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To setup a CNAME you will need to edit the DNS record of your domain name. Add to your dns entry a CNAME that points to app.publitrac.com. Please make sure your DNS entry points to the domain app.publitrac.com and not an IP address. This will ensure your redirection keep working if the IP address changes.
For example, you could setup a CNAME redirect that isis offer.yourdomain.com that points to app.publitrac.com . The subdomain (bold portion) can be anything you wish.
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