<s>
nslookup	B-Protocol
(	O
from	O
"	O
name	O
server	O
lookup	O
"	O
)	O
is	O
a	O
network	O
administration	O
command-line	B-Application
tool	I-Application
for	O
querying	O
the	O
Domain	B-Protocol
Name	I-Protocol
System	I-Protocol
(	O
DNS	B-Protocol
)	O
to	O
obtain	O
the	O
mapping	O
between	O
domain	O
name	O
and	O
IP	B-Protocol
address	I-Protocol
,	O
or	O
other	O
DNS	B-Protocol
records	O
.	O
</s>
<s>
nslookup	B-Protocol
was	O
a	O
member	O
of	O
the	O
BIND	B-Protocol
name	O
server	O
software	O
.	O
</s>
<s>
Early	O
in	O
the	O
development	O
of	O
BIND	B-Protocol
9	I-Protocol
,	O
the	O
Internet	O
Systems	O
Consortium	O
planned	O
to	O
deprecate	O
nslookup	B-Protocol
in	O
favor	O
of	O
host	B-Protocol
and	O
dig	B-Protocol
.	O
</s>
<s>
This	O
decision	O
was	O
reversed	O
in	O
2004	O
with	O
the	O
release	O
of	O
BIND	O
9.3	O
and	O
nslookup	B-Protocol
has	O
been	O
fully	O
supported	O
since	O
then	O
.	O
</s>
<s>
Unlike	O
dig	B-Protocol
,	O
nslookup	B-Protocol
does	O
not	O
use	O
the	O
operating	O
system	O
's	O
local	O
Domain	B-Protocol
Name	I-Protocol
System	I-Protocol
resolver	O
library	O
to	O
perform	O
its	O
queries	O
,	O
and	O
thus	O
may	O
behave	O
differently	O
.	O
</s>
<s>
Additionally	O
,	O
vendor-provided	O
versions	O
may	O
include	O
output	O
of	O
other	O
sources	O
of	O
name	O
information	O
,	O
such	O
as	O
host	B-Protocol
files	I-Protocol
,	O
and	O
Network	B-Operating_System
Information	I-Operating_System
Service	I-Operating_System
.	O
</s>
<s>
Some	O
behaviors	O
of	O
nslookup	B-Protocol
may	O
be	O
modified	O
by	O
the	O
contents	O
of	O
resolv.conf	B-Protocol
.	O
</s>
<s>
The	O
Linux	B-Application
version	O
of	O
nslookup	B-Protocol
was	O
written	O
by	O
Andrew	O
Cherenson	O
.	O
</s>
<s>
The	O
ReactOS	B-Application
version	O
was	O
developed	O
by	O
Lucas	O
Suggs	O
and	O
is	O
licensed	O
under	O
the	O
GPL	B-License
.	O
</s>
<s>
nslookup	B-Protocol
operates	O
in	O
interactive	O
or	O
non-interactive	O
mode	O
.	O
</s>
<s>
When	O
used	O
interactively	O
by	O
invoking	O
it	O
without	O
arguments	O
or	O
when	O
the	O
first	O
argument	O
is	O
-	O
(	O
minus	O
sign	O
)	O
and	O
the	O
second	O
argument	O
is	O
a	O
hostname	B-Protocol
or	O
Internet	B-Protocol
address	I-Protocol
of	O
a	O
name	O
server	O
,	O
the	O
user	O
issues	O
parameter	O
configurations	O
or	O
requests	O
when	O
presented	O
with	O
the	O
nslookup	B-Protocol
prompt	O
(	O
>	O
)	O
.	O
</s>
<s>
When	O
no	O
arguments	O
are	O
given	O
,	O
then	O
the	O
command	B-Application
queries	O
the	O
default	O
server	O
.	O
</s>
<s>
The	O
-	O
(	O
minus	O
sign	O
)	O
invokes	O
subcommands	O
which	O
are	O
specified	O
on	O
the	O
command	B-Application
line	I-Application
and	O
should	O
precede	O
nslookup	B-Protocol
commands	O
.	O
</s>
<s>
when	O
the	O
first	O
argument	O
is	O
a	O
name	O
or	O
Internet	B-Protocol
address	I-Protocol
of	O
the	O
host	B-Protocol
being	O
searched	O
,	O
parameters	O
and	O
the	O
query	O
are	O
specified	O
as	O
command	B-Application
line	I-Application
arguments	O
in	O
the	O
invocation	O
of	O
the	O
program	O
.	O
</s>
<s>
The	O
non	O
interactive	O
mode	O
searches	O
the	O
information	O
for	O
a	O
specified	O
host	B-Protocol
using	O
the	O
default	O
name	O
server	O
.	O
</s>
