<s>
Juju	B-Language
is	O
a	O
free	B-License
and	I-License
open	I-License
source	I-License
application	O
modeling	O
tool	O
developed	O
by	O
Canonical	O
Ltd	O
.	O
Juju	B-Language
is	O
an	O
application	O
management	O
system	O
.	O
</s>
<s>
It	O
was	O
built	O
to	O
reduce	O
the	O
operation	O
overhead	O
of	O
software	O
by	O
facilitating	O
,	O
deploying	O
,	O
configuring	O
,	O
scaling	O
,	O
integrating	O
,	O
and	O
performing	O
operational	O
tasks	O
on	O
public	O
and	O
private	O
cloud	O
services	O
along	O
with	O
bare-metal	B-General_Concept
servers	I-General_Concept
and	O
local	O
container-based	O
deployments	O
.	O
</s>
<s>
Juju	B-Language
aims	O
to	O
provide	O
a	O
modeling	O
language	O
that	O
abstracts	O
the	O
specifics	O
of	O
operating	O
complex	O
software	O
topologies	O
in	O
order	O
to	O
reduce	O
the	O
cost	O
of	O
operations	O
and	O
provide	O
flexibility	O
.	O
</s>
<s>
A	O
Juju	B-Language
model	O
is	O
an	O
environment	O
to	O
manage	O
and	O
operate	O
a	O
set	O
of	O
software	O
applications	O
.	O
</s>
<s>
A	O
Juju	B-Language
controller	O
is	O
the	O
service	O
that	O
tracks	O
the	O
events	O
,	O
state	O
,	O
and	O
user	O
activity	O
across	O
multiple	O
models	O
.	O
</s>
<s>
The	O
central	O
mechanism	O
behind	O
Juju	B-Language
is	O
called	O
charms	O
.	O
</s>
<s>
A	O
charm	O
is	O
a	O
collection	O
of	O
YAML	B-Protocol
configuration	O
files	O
and	O
a	O
selection	O
of	O
hooks	O
.	O
</s>
<s>
Juju	B-Language
has	O
two	O
components	O
:	O
a	O
client	O
and	O
a	O
bootstrap	O
node	O
.	O
</s>
<s>
Juju	B-Language
environments	O
can	O
be	O
bootstrapped	O
on	O
various	O
clouds	O
.	O
</s>
<s>
By	O
creating	O
a	O
Juju	B-Language
Provider	O
,	O
additional	O
cloud	O
environments	O
can	O
be	O
supported	O
.	O
</s>
<s>
Juju	B-Language
can	O
also	O
be	O
bootstrapped	O
on	O
bare-metal	B-General_Concept
servers	I-General_Concept
.	O
</s>
<s>
Small	O
deployments	O
can	O
use	O
the	O
manual	O
provider	O
,	O
which	O
allows	O
any	O
SSH	O
Ubuntu	B-Operating_System
machine	O
to	O
be	O
converted	O
into	O
a	O
Juju-managed	O
machine	O
.	O
</s>
<s>
Juju	B-Language
can	O
also	O
be	O
installed	O
on	O
a	O
local	O
Ubuntu	B-Operating_System
machine	O
via	O
LXC	B-Application
operating	B-Application
system	I-Application
–	I-Application
level	I-Application
virtualization	I-Application
and	O
the	O
local	O
provider	O
.	O
</s>
<s>
Juju	B-Language
has	O
both	O
a	O
command	O
line	O
and	O
a	O
GUI	O
.	O
</s>
<s>
Automatically	O
available	O
on	O
every	O
controller	O
,	O
the	O
Juju	B-Language
GUI	O
allows	O
users	O
to	O
visually	O
see	O
what	O
software	O
is	O
currently	O
running	O
in	O
which	O
models	O
.	O
</s>
<s>
Juju	B-Language
also	O
has	O
a	O
concept	O
of	O
bundles	O
.	O
</s>
<s>
A	O
bundle	O
is	O
a	O
portable	O
specification	O
for	O
a	O
model	O
with	O
charms	O
,	O
configuration	O
,	O
and	O
relations	O
,	O
all	O
specified	O
in	O
a	O
declarative	O
YAML	B-Protocol
format	O
.	O
</s>
<s>
A	O
bundle	O
YAML	B-Protocol
file	O
can	O
later	O
be	O
imported	O
into	O
another	O
Juju	B-Language
model	O
and	O
shared	O
with	O
others	O
.	O
</s>
<s>
In	O
this	O
example	O
bundle	O
,	O
two	O
applications	O
are	O
modeled	O
:	O
mediawiki	B-Application
and	O
mysql	B-Application
.	O
</s>
<s>
The	O
Juju	B-Language
Charm	O
Store	O
launched	O
on	O
April	O
3	O
,	O
2012	O
.	O
</s>
<s>
The	O
Charm	O
Store	O
regularly	O
tests	O
charms	O
to	O
notify	O
charm	O
authors	O
when	O
code	O
breaks	O
in	O
addition	O
to	O
ensuring	O
that	O
Juju	B-Language
users	O
have	O
access	O
to	O
the	O
latest	O
versions	O
of	O
charms	O
.	O
</s>
<s>
Juju	B-Language
is	O
available	O
on	O
Ubuntu	B-Operating_System
server	I-Operating_System
,	O
with	O
agents	O
available	O
for	O
Ubuntu	B-Operating_System
,	O
CentOS	O
and	O
Microsoft	B-Application
Windows	I-Application
.	O
</s>
