<s>
Checkmk	B-Protocol
is	O
software	O
developed	O
in	O
Python	B-Language
and	O
C++	B-Language
for	O
IT	B-Application
Infrastructure	I-Application
monitoring	O
.	O
</s>
<s>
It	O
is	O
used	O
for	O
the	O
monitoring	O
of	O
servers	B-Application
,	O
applications	B-Application
,	O
networks	O
,	O
cloud	O
infrastructures	O
(	O
public	O
,	O
private	O
,	O
hybrid	O
)	O
,	O
containers	B-Application
,	O
storage	O
,	O
databases	O
and	O
environment	O
sensors	O
.	O
</s>
<s>
Checkmk	B-Protocol
is	O
available	O
in	O
three	O
editions	O
:	O
an	O
open	B-Application
source	I-Application
edition	O
(	O
"	O
Checkmk	B-Protocol
Raw	O
Edition	O
–	O
CRE	O
"	O
)	O
,	O
a	O
commercial	O
enterprise	O
edition	O
(	O
"	O
Checkmk	B-Protocol
Enterprise	O
Edition	O
–	O
CEE	O
"	O
)	O
and	O
a	O
commercial	O
edition	O
for	O
managed	O
services	B-Protocol
providers	O
(	O
"	O
Checkmk	B-Protocol
Managed	O
Services	B-Protocol
Edition	O
–	O
CME	O
"	O
)	O
.	O
</s>
<s>
These	O
Checkmk-Editions	O
are	O
available	O
for	O
a	O
range	O
of	O
platforms	O
,	O
in	O
particular	O
for	O
various	O
versions	O
of	O
Debian	O
,	O
Ubuntu	B-Operating_System
,	O
SLES	O
and	O
Red	O
Hat	O
/	O
CentOS	O
,	O
and	O
also	O
as	O
a	O
Docker	B-Language
Image	O
.	O
</s>
<s>
In	O
addition	O
,	O
physical	O
appliances	O
of	O
various	O
sizes	O
as	O
well	O
as	O
a	O
virtual	O
appliance	O
are	O
offered	O
to	O
simplify	O
the	O
administration	O
of	O
the	O
underlying	O
operating	B-General_Concept
system	I-General_Concept
through	O
a	O
graphical	B-Application
user	I-Application
interface	I-Application
and	O
to	O
enable	O
high-availability	O
solutions	O
.	O
</s>
<s>
The	O
agents	O
used	O
by	O
Checkmk	B-Protocol
to	O
collect	O
data	O
are	O
available	O
for	O
11	O
platforms	O
,	O
including	O
Windows	B-Application
.	O
</s>
<s>
Checkmk	B-Protocol
originated	O
in	O
2008	O
as	O
an	O
Agent-substituting	O
shell	B-Language
script	I-Language
for	O
Inetd	B-Protocol
,	O
and	O
was	O
published	O
in	O
April	O
2009	O
under	O
GPL	B-License
.	O
</s>
<s>
It	O
was	O
initially	O
based	O
on	O
Nagios	B-Application
,	O
and	O
extended	O
this	O
with	O
a	O
number	O
of	O
new	O
components	O
.	O
</s>
<s>
The	O
open	B-Application
source	I-Application
edition	O
(	O
Checkmk	B-Protocol
Raw	O
Edition	O
)	O
also	O
continues	O
to	O
be	O
based	O
on	O
the	O
Nagios-core	O
,	O
and	O
bundles	O
this	O
with	O
additional	O
open	B-Application
source	I-Application
components	O
into	O
a	O
complete	O
system	O
.	O
</s>
<s>
Over	O
many	O
years	O
Checkmk	B-Protocol
's	O
commercial	O
editions	O
have	O
evolved	O
into	O
a	O
self-contained	O
monitoring	O
system	O
–	O
one	O
that	O
has	O
replaced	O
all	O
of	O
the	O
essential	O
Nagios	B-Application
components	O
with	O
its	O
own	O
–	O
including	O
its	O
very	O
own	O
monitoring	O
core	O
.	O
</s>
<s>
The	O
majority	O
of	O
the	O
developments	O
for	O
the	O
commercial	O
editions	O
,	O
in	O
particular	O
all	O
plug-ins	B-Application
,	O
are	O
also	O
available	O
into	O
the	O
Checkmk	B-Protocol
Raw	O
Edition	O
.	O
</s>
<s>
While	O
in	O
the	O
past	O
Checkmk	B-Protocol
was	O
designed	O
for	O
monitoring	O
large	O
and	O
heterogeneous	O
on-premise	B-General_Concept
environments	O
,	O
from	O
version	O
1.5	O
+	O
(	O
1.5p12	O
)	O
it	O
also	O
supports	O
the	O
monitoring	O
of	O
AWS	B-Application
,	O
Azure	B-Application
,	O
Docker	B-Language
and	O
Kubernetes	B-General_Concept
services	B-Protocol
.	O
</s>
<s>
Checkmk	B-Protocol
is	O
being	O
developed	O
by	O
tribe29	O
GmbH	O
in	O
Munich	O
Germany	O
,	O
which	O
until	O
16.04.2019	O
operated	O
under	O
the	O
name	O
of	O
Mathias	O
Kettner	O
GmbH	O
.	O
</s>
<s>
Together	O
with	O
the	O
company	O
name	O
change	O
,	O
the	O
product	O
name	O
"	O
Check_MK	O
"	O
was	O
also	O
changed	O
to	O
"	O
Checkmk	B-Protocol
"	O
.	O
</s>
<s>
The	O
open	B-Application
source	I-Application
edition	O
is	O
available	O
under	O
different	O
open	B-Application
source	I-Application
licenses	O
–	O
mostly	O
GPLv2	O
,	O
while	O
large	O
parts	O
of	O
the	O
commercial	O
editions	O
run	O
under	O
the	O
proprietary	O
"	O
Checkmk	B-Protocol
Enterprise	O
License	O
"	O
.	O
</s>
<s>
Checkmk	B-Protocol
combines	O
three	O
types	O
of	O
IT	O
monitoring	O
:	O
</s>
<s>
Metric-based	O
monitoring	O
that	O
enables	O
the	O
recording	O
and	O
analysis	O
of	O
time	O
series	O
graphs	O
using	O
a	O
HTML5-based	O
graphing	O
system	O
.	O
</s>
<s>
An	O
integration	O
with	O
Grafana	B-Protocol
is	O
available	O
as	O
well	O
.	O
</s>
<s>
In	O
order	O
to	O
ensure	O
a	O
very	O
broad	O
monitoring	O
,	O
Checkmk	B-Protocol
currently	O
has	O
1700+	O
plug-ins	B-Application
in	O
each	O
edition	O
–	O
all	O
of	O
which	O
are	O
licensed	O
under	O
GPLv2	O
.	O
</s>
<s>
These	O
plug-ins	B-Application
are	O
maintained	O
as	O
part	O
of	O
the	O
product	O
and	O
are	O
regularly	O
supplemented	O
with	O
additional	O
plug-ins	B-Application
or	O
extensions	O
.	O
</s>
<s>
Connecting	O
existing	O
legacy	B-Device
Nagios	B-Application
plug-ins	B-Application
is	O
possible	O
as	O
well	O
.	O
</s>
<s>
To	O
simplify	O
setup	O
and	O
operation	O
,	O
all	O
components	O
of	O
Checkmk	B-Protocol
are	O
delivered	O
fully	O
integrated	O
.	O
</s>
<s>
A	O
rule-based	O
1:n	B-Application
configuration	O
,	O
as	O
well	O
as	O
a	O
high	O
degree	O
of	O
automation	O
significantly	O
accelerate	O
workflows	B-Operating_System
.	O
</s>
<s>
In	O
addition	O
,	O
there	O
are	O
also	O
playbooks	O
for	O
the	O
use	O
of	O
configuration	O
and	O
deployment	O
tools	O
such	O
as	O
Ansible	B-Language
or	O
Salt	B-Application
.	O
</s>
<s>
Checkmk	B-Protocol
is	O
often	O
used	O
in	O
very	O
large	O
distributed	O
environments	O
where	O
a	O
high	O
number	O
of	O
sites	O
(	O
e.g.	O
</s>
<s>
This	O
is	O
possible	O
,	O
among	O
other	O
things	O
,	O
because	O
Checkmk	B-Protocol
's	O
microcore	O
consumes	O
much	O
less	O
CPU	B-General_Concept
resources	O
than	O
,	O
for	O
example	O
Nagios	B-Application
,	O
and	O
therefore	O
offers	O
a	O
significantly	O
higher	O
performance	O
on	O
the	O
same	O
hardware	O
.	O
</s>
<s>
Furthermore	O
the	O
non-persistent	O
data	O
is	O
stored	O
in-memory	O
in	O
RAM	B-Architecture
which	O
significantly	O
improves	O
the	O
access	O
time	O
.	O
</s>
<s>
Checkmk	B-Protocol
RE	O
uses	O
Nagios	B-Application
monitoring	O
core	O
.	O
</s>
<s>
It	O
does	O
n't	O
offer	O
container	B-Application
monitoring	O
and	O
requires	O
a	O
reboot	O
to	O
apply	O
configuration	O
changes	O
.	O
</s>
<s>
Checkmk	B-Protocol
commercial	O
edition	O
uses	O
proprietary	O
"	O
Checkmk	B-Protocol
Microcore	O
"	O
(	O
CMC	O
)	O
monitoring	O
core	O
,	O
written	O
in	O
C++	B-Language
.	O
</s>
<s>
It	O
has	O
better	O
performance	O
than	O
Checkmk	B-Protocol
RE	O
core	O
.	O
</s>
<s>
It	O
supports	O
recording	O
of	O
objects	O
with	O
a	O
short	O
lifespan	O
,	O
such	O
as	O
containers	B-Application
.	O
</s>
<s>
Checkmk	B-Protocol
offers	O
self-contained	O
service	B-Protocol
discovery	I-Protocol
and	O
settings	O
generation	O
.	O
</s>
<s>
Checkmk	B-Protocol
uses	O
its	O
own	O
method	O
when	O
carrying	O
out	O
the	O
checks	O
.	O
</s>
<s>
Checkmk	B-Protocol
uses	O
different	O
methods	O
to	O
access	O
the	O
data	O
in	O
the	O
target	O
systems	O
.	O
</s>
<s>
These	O
include	O
agents	O
installed	O
on	O
the	O
target	O
system	O
,	O
"	O
special	O
agents	O
"	O
running	O
on	O
the	O
monitoring	O
server	O
and	O
communicating	O
with	O
the	O
API	B-Application
of	O
the	O
target	O
system	O
,	O
the	O
SNMP	B-Protocol
API	B-Application
for	O
monitoring	O
,	O
for	O
example	O
,	O
network	O
devices	O
and	O
printers	O
,	O
and	O
HTTP/TCP	O
protocols	O
to	O
communicate	O
with	O
web	O
and	O
internet	O
services	B-Protocol
.	O
</s>
<s>
By	O
default	O
,	O
Checkmk	B-Protocol
follows	O
the	O
"	O
pull	O
principle	O
"	O
,	O
i.e.	O
</s>
<s>
As	O
an	O
alternative	O
,	O
however	O
,	O
a	O
"	O
push	O
"	O
can	O
be	O
configured	O
with	O
which	O
the	O
system	O
transfers	O
its	O
data	O
directly	O
to	O
Checkmk	B-Protocol
or	O
to	O
an	O
intermediate	O
host	O
.	O
</s>
<s>
Livestatus	O
is	O
the	O
main	O
interface	O
in	O
Checkmk	B-Protocol
.	O
</s>
<s>
It	O
provides	O
live	O
access	O
to	O
all	O
data	O
from	O
the	O
monitored	O
hosts	O
and	O
services	B-Protocol
.	O
</s>
<s>
The	O
data	O
is	O
fetched	O
directly	O
from	O
the	O
RAM	B-Architecture
,	O
which	O
avoids	O
slow	O
hard	O
disk	O
access	O
and	O
gives	O
fast	O
access	O
to	O
the	O
information	O
without	O
overloading	O
the	O
system	O
too	O
much	O
.	O
</s>
<s>
Multisite	O
is	O
Checkmk	B-Protocol
’s	O
web	O
GUI	B-Application
.	O
</s>
<s>
In	O
addition	O
to	O
having	O
a	O
quick	O
page	O
layout	O
,	O
it	O
offers	O
user-definable	O
views	O
and	O
dashboards	O
,	O
distributed	O
monitoring	O
by	O
integrating	O
multiple	O
monitoring	O
instances	O
via	O
Livestatus	O
,	O
integration	O
of	O
NagVis	O
,	O
an	O
integrated	O
LDAP	B-Protocol
connection	O
,	O
access	O
to	O
status	O
data	O
via	O
web	O
services	B-Protocol
,	O
and	O
much	O
more	O
.	O
</s>
<s>
The	O
web	O
GUI	B-Application
is	O
available	O
in	O
English	O
and	O
German	O
.	O
</s>
<s>
Checkmk	B-Protocol
is	O
completely	O
administrable	O
via	O
the	O
browser	B-Application
via	O
its	O
Setup	O
module	O
.	O
</s>
<s>
Existing	O
role-based	O
access	O
controls	O
(	O
LDAP	B-Protocol
,	O
AD	O
)	O
can	O
be	O
used	O
for	O
this	O
.	O
</s>
<s>
Checkmk	B-Protocol
works	O
rule-based	O
,	O
so	O
that	O
the	O
configuration	O
remains	O
intuitive	O
even	O
in	O
complex	O
environments	O
,	O
and	O
the	O
necessary	O
effort	O
is	O
low	O
.	O
</s>
<s>
Automatic	O
discovery	O
and	O
configuration	O
,	O
as	O
well	O
as	O
the	O
automatic	O
agent	B-General_Concept
update	O
further	O
accelerate	O
the	O
configuration	O
process	O
.	O
</s>
<s>
An	O
HTTP	B-Protocol
API	B-Application
can	O
also	O
be	O
used	O
to	O
integrate	O
CMDBs	B-Application
for	O
accelerated	O
configuration	O
.	O
</s>
<s>
Checkmk	B-Protocol
includes	O
integrations	O
to	O
email	O
and	O
SMS	O
gateways	O
as	O
well	O
as	O
to	O
communication	O
and	O
IT	O
service-management	O
solutions	O
such	O
as	O
Slack	B-Protocol
,	O
Jira	B-Protocol
,	O
PagerDuty	O
,	O
OpsGenie	O
,	O
VictorOps	O
and	O
ServiceNow	B-General_Concept
.	O
</s>
<s>
The	O
BI	O
module	O
is	O
integrated	O
into	O
the	O
graphical	B-Application
user	I-Application
interface	I-Application
.	O
</s>
<s>
It	O
aggregates	O
the	O
overall	O
status	O
of	O
business	O
processes	O
,	O
their	O
dependency	O
on	O
complex	O
applications	B-Application
and	O
IT	B-Application
infrastructure	I-Application
elements	O
from	O
many	O
individual	O
hosts	O
and	O
services	B-Protocol
in	O
a	O
rule-based	O
manner	O
.	O
</s>
<s>
It	O
can	O
also	O
be	O
used	O
to	O
represent	O
applications	B-Application
made	O
up	O
of	O
microservices	O
,	O
which	O
in	O
turn	O
consist	O
of	O
Kubernetes	B-General_Concept
pods	O
and	O
deployments	O
.	O
</s>
<s>
The	O
Event	O
Console	O
integrates	O
the	O
processing	O
of	O
log	O
messages	O
and	O
SNMP	B-Protocol
traps	O
into	O
the	O
monitoring	O
.	O
</s>
<s>
It	O
also	O
has	O
a	O
built-in	O
syslog	B-Protocol
daemon	O
that	O
receives	O
messages	O
directly	O
on	O
port	O
514	O
,	O
and	O
an	O
SNMP	B-Protocol
trap	O
receiver	O
that	O
receives	O
traps	O
on	O
port	O
162	O
.	O
</s>
<s>
The	O
commercial	O
Checkmk	B-Protocol
editions	O
use	O
their	O
own	O
metric	O
and	O
graphing	O
system	O
.	O
</s>
<s>
Time	O
series	O
metrics	O
can	O
be	O
analysed	O
over	O
long	O
intervals	O
using	O
interactive	O
HTML5	B-Application
graphs	O
.	O
</s>
<s>
Data	O
can	O
be	O
imported	O
from	O
a	O
variety	O
of	O
data	O
sources	O
and	O
metrics	O
formats	O
(	O
JSON	B-General_Concept
,	O
XML	B-Protocol
,	O
SNMP	B-Protocol
etc	O
.	O
)	O
</s>
<s>
Alternatively	O
,	O
Graphite	B-Application
or	O
InfluxDB	B-Language
can	O
be	O
connected	O
via	O
an	O
export	O
interface	O
.	O
</s>
<s>
From	O
CEE	O
version	O
1.5p16	O
there	O
is	O
also	O
a	O
plug-in	B-Application
available	O
for	O
integrating	O
data	O
directly	O
from	O
Checkmk	B-Protocol
into	O
Grafana	B-Protocol
for	O
visualization	O
purposes	O
.	O
</s>
<s>
The	O
Checkmk	B-Protocol
Raw	O
Edition	O
currently	O
uses	O
PNP4Nagios	O
as	O
its	O
graphing	O
system	O
.	O
</s>
<s>
Reporting	O
enables	O
the	O
direct	O
delivery	O
of	O
PDF	B-Application
reports	O
,	O
ad-hoc	O
or	O
automatically	O
,	O
at	O
regular	O
intervals	O
.	O
</s>
<s>
The	O
reporting	O
is	O
only	O
available	O
in	O
the	O
commercial	O
versions	O
of	O
Checkmk	B-Protocol
.	O
</s>
<s>
The	O
Configuration	B-Application
Management	I-Application
Database	I-Application
(	O
CMDB	B-Application
)	O
i-doit	O
has	O
a	O
deep	O
integration	O
that	O
enables	O
the	O
exchange	O
of	O
CMDB	B-Application
data	O
with	O
monitoring	O
data	O
.	O
</s>
