# Hostnames and subdomains

The Hostnames table lists hosts stored on events. Empty until a hostname exists.

localStorage.cashline_vid is scoped to scheme + host + port. www.example.com and app.example.com do not share a visitor_id. Zarstat does not set a cookie on .example.com.

Host /cashline.js on the origin you measure (copy public/cashline.js, or load it from your Zarstat deploy). Collect posts to the script origin. That keeps the request first-party for that origin. It does not merge IDs across subdomains. There is no shared-subdomain proxy in this product.

HTML twin: https://www.zarstat.co.za/docs/hostnames