The IP addresses used by eagle.io to connect to your devices can be obtained by examining the outgoing.eagle.io DNS record.
You can use the nslookup command line tool to resolve this host to the current set of server addresses, for example:
$nslookup outgoing.eagle.io
Non-authoritative answer:
Name: outgoing.eagle.io
Addresses: 54.253.77.113
54.252.235.152
13.54.238.139
3.104.245.239Note that addresses specified by the outgoing.eagle.io DNS record are likely to change over time, so this is best suited to firewalls that have the capability to specify a domain as part of a whitelist.
If this is not possible in your network environment, a better approach may be to restrict access using security features built into your device. For example, access to Campbell Scientific loggers can be restricted using the TCP Password/Encryption Key configuration options.