how rewrite all domains except some to root directory of specific domain

[se8820726]

I have a site called b.com now everyone come in and register in it I show him my NameServers and if he have any domain can set my nameservers on their domain.

I have another site on my server called a.com

now I want if anyone come in with his domain except a.com, apache send him to b.com root directory.

which file I must edit and what I must write in it ?

my webserver: apache
panel: directadmin

 

[se8820726]

why no one help me ??!!

 

[zEitEr]

Hello,

I'm not too sure what you are trying to achieve, probably you need to use redirects: http://site-helper.com/misc.html#redirect or mod rewrite rules.