Splunk Search

Reverse DNS lookups not working

mundus
Path Finder

I'm following the instructions for implementing a reverse DNS lookup at search time. I either get an error saying the fields couldn't be found or I don't get the output I'm expecting.

I copied the external_lookup.py to /etc/apps/search/bin

Transforms.conf:

[dnslookup]
external_cmd = external_lookup.py host ip
fields_list = host, ip

Props.conf:

[nessus]
LOOKUP-rdns = dnslookup ip OUTPUT host AS hostname

I also tried OUTPUTNEW per the example in:

http://docs.splunk.com/Documentation/Splunk/4.3/Knowledge/Addfieldsfromexternaldatasources#Set_up_a_...

What am I doing wrong here? The hostname field is empty if I run a search such as:

sourcetype=nessus NOT timestamps | dedup host | rename dest_ip AS ip | lookup dnslookup ip | table ip, hostname

Thx.

Tags (1)
0 Karma

are0002
Path Finder

Try

[nessus]
LOOKUP-rdns = dnslookup ip AS OUTPUT host AS hostname

0 Karma
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