These are the IP addresses that may scan your server when it is listed on the website.

208.167.241.187
108.61.78.150
108.61.78.149
149.28.43.230
45.77.96.90

After you add the server to the website, it will generally be scanned from the same dedicated scanner. However, it is possible the queries can come from different scanners so we suggest ensuring all of these IPs are able to reach your server to prevent unintended time where the server is listed as "Offline".