Splunk Search

Why does Field extraction requires trim?

JarrettM
Path Finder

My iis data has a field name cs_uri_query, for example:

Cmd=Sync&User=XYZ%5Cjqpublic%40xyz.com&DeviceId=SEC539D6F312D5B3&DeviceType=SMG930V

Thusernameme is embedded in this field and I use the following regex to extract a new field called user_name:

^[^%]*%\d\w(?P\w+)

The new field is extracted properly and shows as:

user_name  = jqpublic

However, if I do a specific search like:

index=iis host=server1 user_name=jqpublic

I get no results.

Only if I trim the field, or use a wildcard, are results returned:

index=iis | eval user_name=trim(user_name) | search user_name=jqpublic

Any thoughts why trim is required here?

Thanks!

0 Karma

JarrettM
Path Finder

Yes that works, as does creating a calculated field that trims the extracted field. But what I want to know is why any of this is necessary. Why doesn't the original extraction work correctly?

Thanks!

0 Karma

493669
Super Champion

not sure which regex expression you are using...
It seems your extracted user_name field contains spaces so you need to trim...

0 Karma

493669
Super Champion

Hey have you tried this:

index=iis|rex "^[^%]*%\d\w(?P<user_name>\w+)"|search user_name="jqpublic"
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!

Mastering Threat Intelligence in ES 8.5, Splunk AI Assistant v2, and More from Splunk ...

Splunk Lantern is Splunk’s customer success center that provides practical guidance from Splunk experts on key ...

Break the Build: Inside the KubeDoom Lounge at .conf26

    You step up to the machine. The pixelated corridors of a certain 1993 FPS load in front of you, EMP Pulse ...

Splunk Auto Ingestion Parallel Pipeline Scaling

Why this feature matters Many Splunk environments experience ingestion pressure long before the host is fully ...