I'm trying to set up a wildcard subdomain on my VPS. Ultimately I want to end up with this:

main site: my.domain.tld
subdomain: sub1.my.domain.tld -> should end up serving my.domain.tld/sub1

I am using plesk 8.6. I have created a DNS A record pointing at my VPS' IP. I have then restarted the DNS server and waited up to 24 hours. But trying ping sub1.my.domain.tld results in an unknown host error.

So I know there's more stuff involved, configuring apache etc. But so far, I cannot even get the subdomain working at all, let alone serve up the right content.

I have also tried a CNAME record, to no effect. I have also tried creating a regular subdomain with a fixed name, which also does not work. Pre-configured subdomains DO work, like ftp.my.domain.tld or mail.my.domain.tld.

I am clearly missing something here, but my hosting provider charges a small fortune for any support request not involving hardware physically burning down, so I'm hesitant to ask them.

Any ideas?