<s>
LizardFS	B-Application
is	O
an	O
open	B-Application
source	I-Application
distributed	B-Protocol
file	I-Protocol
system	I-Protocol
that	O
is	O
POSIX-compliant	O
and	O
licensed	O
under	O
GPLv3	O
.	O
</s>
<s>
It	O
was	O
released	O
in	O
2013	O
as	O
fork	O
of	O
MooseFS	B-Application
.	O
</s>
<s>
LizardFS	B-Application
is	O
also	O
offering	O
a	O
paid	O
Technical	O
Support	O
(	O
Standard	O
,	O
Enterprise	O
and	O
Enterprise	O
Plus	O
)	O
with	O
possibility	O
of	O
configurating	O
and	O
setting	O
up	O
the	O
cluster	O
and	O
active	O
cluster	O
monitoring	O
.	O
</s>
<s>
LizardFS	B-Application
is	O
a	O
distributed	O
,	O
scalable	O
and	O
fault-tolerant	O
file	O
system	O
.	O
</s>
<s>
LizardFS	B-Application
makes	O
files	O
secure	O
by	O
keeping	O
all	O
the	O
data	O
in	O
multiple	O
replicas	B-Architecture
spread	O
over	O
the	O
available	O
servers	O
.	O
</s>
<s>
It	O
can	O
also	O
be	O
used	O
to	O
build	O
space-efficient	O
storage	O
because	O
it	O
is	O
designed	O
to	O
run	O
on	O
commodity	B-Device
hardware	I-Device
.	O
</s>
<s>
LizardFS	B-Application
is	O
fully	O
hardware	O
agnostic	O
.	O
</s>
<s>
Commodity	B-Device
hardware	I-Device
can	O
be	O
utilized	O
for	O
cost	O
efficiency	O
.	O
</s>
<s>
The	O
minimum	O
requirements	O
are	O
two	O
dedicated	O
nodes	O
with	O
a	O
number	O
of	O
disks	O
,	O
but	O
to	O
obtain	O
a	O
high	B-General_Concept
available	I-General_Concept
installation	O
at	O
least	O
3	O
nodes	O
are	O
needed	O
.	O
</s>
<s>
LizardFS	B-Application
keeps	O
metadata	O
(	O
e.g.	O
</s>
<s>
A	O
suggested	O
configuration	O
of	O
a	O
metadata	O
server	O
is	O
a	O
machine	O
with	O
fast	O
CPU	B-Device
,	O
at	O
least	O
32	O
GB	O
of	O
RAM	O
and	O
at	O
least	O
one	O
drive	O
(	O
preferably	O
SSD	O
)	O
to	O
store	O
several	O
GB	O
of	O
metadata	O
.	O
</s>
<s>
A	O
suggested	O
configuration	O
of	O
a	O
chunkserver	O
is	O
a	O
machine	O
with	O
large	O
disk	O
space	O
available	O
either	O
in	O
a	O
JBOD	O
or	O
RAID	B-Architecture
configuration	O
.	O
</s>
<s>
CPU	B-Device
and	O
RAM	O
are	O
not	O
very	O
important	O
.	O
</s>
<s>
Clients	O
who	O
use	O
the	O
data	O
stored	O
on	O
LizardFS	B-Application
.	O
</s>
<s>
These	O
machines	O
use	O
LizardFS	B-Application
mount	O
to	O
access	O
files	O
in	O
the	O
installation	O
and	O
process	O
them	O
just	O
like	O
those	O
on	O
their	O
local	O
hard	O
drives	O
.	O
</s>
<s>
Files	O
stored	O
on	O
LizardFS	B-Application
can	O
be	O
seen	O
and	O
accessed	O
by	O
as	O
many	O
clients	O
as	O
needed	O
.	O
</s>
<s>
Snapshots	B-Application
-	O
When	O
creating	O
a	O
snapshot	B-Application
,	O
only	O
the	O
metadata	O
of	O
a	O
target	O
file	O
is	O
copied	O
,	O
speeding	O
up	O
the	O
operation	O
.	O
</s>
<s>
QoS	O
-	O
LizardFS	B-Application
offers	O
mechanisms	O
that	O
allow	O
administrators	O
to	O
set	O
read/write	O
bandwidth	O
limits	O
for	O
all	O
the	O
traffic	O
generated	O
by	O
a	O
given	O
mount	O
point	O
,	O
as	O
well	O
as	O
for	O
a	O
specific	O
group	O
of	O
processes	O
spread	O
over	O
multiple	O
client	O
machines	O
and	O
mountpoints	O
.	O
</s>
<s>
Data	B-Architecture
replication	I-Architecture
-	O
Files	O
stored	O
in	O
LizardFS	B-Application
are	O
divided	O
into	O
blocks	O
called	O
chunks	O
,	O
each	O
up	O
to	O
64	O
MB	O
in	O
size	O
.	O
</s>
<s>
For	O
example	O
,	O
choosing	O
to	O
keep	O
3	O
copies	O
(	O
configuration	O
goal	O
=3	O
)	O
,	O
all	O
of	O
the	O
data	O
will	O
survive	O
a	O
failure	O
of	O
any	O
two	O
disks	O
or	O
chunkservers	O
,	O
because	O
LizardFS	B-Application
will	O
never	O
keep	O
2	O
copies	O
of	O
the	O
same	O
chunk	O
on	O
the	O
same	O
node	O
.	O
</s>
<s>
Geo-replication	B-General_Concept
-	O
With	O
Geo-replication	B-General_Concept
you	O
can	O
decide	O
where	O
the	O
chunks	O
are	O
stored	O
.	O
</s>
<s>
For	O
example	O
,	O
when	O
LizardFS	B-Application
is	O
deployed	O
across	O
two	O
data	O
centers	O
,	O
e.g.	O
</s>
<s>
Metadata	O
replication	B-Architecture
-	O
Metadata	O
is	O
stored	O
on	O
metadata	O
servers	O
.	O
</s>
<s>
High	B-General_Concept
availability	I-General_Concept
-	O
Shadow	O
master	O
servers	O
provide	O
LizardFS	B-Application
with	O
High	B-General_Concept
Availability	I-General_Concept
.	O
</s>
<s>
Quotas	B-Application
-	O
LizardFS	B-Application
support	O
disk	B-Application
quota	I-Application
mechanism	O
known	O
from	O
other	O
POSIX	O
le	O
systems	O
.	O
</s>
<s>
A	O
user	O
whose	O
hard	O
limit	O
is	O
exceeded	O
cannot	O
write	O
new	O
data	O
to	O
LizardFS	B-Application
.	O
</s>
<s>
Trash	O
-	O
Another	O
feature	O
of	O
LizardFS	B-Application
is	O
a	O
transparent	O
and	O
fully	O
automatic	O
trash	O
bin	O
.	O
</s>
<s>
Native	O
Windows™	B-Application
client	O
-	O
LizardFS	B-Application
Windows	O
Client	O
can	O
be	O
installed	O
on	O
both	O
workstations	O
and	O
servers	O
.	O
</s>
<s>
It	O
provides	O
access	O
to	O
files	O
stored	O
on	O
LizardFS	B-Application
via	O
a	O
virtual	O
drive	O
.	O
</s>
<s>
The	O
Windows	O
client	O
is	O
a	O
licensed	O
feature	O
to	O
be	O
obtained	O
by	O
contacting	O
the	O
creators	O
of	O
LizardFS	B-Application
-	O
Distributed	O
FS	O
Sp	O
.	O
</s>
<s>
Monitoring	O
LizardFS	B-Application
offers	O
two	O
monitoring	O
interfaces	O
.	O
</s>
<s>
Hadoop	B-Application
-	O
This	O
is	O
a	O
java	O
based	O
solution	O
allowing	O
Hadoop	B-Application
to	O
use	O
LizardFS	B-Application
storage	O
,	O
implementing	O
an	O
HDFS	O
interface	O
to	O
LizardFS	B-Application
.	O
</s>
<s>
It	O
enables	O
you	O
to	O
use	O
Hadoop	B-Application
jobs	O
to	O
directly	O
access	O
the	O
data	O
on	O
a	O
LizardFS	B-Application
cluster	O
.	O
</s>
<s>
NFS	B-Protocol
and	O
pNFS	O
-	O
LizardFS	B-Application
uses	O
NFS-ganesha	O
server	O
to	O
create	O
NFS	B-Protocol
shares	O
,	O
so	O
technically	O
NFS	B-Protocol
client	O
connects	O
not	O
with	O
the	O
master	O
server	O
,	O
but	O
with	O
a	O
Ganesha	O
file	O
server	O
that	O
talks	O
directly	O
with	O
LizardFS	B-Application
components	O
.	O
</s>
<s>
From	O
the	O
user	O
point	O
of	O
view	O
,	O
it	O
works	O
just	O
like	O
an	O
ordinary	O
NFS	B-Protocol
server	O
.	O
</s>
