<s>
VMware	B-Application
VMFS	I-Application
(	O
Virtual	B-Application
Machine	I-Application
File	I-Application
System	I-Application
)	O
is	O
VMware	O
,	O
Inc.	O
'	O
s	O
clustered	B-Application
file	I-Application
system	I-Application
used	O
by	O
the	O
company	O
's	O
flagship	O
server	O
virtualization	O
suite	O
,	O
vSphere	O
.	O
</s>
<s>
VMFS	B-Application
volumes	O
can	O
be	O
logically	O
"	O
grown	O
"	O
(	O
non-destructively	O
increased	O
in	O
size	O
)	O
by	O
spanning	O
multiple	O
VMFS	B-Application
volumes	O
together	O
.	O
</s>
<s>
There	O
are	O
six	O
(	O
plus	O
one	O
for	O
vSAN	O
)	O
versions	O
of	O
VMFS	B-Application
,	O
corresponding	O
with	O
ESX/ESXi	O
Server	O
product	O
releases	O
.	O
</s>
<s>
VMFS0	O
can	O
be	O
reported	O
by	O
ESX	B-Operating_System
Server	I-Operating_System
v6.5	O
as	O
a	O
VMFS	B-Application
version	O
when	O
a	O
datastore	O
is	O
unmounted	O
from	O
a	O
cluster/host	O
.	O
</s>
<s>
VMFS1	O
was	O
used	O
by	O
ESX	B-Operating_System
Server	I-Operating_System
v1.x	O
.	O
</s>
<s>
VMFS2	B-Application
is	O
used	O
by	O
ESX	B-Operating_System
Server	I-Operating_System
v2.x	O
and	O
(	O
in	O
a	O
limited	O
capacity	O
)	O
v3.x	O
.	O
</s>
<s>
VMFS2	B-Application
is	O
a	O
flat	O
filesystem	O
with	O
no	O
directory	O
structure	O
.	O
</s>
<s>
VMFS3	B-Application
is	O
used	O
by	O
ESX	B-Operating_System
Server	I-Operating_System
v3.x	O
and	O
vSphere	O
4.x	O
.	O
</s>
<s>
VMFS-L	O
is	O
the	O
underlying	O
file	O
system	O
for	O
VSAN-1.0	O
.	O
</s>
<s>
Leaf	O
level	O
VSAN	O
objects	O
reside	O
directly	O
on	O
VMFS-L	O
volumes	O
that	O
are	O
composed	O
from	O
server	O
side	O
direct	O
attached	O
storage	O
(	O
DAS	O
)	O
.	O
</s>
<s>
Allows	O
access	O
by	O
multiple	O
ESXi	B-Operating_System
servers	O
at	O
the	O
same	O
time	O
by	O
implementing	O
per-file	O
locking	O
.	O
</s>
<s>
Add	O
or	O
delete	O
an	O
ESXi	B-Operating_System
server	O
from	O
a	O
VMware	B-Application
VMFS	I-Application
volume	O
without	O
disrupting	O
other	O
ESXi	B-Operating_System
servers	O
.	O
</s>
<s>
With	O
ESX/ESXi4	O
,	O
VMFS	B-Application
volumes	O
can	O
also	O
be	O
expanded	O
using	O
LUN	O
expansion	O
.	O
</s>
<s>
While	O
present	O
in	O
previous	O
versions	O
automatic	O
unmap	O
was	O
added	O
to	O
VMFS	B-Application
6	O
allowing	O
for	O
automatic	O
space	O
reclamation	O
requests	O
which	O
previously	O
were	O
manually	O
actioned	O
.	O
</s>
<s>
Can	O
be	O
shared	O
with	O
up	O
to	O
64	O
ESXi	B-Operating_System
Servers	O
.	O
</s>
<s>
Maximum	O
filesystem	O
size	O
is	O
50	O
TB	O
as	O
of	O
VMFS3	B-Application
,	O
and	O
62	O
TB	O
as	O
of	O
VMFS5	O
.	O
</s>
<s>
Maximum	O
LUN	O
size	O
of	O
2	O
TB	O
as	O
of	O
VMFS3	B-Application
and	O
64	O
TB	O
as	O
of	O
VMFS5	O
.	O
</s>
<s>
In	O
VMFS3	B-Application
and	O
VMFS5	O
prior	O
to	O
vSphere	O
5.1	O
,	O
the	O
maximum	O
number	O
of	O
hosts	O
which	O
can	O
share	O
a	O
read-only	O
file	O
is	O
8	O
.	O
</s>
<s>
VMFS3	B-Application
limits	O
files	O
to	O
262,144	O
(	O
218	O
)	O
blocks	O
,	O
which	O
translates	O
to	O
256	O
GB	O
for	O
1	O
MB	O
block	O
sizes	O
(	O
the	O
default	O
)	O
up	O
to	O
2	O
TB	O
for	O
8	O
MB	O
block	O
sizes	O
.	O
</s>
<s>
VMFS5	O
uses	O
1	O
MB	O
blocks	O
throughout	O
(	O
with	O
block	B-Application
suballocation	I-Application
for	O
small	O
files	O
)	O
,	O
and	O
has	O
a	O
file	O
size	O
limit	O
of	O
62	O
TB	O
,	O
though	O
the	O
VMDK	O
size	O
is	O
restricted	O
to	O
2	O
TB	O
-	O
512	O
B	O
in	O
ESXi	B-Operating_System
versions	O
earlier	O
than	O
5.5	O
due	O
to	O
a	O
limitation	O
in	O
the	O
version	O
of	O
SCSI	O
emulated	O
.	O
</s>
<s>
There	O
is	O
also	O
a	O
limit	O
of	O
approx	O
30,720	O
files	O
(	O
using	O
MBR	B-Device
)	O
on	O
a	O
single	O
VMFS3	B-Application
datastore	O
.	O
</s>
<s>
A	O
Java	B-Language
open	O
source	O
VMFS	B-Application
driver	O
enables	O
read-only	O
access	O
to	O
files	O
and	O
folders	O
on	O
partitions	O
formatted	O
with	O
the	O
Virtual	B-Application
Machine	I-Application
File	I-Application
System	I-Application
(	O
VMFS	B-Application
)	O
is	O
developed	O
and	O
maintained	O
by	O
AG	O
.	O
</s>
<s>
It	O
allows	O
features	O
like	O
offloaded	O
backups	O
of	O
virtual	O
machines	O
hosted	O
on	O
VMware	B-Operating_System
ESXi	I-Operating_System
hosts	O
up	O
to	O
VMFSv3	O
.	O
</s>
<s>
vmfs-tools	O
supports	O
more	O
VMFS	B-Application
features	O
and	O
read	O
only	O
VMFS	B-Application
mounts	O
through	O
the	O
standard	O
Linux	B-Application
VFS	B-Application
and	O
the	O
FUSE	B-Application
framework	O
.	O
</s>
<s>
Developed	O
by	O
Christophe	O
Fillot	O
and	O
Mike	O
Hommey	O
and	O
available	O
as	O
source	O
code	O
download	O
at	O
the	O
or	O
the	O
Debian	O
and	O
Ubuntu	B-Operating_System
packages	B-Application
.	O
</s>
