To access domain before nameservers resolve,
I have a simple automated method for that.
Lets asume that your main domain is domain.xyz and the ip fior shared hosting is 18.104.22.168 on that server, then here is what you do:
– place in the dns of the main domain a new A record like this
*.s1.domain.xyz A 22.214.171.124
if you have more then 1 server then the next is *.s2.domain.xyz etc…
Then create a vhost.conf file in /home/httpd/vhosts/skel/0/conf with this line in it:
The @domain_name@ will be automaticly changed in by Plesk to the domainname that you add. So if you add test.com then the vhost.conf file will say test.com.s1.domain.xyz
This then automaticly creates a serveralias of the patern domain.your.server.name for every created domain on the server and because the wildcard is in your dns it will resolve the minute the domain is created (and apache is restarted).
.skel/0 is the default skel. If you use another default skel or clients use there own skel you will need to create the vhost.conf file there also. If you have more then 1 shared ip then you need to add more then 1 A record to the dns, 1 for every shared ip.