<s>
The	O
Intelligent	O
Platform	O
Management	O
Interface	O
(	O
IPMI	O
)	O
is	O
a	O
set	O
of	O
computer	B-Application
interface	I-Application
specifications	O
for	O
an	O
autonomous	O
computer	O
subsystem	O
that	O
provides	O
management	O
and	O
monitoring	O
capabilities	O
independently	O
of	O
the	O
host	O
system	O
's	O
CPU	B-Device
,	O
firmware	B-Application
(	O
BIOS	B-Operating_System
or	O
UEFI	B-Architecture
)	O
and	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
IPMI	O
defines	O
a	O
set	O
of	O
interfaces	B-Application
used	O
by	O
system	B-Application
administrators	I-Application
for	O
out-of-band	B-Application
management	I-Application
of	O
computer	B-General_Concept
systems	I-General_Concept
and	O
monitoring	O
of	O
their	O
operation	O
.	O
</s>
<s>
For	O
example	O
,	O
IPMI	O
provides	O
a	O
way	O
to	O
manage	O
a	O
computer	O
that	O
may	O
be	O
powered	O
off	O
or	O
otherwise	O
unresponsive	O
by	O
using	O
a	O
network	B-Architecture
connection	O
to	O
the	O
hardware	O
rather	O
than	O
to	O
an	O
operating	B-General_Concept
system	I-General_Concept
or	O
login	O
shell	O
.	O
</s>
<s>
Another	O
use	O
case	O
may	O
be	O
installing	O
a	O
custom	O
operating	B-General_Concept
system	I-General_Concept
remotely	O
.	O
</s>
<s>
Without	O
IPMI	O
,	O
installing	O
a	O
custom	O
operating	B-General_Concept
system	I-General_Concept
may	O
require	O
an	O
administrator	B-Application
to	O
be	O
physically	O
present	O
near	O
the	O
computer	O
,	O
insert	O
a	O
DVD	O
or	O
a	O
USB	O
flash	O
drive	O
containing	O
the	O
OS	O
installer	O
and	O
complete	O
the	O
installation	O
process	O
using	O
a	O
monitor	O
and	O
a	O
keyboard	O
.	O
</s>
<s>
Using	O
IPMI	O
,	O
an	O
administrator	B-Application
can	O
mount	O
an	O
ISO	B-General_Concept
image	I-General_Concept
,	O
simulate	O
an	O
installer	O
DVD	O
,	O
and	O
perform	O
the	O
installation	O
remotely	O
.	O
</s>
<s>
The	O
successor	O
to	O
the	O
IPMI	O
is	O
Redfish	B-Application
.	O
</s>
<s>
As	O
a	O
message-based	O
,	O
hardware-level	O
interface	O
specification	O
,	O
IPMI	O
operates	O
independently	O
of	O
the	O
operating	B-General_Concept
system	I-General_Concept
(	O
OS	O
)	O
to	O
allow	O
administrators	O
to	O
manage	O
a	O
system	O
remotely	O
in	O
the	O
absence	O
of	O
an	O
operating	B-General_Concept
system	I-General_Concept
or	O
of	O
the	O
system	B-Application
management	I-Application
software	O
.	O
</s>
<s>
System	B-Application
administrators	I-Application
can	O
use	O
IPMI	O
messaging	O
to	O
monitor	O
platform	O
status	O
(	O
such	O
as	O
system	O
temperatures	O
,	O
voltages	O
,	O
fans	O
,	O
power	O
supplies	O
and	O
chassis	O
intrusion	O
)	O
;	O
to	O
query	O
inventory	O
information	O
;	O
to	O
review	O
hardware	O
logs	O
of	O
out-of-range	O
conditions	O
;	O
or	O
to	O
perform	O
recovery	O
procedures	O
such	O
as	O
issuing	O
requests	O
from	O
a	O
remote	O
console	O
through	O
the	O
same	O
connections	O
e.g.	O
</s>
<s>
system	O
power-down	O
and	O
rebooting	O
,	O
or	O
configuring	O
watchdog	B-Application
timers	I-Application
.	O
</s>
<s>
The	O
standard	O
also	O
defines	O
an	O
alerting	O
mechanism	O
for	O
the	O
system	O
to	O
send	O
a	O
simple	B-Protocol
Network	I-Protocol
Management	I-Protocol
Protocol	I-Protocol
(	O
SNMP	B-Protocol
)	O
platform	O
event	O
trap	O
(	O
PET	O
)	O
.	O
</s>
<s>
The	O
monitored	O
system	O
may	O
be	O
powered	O
off	O
,	O
but	O
must	O
be	O
connected	O
to	O
a	O
power	O
source	O
and	O
to	O
the	O
monitoring	O
medium	O
,	O
typically	O
a	O
local	B-General_Concept
area	I-General_Concept
network	I-General_Concept
(	O
LAN	B-General_Concept
)	O
connection	O
.	O
</s>
<s>
IPMI	O
can	O
also	O
function	O
after	O
the	O
operating	B-General_Concept
system	I-General_Concept
has	O
started	O
,	O
and	O
exposes	O
management	O
data	O
and	O
structures	O
to	O
the	O
system	B-Application
management	I-Application
software	O
.	O
</s>
<s>
IPMI	O
prescribes	O
only	O
the	O
structure	O
and	O
format	O
of	O
the	O
interfaces	B-Application
as	O
a	O
standard	O
,	O
while	O
detailed	O
implementations	O
may	O
vary	O
.	O
</s>
<s>
An	O
implementation	O
of	O
IPMI	O
version	O
1.5	O
can	O
communicate	O
via	O
a	O
direct	O
out-of-band	O
LAN	B-General_Concept
or	O
serial	B-Protocol
connection	O
or	O
via	O
a	O
side-band	O
LAN	B-General_Concept
connection	O
to	O
a	O
remote	O
client	B-Protocol
.	O
</s>
<s>
The	O
side-band	O
LAN	B-General_Concept
connection	O
utilizes	O
the	O
board	O
network	B-Protocol
interface	I-Protocol
controller	I-Protocol
(	O
NIC	O
)	O
.	O
</s>
<s>
This	O
solution	O
is	O
less	O
expensive	O
than	O
a	O
dedicated	O
LAN	B-General_Concept
connection	O
but	O
also	O
has	O
limited	O
bandwidth	O
and	O
security	O
issues	O
.	O
</s>
<s>
Systems	O
compliant	O
with	O
IPMI	O
version	O
2.0	O
can	O
also	O
communicate	O
via	O
serial	B-General_Concept
over	I-General_Concept
LAN	I-General_Concept
,	O
whereby	O
serial	B-Protocol
console	O
output	O
can	O
be	O
remotely	O
viewed	O
over	O
the	O
LAN	B-General_Concept
.	O
</s>
<s>
Systems	O
implementing	O
IPMI	O
2.0	O
typically	O
also	O
include	O
KVM	B-Application
over	O
IP	O
,	O
remote	B-Protocol
virtual	I-Protocol
media	I-Protocol
and	O
out-of-band	O
embedded	O
web-server	O
interface	O
functionality	O
,	O
although	O
strictly	O
speaking	O
,	O
these	O
lie	O
outside	O
of	O
the	O
scope	O
of	O
the	O
IPMI	O
interface	O
standard	O
.	O
</s>
<s>
DCMI	B-Application
(	O
Data	B-Application
Center	I-Application
Manageability	I-Application
Interface	I-Application
)	O
is	O
a	O
similar	O
standard	O
based	O
on	O
IPMI	O
but	O
designed	O
to	O
be	O
more	O
suitable	O
for	O
Data	B-Operating_System
Center	I-Operating_System
management	O
:	O
it	O
uses	O
the	O
interfaces	B-Application
defined	O
in	O
IPMI	O
,	O
but	O
minimizes	O
the	O
number	O
of	O
optional	O
interfaces	B-Application
and	O
includes	O
power	O
capping	O
control	O
,	O
among	O
other	O
differences	O
.	O
</s>
<s>
An	O
IPMI	O
sub-system	O
consists	O
of	O
a	O
main	O
controller	O
,	O
called	O
the	O
baseboard	B-Device
management	I-Device
controller	I-Device
(	O
BMC	O
)	O
and	O
other	O
management	O
controllers	O
distributed	O
among	O
different	O
system	O
modules	O
that	O
are	O
referred	O
to	O
as	O
satellite	O
controllers	O
.	O
</s>
<s>
RMCP+	O
(	O
a	O
UDP-based	O
protocol	O
with	O
stronger	O
authentication	O
than	O
RMCP	O
)	O
is	O
used	O
for	O
IPMI	O
over	O
LAN	B-General_Concept
.	O
</s>
<s>
A	O
BMC	O
utilized	O
for	O
embedded	O
applications	O
may	O
have	O
limited	O
memory	O
and	O
require	O
optimized	O
firmware	B-Application
code	O
for	O
implementation	O
of	O
the	O
full	O
IPMI	O
functionality	O
.	O
</s>
<s>
The	O
firmware	B-Application
implementing	O
the	O
IPMI	O
interfaces	B-Application
is	O
provided	O
by	O
various	O
vendors	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
board	O
may	O
contain	O
sensors	O
for	O
temperature	O
,	O
fan	B-Application
speed	O
,	O
and	O
voltage	O
.	O
</s>
<s>
The	O
baseboard	B-Device
management	I-Device
controller	I-Device
(	O
BMC	O
)	O
provides	O
the	O
intelligence	O
in	O
the	O
IPMI	O
architecture	O
.	O
</s>
<s>
It	O
is	O
a	O
specialized	O
microcontroller	B-Architecture
embedded	O
on	O
the	O
motherboard	B-Device
of	O
a	O
computer	O
–	O
generally	O
a	O
server	B-Application
.	O
</s>
<s>
BMC	O
has	O
its	O
dedicated	O
firmware	B-Application
and	O
RAM	O
.	O
</s>
<s>
Different	O
types	O
of	O
sensors	O
built	O
into	O
the	O
computer	O
system	O
report	O
to	O
the	O
BMC	O
on	O
parameters	O
such	O
as	O
temperature	O
,	O
cooling	O
fan	B-Application
speeds	O
,	O
power	O
status	O
,	O
operating	B-General_Concept
system	I-General_Concept
(	O
OS	O
)	O
status	O
,	O
etc	O
.	O
</s>
<s>
The	O
BMC	O
monitors	O
the	O
sensors	O
and	O
can	O
send	O
alerts	O
to	O
a	O
system	B-Application
administrator	I-Application
via	O
the	O
network	B-Architecture
if	O
any	O
of	O
the	O
parameters	O
do	O
not	O
stay	O
within	O
pre-set	O
limits	O
,	O
indicating	O
a	O
potential	O
failure	O
of	O
the	O
system	O
.	O
</s>
<s>
The	O
administrator	B-Application
can	O
also	O
remotely	O
communicate	O
with	O
the	O
BMC	O
to	O
take	O
some	O
corrective	O
actions	O
–	O
such	O
as	O
resetting	O
or	O
power	O
cycling	O
the	O
system	O
to	O
get	O
a	O
hung	O
OS	O
running	O
again	O
.	O
</s>
<s>
Systems	O
compliant	O
with	O
IPMI	O
version	O
2.0	O
can	O
also	O
communicate	O
via	O
serial	B-General_Concept
over	I-General_Concept
LAN	I-General_Concept
,	O
whereby	O
serial	B-Protocol
console	O
output	O
can	O
be	O
remotely	O
viewed	O
over	O
the	O
LAN	B-General_Concept
.	O
</s>
<s>
Systems	O
implementing	O
IPMI	O
2.0	O
typically	O
also	O
include	O
KVM	B-Application
over	O
IP	O
,	O
remote	B-Protocol
virtual	I-Protocol
media	I-Protocol
and	O
out-of-band	O
embedded	O
web-server	O
interface	O
functionality	O
,	O
although	O
strictly	O
speaking	O
,	O
these	O
lie	O
outside	O
of	O
the	O
scope	O
of	O
the	O
IPMI	O
interface	O
standard	O
.	O
</s>
<s>
Physical	O
interfaces	B-Application
to	O
the	O
BMC	O
include	O
SMBuses	O
,	O
an	O
RS-232	O
serial	B-Protocol
console	O
,	O
address	O
and	O
data	O
lines	O
and	O
an	O
IPMB	O
,	O
that	O
enables	O
the	O
BMC	O
to	O
accept	O
IPMI	O
request	O
messages	O
from	O
other	O
management	O
controllers	O
in	O
the	O
system	O
.	O
</s>
<s>
A	O
direct	O
serial	B-Protocol
connection	O
to	O
the	O
BMC	O
is	O
not	O
encrypted	O
as	O
the	O
connection	O
itself	O
is	O
secure	O
.	O
</s>
<s>
Connection	O
to	O
the	O
BMC	O
over	O
LAN	B-General_Concept
may	O
or	O
may	O
not	O
use	O
encryption	O
depending	O
on	O
the	O
security	O
concerns	O
of	O
the	O
user	O
.	O
</s>
<s>
OpenBMC	B-Application
is	O
a	O
Linux	B-Operating_System
Foundation	I-Operating_System
Collaborative	O
open-source	O
BMC	O
project	O
.	O
</s>
<s>
On	O
2	O
July	O
2013	O
,	O
Rapid7	B-Application
published	O
a	O
guide	O
to	O
security	O
penetration	O
testing	O
of	O
the	O
latest	O
IPMI	O
2.0	O
protocol	O
and	O
implementations	O
by	O
various	O
vendors	O
.	O
</s>
<s>
Some	O
sources	O
in	O
2013	O
were	O
advising	O
against	O
using	O
the	O
older	O
version	O
of	O
IPMI	O
,	O
due	O
to	O
security	O
concerns	O
related	O
to	O
the	O
design	O
and	O
vulnerabilities	O
of	O
Baseboard	B-Device
Management	I-Device
Controllers	I-Device
(	O
BMCs	O
)	O
.	O
</s>
<s>
However	O
,	O
like	O
for	O
any	O
other	O
management	O
interface	O
,	O
best	O
security	O
practices	O
dictate	O
the	O
placement	O
of	O
the	O
IPMI	O
management	O
port	O
on	O
a	O
dedicated	O
management	O
LAN	B-General_Concept
or	O
VLAN	O
restricted	O
to	O
trusted	O
Administrators	O
.	O
</s>
<s>
The	O
DMTF	O
organization	O
has	O
developed	O
a	O
secure	O
and	O
scalable	O
interface	O
specification	O
called	O
to	O
work	O
in	O
modern	O
datacenter	B-Operating_System
environments	O
.	O
</s>
<s>
The	O
use	O
of	O
default	O
short	O
passwords	O
,	O
or	O
"	O
cipher	O
0	O
"	O
hacks	O
can	O
be	O
easily	O
overcome	O
with	O
the	O
use	O
of	O
a	O
RADIUS	B-Protocol
server	I-Protocol
for	O
Authentication	O
,	O
Authorization	O
,	O
and	O
Accounting	O
over	O
SSL	O
as	O
is	O
typical	O
in	O
a	O
datacenter	B-Operating_System
or	O
any	O
medium	O
to	O
large	O
deployment	O
.	O
</s>
<s>
The	O
user	O
's	O
RADIUS	B-Protocol
server	I-Protocol
can	O
be	O
configured	O
to	O
store	O
AAA	O
securely	O
in	O
an	O
LDAP	O
database	O
using	O
either	O
FreeRADIUS/OpenLDAP	O
or	O
Microsoft	O
Active	O
Directory	O
and	O
related	O
services	O
.	O
</s>
<s>
Role-based	O
access	O
is	O
supported	O
with	O
three	O
roles	O
available	O
:	O
Administrator	B-Application
,	O
Operator	O
and	O
User	O
.	O
</s>
<s>
Overall	O
,	O
the	O
User	O
role	O
has	O
read-only	O
access	O
of	O
the	O
BMC	O
and	O
no	O
remote	O
control	O
ability	O
such	O
as	O
power	O
cycle	O
or	O
the	O
ability	O
to	O
view	O
or	O
log	O
into	O
the	O
main	O
CPU	B-Device
on	O
the	O
motherboard	B-Device
.	O
</s>
<s>
The	O
User	O
role	O
is	O
typically	O
used	O
to	O
monitor	O
sensor	O
readings	O
,	O
after	O
an	O
SNMP	B-Protocol
alert	O
has	O
been	O
received	O
by	O
SNMP	B-Protocol
Network	B-Architecture
Monitoring	O
Software	O
.	O
</s>
<s>
The	O
Administrator	B-Application
role	O
is	O
used	O
to	O
configure	O
the	O
BMC	O
on	O
first	O
boot	O
during	O
the	O
commissioning	O
of	O
the	O
system	O
when	O
first	O
installed	O
.	O
</s>
<s>
Therefore	O
,	O
the	O
prudent	O
best	O
practice	O
is	O
to	O
disable	O
the	O
use	O
of	O
the	O
Operator	O
and	O
Administrator	B-Application
roles	O
in	O
LDAP/RADIUS	O
,	O
and	O
only	O
enable	O
them	O
when	O
needed	O
by	O
the	O
LDAP/RADIUS	O
administrator	B-Application
.	O
</s>
<s>
For	O
example	O
,	O
in	O
RADIUS	B-Protocol
a	O
role	O
can	O
have	O
its	O
setting	O
Auth-Type	O
changed	O
to	O
:	O
</s>
<s>
Doing	O
so	O
will	O
prevent	O
RAKP	O
hash	O
attacks	O
from	O
succeeding	O
since	O
the	O
username	O
will	O
be	O
rejected	O
by	O
the	O
RADIUS	B-Protocol
server	I-Protocol
.	O
</s>
