Splunk Search

How can I rex on an exact error code?

splgeek
Explorer

Hello ppl
I have a set of Error messages in an event log that looks like this
ERROR [43f796d8da] there are several codes like this in the events, so i don't want to miss out extracting them

What would be the rex command so that I could extract the Error codes and assign it to a field called Errortype?

0 Karma
1 Solution

gokadroid
Motivator

If the error code exists once in every log event then try these please:

1) If you want the ERROR word and square brackets in the string as well:

yourBaseSearch
| rex "(?<Errortype>ERROR\s\[[^\]]+\])"
| complete your query using Errortype field

See result here

2) If you only want only the code within the brackets, try:

yourBaseSearch
| rex "ERROR\s\[(?<Errortype>[^\]]+)\]"
| complete your query using Errortype field

See results here

View solution in original post

ehudb
Contributor
|rex "\w+\s\[(?<Errortype>[^\]]+)]"

Explanation:
A. Word with one or more letter
B. one or more space
C. starting bracket '['
D. One or more Non-Closing bracket ']' character (will be the field value)
E. Closing bracket ']'

0 Karma

gokadroid
Motivator

If the error code exists once in every log event then try these please:

1) If you want the ERROR word and square brackets in the string as well:

yourBaseSearch
| rex "(?<Errortype>ERROR\s\[[^\]]+\])"
| complete your query using Errortype field

See result here

2) If you only want only the code within the brackets, try:

yourBaseSearch
| rex "ERROR\s\[(?<Errortype>[^\]]+)\]"
| complete your query using Errortype field

See results here

Get Updates on the Splunk Community!

Application management with Targeted Application Install for Victoria Experience

  Experience a new era of flexibility in managing your Splunk Cloud Platform apps! With Targeted Application ...

Index This | What goes up and never comes down?

January 2026 Edition  Hayyy Splunk Education Enthusiasts and the Eternally Curious!   We’re back with this ...

Splunkers, Pack Your Bags: Why Cisco Live EMEA is Your Next Big Destination

The Power of Two: Splunk &#43; Cisco at "Ludicrous Scale"   You know Splunk. You know Cisco. But have you seen ...