Splunk Search

How to write a query to check IP addresses in Subnets?

POR160893
Builder

Hi,

I am trying to establish a query that checks whether a random src IP is in a specific subnet.

However, all the subnets and IP addresses are in String format and I am unable to establish any mathematical relationship between the conditions.

Here is a part of my current query:

| inputlookup ABC.csv
| eval ip = 10.1.2.342

| eval AMERICAS =if(ip >= 10.0.0.1 OR ip <= 10.63.255.254,"NOK","OK")

| table AMERICAS

 

Can you please help?

Many thanks as always,

Labels (5)
0 Karma

isoutamo
SplunkTrust
SplunkTrust

Hi

I expecting that your ip is like "10.1.2.34" not "10.1.2.342" and you have e.g. subnets 10.0.0.0 - 10.63.255.255 defined for America. Then you can check it like

| eval ip = "10.1.2.34", subnet = "10.0.0.0/10"
| eval AMERICAS = if (cidrmatch(subnet,ip), "OK", "NOK")

If your subnets are not exactly dived by suitable masks, you need to add needed smaller subnets and combine this if with several OR clauses.

r. Ismo 

0 Karma

ITWhisperer
SplunkTrust
SplunkTrust

If your subnets are in CIDR format, you can use the cidrmatch() function

0 Karma
Career Survey
First 500 qualified respondents will receive a $20 gift card! Tell us about your professional Splunk journey.
Get Updates on the Splunk Community!

Introduction to Splunk AI

How are you using AI in Splunk? Whether you see AI as a threat or opportunity, AI is here to stay. Lucky for ...

Splunk + ThousandEyes: Correlate frontend, app, and network data to troubleshoot ...

Are you tired of troubleshooting delays caused by siloed frontend, application, and network data? We've got a ...

Maximizing the Value of Splunk ES 8.x

Splunk Enterprise Security (ES) continues to be a leader in the Gartner Magic Quadrant, reflecting its pivotal ...