How to Track Subdomains in One Sitemap

The Personalization tracking cookie can be shared across subdomains by setting the cookieDomain parameter to the main host domain. Here is an example for a retail company with multiple websites and subdomains in one dataset:

const getCookieDomain = () => {
    let currentDomain = window.location.hostname;
    if (currentDomain === "www.brandone.com.au") {
        return "brandone.com.au";
    } // All subdomains must use the same cookieDomain value
    else if (window.location.href.indexOf("brandtwo.com.au") > -1) {
        return "brandtwo.com.au"; 
    } 
};

const currentCookieDomain = getCookieDomain();
if (currentCookieDomain === "brandtwo.com.au" && (
    window.location.hostname === "brandtwo.com.au" ||
    window.location.hostname === "sub1.brandtwo.com.au" ||
    window.location.hostname === "sub2.brandtwo.com.au" ||
    window.location.hostname === "sub3.email.brandtwo.com.au")
) {
    SalesforceInteractions.init({
      cookieDomain: currentCookieDomain
    });
}