Add domain to a subdirectory in side another domain

[vnmarser]

Hi all, I have a question needing your help.
I have a domain like abc.com (path: /root_path/abc.com/httpdocs/)
I installed a forum to access by abc.com/forum (path: /root_path/abc.com/httpdocs/forum/)
It means forum is a subdir of abc.com.

I have another domain xyzforum.com, and now I want to park or add-on (I'm not sure) to abc.com/forum where user access xyzforum.com, they will do not know that it is abc.com/forum.
e.g. http://abc.com/forum/newthread.php?do=newthread&f=88 should be the sames as http://xyzforum.com/newthread.php?do=newthread&f=88

My VPS is running with CentOS 5 and Plesk Control Panel. Can anyone help me to do this?

[JPC-Asif]

Yes it would be same, Multihosting basically shows the contents of the subdomain folder but hiding the actual URL like yourdomain.com/abc.com, Instead you can use any good domain name for this subdomain URL. But it is the same thing in any case :)

[vnmarser]

there are 3 options for hosting type I found in the Plesk Panel:

Physical hosting
Standard forwarding
Frame forwarding

1st one is not that.
I have tried both Standard forwarding and Frame forwarding, but the result did not meet my requirement.

As for Standard forwarding: when users go http://xyzforum.com, address is replaced with http://abc.com/forum/
As for Frame forwarding: the address is not replaced by http://abc.com/forum/ but when users click a link within site, there is no change in address bar. When mouse over a link, browsers still show the original link (something like http://abc.com/forum/newthread.php?do=newthread&f=88, NOT http://xyzforum.com/newthread.php?do=newthread&f=88 )

How can I do now? I know Cpanel can do this but I don't know how to do with Plesk.

[jason]

With frame forwarding the destination site is wrapped in an HTML frame so that the end user won't see the actual address of the content. This approach is pretty useless, IMHO. First, it confuses users because they never see the actual page address, it is bad for bookmarking because lots of browsers (older ones especially) have trouble bookmarking framed pages, and it is bad for search engines becasue the engines will index the content of the frame without reference to the frame, so people searching for you will see the address you are masking and not the one you want them to use.

Why not create a new site for the domain you want to multihost and move the forum to it? You could then do a 301 redirect (which would seamlessly send anyone following old bookmarks to the new address and notify search engines to update their indexes to point to the new location.

I am not a Plesk user, so I don't know how Plesk handles multihosted domains. If you don't want to move the site like I just suggested and you are comfortable with the server command line you could probably create a new domain in Plesk, delete the home directory for that domain, and create a hard link to the other domain's root in its place. As far as the OS is concerned, everything wold work as if there were two directories (or two sites) with the same content. Of course, any time you start messing with things the control pannel originally created you run the risk of it reverting things back, though in this case I see no reason why that would happen.

From the issue of search engine ranking, however, I would recommend my first suggestion. Having "duplicate content" (multiple addresses pointing at the same content) can hurt your rankings because hits, backlinks, etc. will be shared between all of them. Redirecting everything (with a 301 "permanent" redirect) will eliminate this problem.

--Jason