Splunk Search

Search for IP Addresses more efficient using wildcards or CIDR ranges

andylee53
New Member

Hello

 

I'm looking to run a search in a Firewall log index for connections to a know IP range and trying to decide which is the more efficient way of doing it. As can be seen I'm excluding certain ports we expect to see traffic on I seem to remember that using "!=" is also considered inefficient as well open to other suggestions for using something else.

Current search looks like this

index="pan_logs" sourcetype="pan:traffic" dest_ip="91.226.*.*" | lookup dnslookup clientip AS src_ip OUTPUT clienthost AS remotehost | search dest_port!=48600 dest_port!=22 | table _time dest_ip dest_port remotehost

Labels (1)
0 Karma

to4kawa
Ultra Champion
index="pan_logs" sourcetype="pan:traffic" dest_ip="91.226.0.0/16" | lookup dnslookup clientip AS src_ip OUTPUT clienthost AS remotehost | table _time dest_ip dest_port remotehost | where dest_port!=48600 OR dest_port!=22
0 Karma

gcusello
SplunkTrust
SplunkTrust

Hi @andylee53 ,

in general the use of != isn't a best practice in searches!

In my experience the CIDR is more efficient than wildcards.

Ciao.

Giuseppe

0 Karma

andylee53
New Member

@gcusello Many Thanks for the reply. I understood about the use of != but cannot think of a better alternative right now

 

Thanks for confirming the CIDR is more efficient I will give it a try

 

Regards

 

Andy

0 Karma
Get Updates on the Splunk Community!

Now Available: Cisco Talos Threat Intelligence Integrations for Splunk Security Cloud ...

At .conf24, we shared that we were in the process of integrating Cisco Talos threat intelligence into Splunk ...

Preparing your Splunk Environment for OpenSSL3

The Splunk platform will transition to OpenSSL version 3 in a future release. Actions are required to prepare ...

Easily Improve Agent Saturation with the Splunk Add-on for OpenTelemetry Collector

Agent Saturation What and Whys In application performance monitoring, saturation is defined as the total load ...