To add to what alemabrahao has said , Pinging from where to where and if using ping tools from the dashboard, which screen and tool?... Also you said your APs are in NAT mode, if it is NAT mode there is no way it can access the LAN. as the AP each run their own private 10.0.0.0/8 DHCP server for NAT with each AP having its default gateway of 10.128.128.128 and performing DHCP and for each client WIRELESSLY on the AP . Is it possible you just think you are pinging clients from a wired connection and are actually pinging other destinations on your LAN because your net uses Class A RFC 1918 on the LAN. See these docs: https://documentation.meraki.com/MR/Client_Addressing_and_Bridging/NAT_Mode_with_Meraki_DHCP https://documentation.meraki.com/MR/Client_Addressing_and_Bridging/SSID_Modes_for_Client_IP_Assignment#NAT_Mode
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