an	O
external	O
multi-bay	O
enclosure	O
.	O
</s>
<s>
This	O
controller	O
handles	O
the	O
management	O
of	O
the	O
disks	O
,	O
and	O
performs	O
parity	O
calculations	O
(	O
needed	O
for	O
many	O
RAID	B-Architecture
levels	O
)	O
.	O
</s>
<s>
Hybrid	B-Architecture
RAIDs	I-Architecture
have	O
become	O
very	O
popular	O
with	O
the	O
introduction	O
of	O
inexpensive	O
hardware	O
RAID	B-Architecture
controllers	O
.	O
</s>
<s>
The	O
hardware	O
is	O
a	O
normal	O
disk	O
controller	O
that	O
has	O
no	O
RAID	B-Architecture
features	O
,	O
but	O
there	O
is	O
a	O
boot-time	O
application	O
that	O
allows	O
users	O
to	O
set	O
up	O
RAIDs	B-Architecture
that	O
are	O
controlled	O
via	O
the	O
BIOS	B-Operating_System
.	O
</s>
<s>
When	O
any	O
modern	O
operating	O
system	O
is	O
used	O
,	O
it	O
will	O
need	O
specialized	O
RAID	B-Architecture
drivers	O
that	O
will	O
make	O
the	O
array	O
look	O
like	O
a	O
single	O
block	O
device	O
.	O
</s>
<s>
Since	O
these	O
controllers	O
actually	O
do	O
all	O
calculations	O
in	O
software	O
,	O
not	O
hardware	O
,	O
they	O
are	O
often	O
called	O
"	O
fakeraids	B-Architecture
"	O
.	O
</s>
<s>
Unlike	O
software	O
RAID	B-Architecture
,	O
these	O
"	O
fakeraids	B-Architecture
"	O
typically	O
cannot	O
span	O
multiple	O
controllers	O
.	O
</s>
