Create a Pull Zone for the root domain (e.g. example.com) or subdomain (e.g. origin.example.com).

Create a CNAME DNS record that points your preferred subdomain (e.g. www.example.com) to your Zone URL (e.g. examplepull-hexid.kxcdn.com).

Add a Zone Alias for the subdomain created in step 2 (e.g. www.example.com).

From the KeyCDN dashboard, navigate to your Zone's settings. From here, configure the following settings:

1. Expire setting to 0
2. Ignore Cache Control setting to disabled
3. Forward Host Header setting to enabled
4. Strip Cookies setting to disabled
5. Canonical Header setting to disabled
6. Generic Error Pages setting to disabled

Modify your Nginx configuration file to resemble the following:

server {
    listen 80;

    # Use the Zone Alias added in step 3
    server_name www.example.com;

    location /ghost {
        proxy_hide_header Vary;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host $http_host;
        proxy_pass http://127.0.0.1:2368;
    }

    location / {
        proxy_hide_header Vary;
        proxy_hide_header Cache-Control;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host $http_host;
        proxy_pass http://127.0.0.1:2368;
    }
}

Configuring the above directives will disable any caching of the HTML document when file paths containing /ghost are accessed (e.g. Ghost admin). Additionally, setting proxy_hide_header Vary; and proxy_hide_header Cache-Control; will allow the HTML document to be cached for pages which do not contain /ghost.