Splunk Search

Save an 'eval'-based field extraction?

andyspusm
Explorer

I am extracting a field "ipaddr" which is the result of using "eval" to convert a previously extracted field "nwclient_ip_hex" (IP address in hexadecimal, for example "a0b0c0d0") to decimal. The snippet below works fine in the Search app.

How can I save "ipaddr" as a field so that other users of the app will be able to use it without needing all of that logic in the search bar?

... |eval d1 = tonumber(substr(nwclient_ip_hex,1,2),16) |eval d2 = tonumber(substr(nwclient_ip_hex,3,2),16) |eval d3 = tonumber(substr(nwclient_ip_hex,5,2),16) |eval d4 = tonumber(substr(nwclient_ip_hex,7,2),16) |eval ipaddr = d1+"."+d2+"."+d3+"."+d4

Thanks - Andy

0 Karma
1 Solution

gkanapathy
Splunk Employee
Splunk Employee

As of version 4.2.4, there is no way to do this. Search-time field extractions can only be simple substrings of the indexed data. You could encapsulate this logic in a macro, so the user sees less of the logic:

 ... | `convert_to_ip(nwclient_ip_hex)`

Where convert_to_ip() is defined as a macro that does the above. The user will still have to see the invocation of the macro, however.

View solution in original post

0 Karma

gkanapathy
Splunk Employee
Splunk Employee

As of version 4.2.4, there is no way to do this. Search-time field extractions can only be simple substrings of the indexed data. You could encapsulate this logic in a macro, so the user sees less of the logic:

 ... | `convert_to_ip(nwclient_ip_hex)`

Where convert_to_ip() is defined as a macro that does the above. The user will still have to see the invocation of the macro, however.

0 Karma

hulahoop
Splunk Employee
Splunk Employee

gkanapathy, any way to do this in 4.3 or 5.0?

0 Karma
Got questions? Get answers!

Join the Splunk Community Slack to learn, troubleshoot, and make connections with fellow Splunk practitioners in real time!

Meet up IRL or virtually!

Join Splunk User Groups to connect and learn in-person by region or remotely by topic or industry.

Get Updates on the Splunk Community!

Automating Threat Operations and Threat Hunting with Recorded Future

    Automating Threat Operations and Threat Hunting with Recorded Future June 29, 2026 | Register   Is your ...

Keep the Learning Going with the New Best of .conf Hub

Hello Splunkers, With .conf26 getting closer, there’s already a lot of excitement building around this year’s ...

Splunk Community Badges!

  Hey everyone! Ready to earn some serious bragging rights in the community? Along with our existing badges ...