We get a lot of events in eventlog on an NBAR ID being blocked, but with no classification.
To lookup NBAR IDs, go to the protocol pack, and drill down the specific protocols to find out what ID it's using. You may download the PDF and search through it for the ID.
The protocol pack can be found here; NBAR Protocol Pack.
Some IDs that Meraki uses are not listed in the pdf.
Some of these are;
ID 2572 - Google Advertising.
ID 2619 - AppNexus
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