Administrators can increase the security of external APIs for each site (subdomain) by whitelisting single IP addresses or IP address ranges. External API requests that come from an IP that isn’t on the whitelist will receive an Authorization has been denied for this request error message.
TIP
When no IP ranges are enabled, all IPs can access external APIs. Once one or more IP ranges are enabled, access to external APIs is restricted to those whitelisted IP addresses.

TIP
If you use a proxy server that does not truthfully report the original host’s IP address, you will need to add your proxy IP to the whitelisted range manually.
To add or edit a whitelisted IP range restriction:
> Customization > Integrations.
TIP
The To IP can be the same as the From IP if you only want to whitelist a single IP address
To disable a whitelisted IP range restriction:
To delete a whitelisted IP range restriction: