Firstly, why are you using "CallDuration" as you text anchor in the regex when your sample show "TimeTaken"? Secondly, your JSON array has multiple entries, so, if you know how many entries (Stages)...
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Firstly, why are you using "CallDuration" as you text anchor in the regex when your sample show "TimeTaken"? Secondly, your JSON array has multiple entries, so, if you know how many entries (Stages) will be present, you can include that in your regex and extract each one separately, or you can use max_match=0 to extract them all into a multi-value field. Thirdly, for it to be valid JSON, there would be double quotes in the string which would need to be escaped in the regex. | rex field="_raw" max_match=0 "\"TimeTaken\": \"(?<hours>\d+)h:(?<minutes>\d+)m:(?<seconds>\d+)s\"" Fourthly, if it is JSON, why aren't you using spath to extract the fields (assuming you haven't extracted them as part of the sourcetype definition)?