On Splunk start up I see:
Undocumented key used in transforms.conf; stanza='anon' setting='DEST_KEY' key='raw'
Please resolve these problems by correcting typos in key names, or by adding them to [accepted_keys] in transforms.conf if they are intended.
All preliminary checks passed.
How can I run this check from the CLI? Is there some python script I can kick off?
This isn't exactly the answer to your question, but the btool utility can be useful for troubleshooting configuration files. See Use btool to troubleshoot configurations in the Troubleshooting Manual. There are other command-line troubleshooting tools, but I don't know of a command or tool that runs that check. Hopefully someone else will reply here with a more direct answer.
Yes, Im familiar with btool. Not exactly what Im looking for but thanks.