Changes to the UnifiOS have meant that WAN ping does not work any more. You can enable this on the UDM by going into Firewall & Security in the UDM Network Settings. Create a new rule called “Echo Reply” in Internet Local and select “ICMP” for IPv4 Protocol and “Echo Reply” for IPv4 ICMP Type Name. Leave all other settings as default and ensure that Rule Applied shows “Before Predefined Rule”.
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