<s>
EXOFS	B-Application
(	O
formerly	O
known	O
as	O
OSDFS	O
)	O
is	O
an	O
object-based	B-Application
file	I-Application
system	I-Application
implemented	O
on	O
top	O
of	O
an	O
external	O
object	O
store	O
.	O
</s>
<s>
and	O
object	B-Application
storage	I-Application
devices	I-Application
.	O
</s>
<s>
Exofs	B-Application
was	O
originally	O
developed	O
by	O
Avishay	O
Traeger	O
for	O
IBM	O
HRL	O
and	O
was	O
originally	O
based	O
on	O
the	O
ext2	B-Application
file	B-Application
system	I-Application
.	O
</s>
<s>
Since	O
2008	O
,	O
Panasas	O
develops	O
and	O
maintains	O
Exofs	B-Application
on	O
.	O
</s>
<s>
Exofs	B-Application
has	O
been	O
included	O
in	O
the	O
mainline	O
Linux	B-Operating_System
kernel	I-Operating_System
since	O
version	O
2.6.30-rc1	O
,	O
but	O
no	O
Linux	B-Operating_System
distribution	O
implemented	O
this	O
with	O
a	O
utility	O
for	O
making	O
file	B-Application
systems	I-Application
in	O
exofs	B-Application
for	O
the	O
current	O
kernel	B-Operating_System
line	O
.	O
</s>
