I've setup my nameservers, and made my main domain use it, it works fine.
When whm adds an acount it gives the acount this internal ip: 172.16.*.* .
This ip is set in the main setup of whm for Main Shared Virtual Host IP & ADDR-0 .
I suspect this is wrong, I tryd changing it to my main site's ip, but then the newly created domain just shows my main website.
Any idea to what I should change this to, or what else I should be changing?

p.s domains do work when I use servermatrix nameservers, together with mainip

172.x.x.x is the internal IP which SM uses to update your server. It will not work for you. Change it to one of the IPs which you are allocated, ie one of the 5 IPs which was assigned to you.

But.. when it's changed to my main ip it'll just show my main hosting site.. that's not good.

Or you mean change it in the main setup? Will it fix the acounts, or do they need some change aswell?
AND the strange thing is that an acount does work with my main ip if it uses sm's nameservers

Yes, in Server Setup, you most definitely need to change Main Shared Virtual Host IP: to one of the IP you are assigned.

And if you are using your own DNS server, you have to edit every single shared IP sites manually and change the pointed IP to the corrected shared IP.

If you are using SM's DNS then you make the changes in Orbit.

Then SSH into your machine and edit the httpd.conf file, change all the shared Ip to the corrected one. Restart BIND and Apache and it should work once everything is propagated.

If you are worried about seeing your main hosting site then ensure that the Shared IP is some other IP apart from your main one. There is no need to keep it the same as your main. You have 5 IPs to choose from.

* Main Shared Virtual Host IP changed to *.*.*.30
* ADDR-0 left to 172.16.*.*
* edited httpd.conf true ssh to change the newdomain.net to use *.*.*.30
* restarted bind succesfully
* restarted apache succesfully

* I also edited the dns zone in Whm for newdomain.net to use *.*.*.30 for newdomain.net (first two entries are ns1 & 2) and the ftp entry.

I hope I did ok

I believe ADDR-0 left to 172.16.*.*

should be set to your first IP. The reference should be to your server and not one of their internet IP.

Ok I did that aswell, but the thing when I changed newdomain.net to use *.*.*.30 in httpd.conf , is that good? Caus now it's just like newdomain.net has that dedicated ip / it's not free anymore

In /etc/httpd it's like this:
<VirtualHost *.*.*.30>

YES!!!!!
It is working thank you!

I am just wondering, if I go to *.*.*.30 it also shows the newdomain.net website. I asume this is not correct.

If someone types a numeric IP address, it will just redirect to the first site listed in httpd.conf for that IP address. There is nothing you could really do about it apart from adding another entry up at the top and have it refer to a default folder or something.

ok, thanks , didn't know that!

1 more question, I've setup a subdomain on my main domain, and every now and then people get a dns error for that subdomain; any idea why this is?

Note: Subdomains rely on the DNS system in order to function, which means that your DNS information must propagate throughout the different DNS servers on the Internet before your subdomain becomes fully active. This process on the average takes a few hours.