I am building a network of sites, each one is a community with forums and will have other features.

Is it possible to have different sites running the same forum system (i.e. phpBB2) to draw from the same user base? What kind of modding/hacking would be required for this?

Would it mean installing all the sites into the same database, with different table headers. So instead of tables starting with phpbb2_ they would be "site1_" "site2_" "site3_" and so on? But then modify the code for the sites to all draw from site1_'s user tables?

I want it to be so that someone who registers with one site on the network, doesnt have to register to be a part of any other site on the network.

But at the same time, I want to be able to have different restrictions per site. So a user may be a moderator of one site, but a regular user on the others.

If this is possible, how much work would be estimated, and which forum/system would be best suited for this kind of situation?

I think you could do this relatively easily. Keep the same phpbb_user_group & phpbb_user for the 3 sites, then rename the rest of the tables. The longest part would probably be figuring out the install. I'm not sure how you would do it without overwriting the previous content in the database (if they aren't empty). It looks like you can change the table that php selects from in one file (but I can't find it). The SQL select commands have a variable. ie....

$sql = "SELECT *
FROM " . FORUMS_TABLE . "
WHERE forum_id = $forum_id";

Interesting idea by the way.

As a minimum you need "MySQL Standard" or "MySQL Pro". "MySQL Classic" is not a good idea. And it's a minimum.

Peter Kinev.

Would'nt you just need to change the server type to the IP address of the server and DB name, username, and password of the database you want to use?

I think this is what you are looking for:
"Multiple forums sharing a user database"
a article from phpBB website Knowlegde base::
http://www.phpbb.com/kb/article.php?article_id=55

Originally posted by dpny
I think this is what you are looking for:
"Multiple forums sharing a user database"
a article from phpBB website Knowlegde base::
http://www.phpbb.com/kb/article.php?article_id=55

Thanks! That is exactly what I was looking for.

now i'm off to go try it :)