Hello @RaphaelL,
The top table, "Allow listed snoop entries" is obtainable via API using the following call:
https://developer.cisco.com/meraki/api-v1/get-network-switch-dhcp-server-policy-arp-inspection-trust...
The bottom table, however, does not appear to have a specific API call. Network tab for browser developer tools also shows no API call is made for the bottom table when loading the page either.
That being said the data the bottom table contains can be found using the Network-wide > Monitor > Event log page. You could use https://developer.cisco.com/meraki/api-v1/get-network-events/ , use "includedEventTypes" to filter for "dai_blocked" events, and manipulate the returned data to obtain the same or similar information that the bottom table shows on Dashboard.
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