Can server break clients' cache settings?
Not with HyperText Transfer Protocol - the client always has the option to clear his or her cache and or otherwise ignore the Expires
/max-age
value and force a new request.
Is there any way (I guess not) to break the client's cache settings (even the homepage is cached)?
HTTP clients (I tested with FireFox) should ignore Expires
/max-age
cache headers when the domain name points to a new server.
Once you are back in control of the domain and the domain's A/AAAA records specify the IPv4/IPv6 address of a server which does not belong to the squatter, it should only be a matter of time (longer than you might like, but less than five years) before clients' cached DNS records are updated, their old cached content is ignored, and their requests return results from your server.
Test process:
- Specify IP address of Server #1 for "test.cache.domain" in hosts file
- Create virtual host, specify high-value max-age on Server #1
- Create virtual host, no cache-control headers on Server #2
- Request "test.cache.domain" in browser (review logs on Server #1 to confirm only one request)
- Close browser, clear local DNS cache, specify Server #2 IP address for "test.cache.domain" in hosts file
- Open browser and request "test.cache.domain" (should show results from Server #2)