Input field value: "this error occured for member123456. While making a payment of 60"
Desired input field value:"this error occured for member*. While making a payment of *"
If you're looking for a search time solution instead of index time, one option might be rex in sed mode.
<base search> | rex field=fieldname mode=sed "s|\d+|*|g"
Like this in props.conf on your HF/Indexer tier:
SEDCMD-obfuscate_membernumber_and_payment = s/this error occurred for member[^\.]\.\s+ While making a payment of \d+/this error occured for member\*\. While making a payment of \*/