Hi - I had a similar issue with a large vol and CIFS share used to store documents, which hit the inode limit. From memory the only way we could see the issue, was when we logged on the CLI and looked at the system messages being generated and the warnings. System Manager wont alert you to it. DFM Operations Manager alerts you I believe, but this is a separate licensed product. I would possibly look at using PowerShell and the Data ONTAP cmdlets to see if there is one for the inodes, or one that can access/get the messages log and email you the output.
I use Operations Manager (Data Fabric Manager was the old name).
I have configured it to send alarms for such things as emails to me and our command center. For good measure I also have configured certain alarms to be to sent to me as SMS alerts using a SMS gateway provider on the internet.
For you inode problem, you would get a email like this:
A Warning event at 08 Jul 00:58 Romance Daylight Time on Volume XXvolumenameXX on Storage System XXstoragesystemnameXX
90.00% (87485891 out of total 97085638) inodes have been used up.