<s>
dnsmasq	B-Protocol
is	O
free	B-Application
software	I-Application
providing	O
Domain	B-Protocol
Name	I-Protocol
System	I-Protocol
(	O
DNS	B-Protocol
)	O
caching	B-General_Concept
,	O
a	O
Dynamic	B-Protocol
Host	I-Protocol
Configuration	I-Protocol
Protocol	I-Protocol
(	O
DHCP	B-Protocol
)	O
server	B-Application
,	O
router	O
advertisement	O
and	O
network	O
boot	O
features	O
,	O
intended	O
for	O
small	O
computer	B-Architecture
networks	I-Architecture
.	O
</s>
<s>
dnsmasq	B-Protocol
has	O
low	O
requirements	O
for	O
system	O
resources	O
,	O
can	O
run	O
on	O
Linux	B-Application
,	O
BSDs	B-Operating_System
,	O
Android	B-Application
and	O
macOS	B-Application
,	O
and	O
is	O
included	O
in	O
most	O
Linux	B-Application
distributions	I-Application
.	O
</s>
<s>
Consequently	O
,	O
it	O
"	O
is	O
present	O
in	O
a	O
lot	O
of	O
home	O
routers	O
and	O
certain	O
Internet	O
of	O
Things	O
gadgets	O
"	O
and	O
is	O
included	O
in	O
Android	B-Application
.	O
</s>
<s>
dnsmasq	B-Protocol
is	O
a	O
lightweight	O
,	O
easy	O
to	O
configure	O
DNS	B-Protocol
forwarder	O
,	O
designed	O
to	O
provide	O
DNS	B-Protocol
(	O
and	O
optionally	O
DHCP	B-Protocol
and	O
TFTP	B-Device
)	O
services	O
to	O
a	O
small-scale	O
network	O
.	O
</s>
<s>
It	O
can	O
serve	O
the	O
names	O
of	O
local	O
machines	O
which	O
are	O
not	O
in	O
the	O
global	B-Application
DNS	I-Application
.	O
</s>
<s>
dnsmasq	B-Protocol
's	O
DHCP	B-Protocol
server	I-Protocol
supports	O
static	O
and	O
dynamic	O
DHCP	B-Protocol
leases	O
,	O
multiple	O
networks	O
and	O
IP	O
address	O
ranges	O
.	O
</s>
<s>
The	O
DHCP	B-Protocol
server	I-Protocol
integrates	O
with	O
the	O
DNS	B-Protocol
server	I-Protocol
and	O
allows	O
local	O
machines	O
with	O
DHCP-allocated	O
addresses	O
to	O
appear	O
in	O
the	O
DNS	B-Protocol
.	O
</s>
<s>
dnsmasq	B-Protocol
caches	B-General_Concept
DNS	B-Protocol
records	O
,	O
reducing	O
the	O
load	O
on	O
upstream	O
nameservers	O
and	O
improving	O
performance	O
,	O
and	O
can	O
be	O
configured	O
to	O
automatically	O
pick	O
up	O
the	O
addresses	O
of	O
its	O
upstream	O
servers	O
.	O
</s>
<s>
dnsmasq	B-Protocol
accepts	O
DNS	B-Protocol
queries	I-Protocol
and	O
either	O
answers	O
them	O
from	O
a	O
small	O
,	O
local	O
cache	B-General_Concept
or	O
forwards	O
them	O
to	O
a	O
real	O
,	O
recursive	O
DNS	B-Protocol
server	I-Protocol
.	O
</s>
<s>
It	O
loads	O
the	O
contents	O
of	O
/etc/hosts	B-Protocol
,	O
so	O
that	O
local	O
host	O
names	O
which	O
do	O
not	O
appear	O
in	O
the	O
global	B-Application
DNS	I-Application
can	O
be	O
resolved	O
.	O
</s>
<s>
This	O
also	O
means	O
that	O
records	O
added	O
to	O
your	O
local	O
/etc/hosts	B-Protocol
file	I-Protocol
with	O
the	O
format	O
"	O
0.0.0.0	O
annoyingsite.com	O
 "	O
can	O
be	O
used	O
to	O
prevent	O
references	O
to	O
"	O
annoyingsite.com	O
 "	O
from	O
being	O
resolved	O
by	O
your	O
browser	O
.	O
</s>
<s>
dnsmasq	B-Protocol
supports	O
modern	O
Internet	O
standards	O
such	O
as	O
IPv6	B-Protocol
and	O
DNSSEC	B-Protocol
,	O
network	O
booting	O
with	O
support	O
for	O
BOOTP	B-Device
,	O
PXE	B-Device
and	O
TFTP	B-Device
and	O
also	O
Lua	B-Language
scripting	I-Language
.	O
</s>
<s>
Some	O
Internet	O
service-providers	O
rewrite	O
the	O
NXDOMAIN	O
(	O
domain	O
does	O
not	O
exist	O
)	O
responses	O
from	O
DNS	B-Protocol
servers	O
,	O
which	O
forces	O
web	O
browsers	O
to	O
a	O
search	O
page	O
whenever	O
a	O
user	O
attempts	O
to	O
browse	O
to	O
a	O
domain	O
that	O
does	O
not	O
exist	O
.	O
</s>
<s>
dnsmasq	B-Protocol
can	O
filter	O
out	O
these	O
"	O
bogus	O
"	O
NXDOMAIN	O
records	O
,	O
preventing	O
this	O
potentially	O
unwanted	O
behavior	O
.	O
</s>
