Network activate it. That’s all you do. Then it runs on the MAIN site.
If you want the Buddypress home base to be on a different site, you need to add a line in the wp-confgi.php file to tell it to do so.
define ( ‘BP_ROOT_BLOG’, $blog_id );
And replace $blog_id with the actual IDd number of the site you want it to run on.
Unfortunately, there’s no way to do this. If you activate it, it activates for all. Although, there’s been a lot of discussion and people interested in what you’re trying to do. Just no developer that’s stepped up ready to build it.
@techguy she also posted in the multisite forum. She only has one network, not looking for multiple. And she’s trying to have it show on a blog other than the main site.
Thanks for your help guys. I’m going to just have to figure out how to work it with the WP w/ BP as it’s own installation/database.
Hi all
I’m trying to do something similar to @mandi – I just set up a multisite installation, and wanted to have BP running on just one of the sub-sites, not the main one. From your reply, @andrea_r, it sounds like I need to update the wp-config file, but my question is: do you mean the wp-config file of the main site, or of the subsite that I want to run BP?
Will this mean that the other non-BP sites will behave like normal WP installations (i.e. so I can theme them independently, etc.)?
Thanks very much!
@JaffyDesigns there is only one wp-config.php per network/install which inlcudes the main site and subsites created from same install.
== other non-BP sites will behave like normal WP installations (i.e. so I can theme them independently, etc.)? ==
Yes, definitely.
Yep, I did some playing around, and figured that out, but definitely good to have my instincts confirmed. I’d been under the assumption that a multisite install actually replicated entire WP installs in different locations, so I was a little stumped – shows how new I am to multisite…thanks very much @mercime, appreciate the help!
For anyone else trying to achieve the same result, I found this article really useful: https://codex.buddypress.org/getting-started/install-buddypress-on-a-secondary-blog/
“I’d been under the assumption that a multisite install actually replicated entire WP installs in different locations, so I was a little stumped –”
the blog are virtual. 
A fact I keep repeating…
multisite background reading: wpmututorials.com
