Beware VLAN double tagging!

In setting up some additional ESXi hosts in an aforementioned lab we ran into an issue where we could not communicate with the new hosts after setting static IPs and relevant management VLANs on them. The hosts are connected to 2 TOR switches (Cisco 9K Top Of Rack). Investigating on the switch you could see the hosts connected on the expected port on each switch (Ethernet 1/14 on each) by searching the mac address table for the relevant mac

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