Ideally, you should never see terms like 'ifd' and 'ifl' in the logs but if you do see them in logs which look something like:
COSD_GENCFG_WRITE_FAILED: GENCFG write failed for Classifier to IFL 10. Reason: File exists
(ifd refers to physical interface and ifl refers to logical interfaces. One ifd can have multiple ifls under it. )
and you want to know which interface it is referring to, you can use the following hidden commands:
cli> show interfaces ifl-index 10
#In case it says ifd, you can use:
cli> show interfaces ifd-index 10