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Set the Site URL/IP to the address of the Sitecore site where the S4S web services are installed. The address can be a URL with resolution through public DNS or an IP address. Optionally you may also include a port number, i.e. http://8.8.8.8:8000. Alternatively, this may use a Salesforce Named Credential by entering "callout:<Named_Credential_API_Name>".
If this is not a public facing website, you will need to ensure that a pinhole is open from Salesforce through to your IIS server, load balancer, CD/CM at the indicated IP or URL. See Salesforce Callouts.
If you require special HTTP headers to be sent with callouts, these can be entered in the Custom Headers field (Salesforce package v3.5 or greater). Include both the header name and value separated by a colon, e.g. "ApiKey:ABC123". If multiple headers are required enter one per line.
Authorise the URL by adding it to Remote Site Settings. If your site address already exists in the remote site setting list, you do not need to do this again. This step is not required when using a Named Credential.
Setup » Administer » Security Controls » Remote Site Settings (Salesforce Classic)
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