We run into quite some customer cases about authentication failures related to KMS delegation token. It would be nice to see a log for each stage of the token:
3. removal upon cancel
4. remove upon expiration
So that when we correlate the logs for the same DT, we can have a good picture about what's going on, and what could have caused the authentication failure.
The same is applicable to other delegation tokens.
NOTE: When log info about delagation token, we don't want leak user's secret info.