topic Re: Counting events based on IP Subnets in Splunk Search

Counting events based on IP Subnets

tsheets13 — Tue, 17 Mar 2020 14:04:26 GMT

I need to create a search to count the number of events in each geographic are of our network.

Each geo area will consist of multiple subnets.

Kentucky 10.10.10 10.10.11 10.10.12
Ohio 10.10.10.20 10.10.10.21
Indiana 10.10.30 10.10.31 10.10.32 10.10.10.33.

The report should simply output total by state:

Kentucky 112
Ohio 87
Indiana 212

All events have a full IP address but I've already used REX to assign the first 3 octets to the field SUBNET.

Thanks

tsheets13 — Tue, 17 Mar 2020 14:05:45 GMT

Sorry, typo,

Ohio should be 10.10.20 and 10.10.21

richgalloway — Tue, 17 Mar 2020 14:22:01 GMT

You could use a lookup table.

Define a lookup file ("subnets.csv") with two columns: subnet and state. Refer to the lookup file in your query.

<your current search> | lookup subnets.csv subnet OUTPUT state | stats count by state

rmmiller — Tue, 17 Mar 2020 14:24:46 GMT

You don't need to do any fancy regex to extract parts of the IP address. Make Splunk do the work with your lookup! 🙂

Hope that helps!
rmmiller

tsheets13 — Tue, 17 Mar 2020 14:24:57 GMT

So the lookup would contain 2 columns, subnet and state and nothing else correct?

rmmiller — Tue, 17 Mar 2020 14:57:37 GMT

Yes, for your application, you need to have 2 columns: subnet and state.

wmyersas — Tue, 17 Mar 2020 15:35:23 GMT

you can edit your question 🙂