Shared User Database - Experience & Questions

[gabs007]

Hi.

I'm seriously considering creating a master community and a smaller community which would share the same users on both websites. I've been reading it's easy between 2 or 3 IPS Communities. I have been also reading the technical information in the knowledgebase ( https://invisioncommunity.com/4guides/how-to-use-ips-community-suite/social-sign-in/43-and-above/connect-two-invision-communities-r297/). 
but I still have serious doubts and questions. 

 

If I create a slave and a master community sharing logins ? how many times is the user saved in the database ?  once for the master community  or both, one for the master and one for the slave community? 

If a member registers in the slave community ... is the user saved in the slave community only ? or saved in both communities ? or saved in the master community ? Where exactly is the user created, which database?

What happens to hte groups in the slave and master community ? Do both communities need to have similar groups? or exactly same groups ? or it doesn't matter.
The same with group promotions. IF I upgrade a member in the master community ? how does it affect the slave community ?

 

Thank you 

 

[bfarber]

The article you linked to outlines how you can share login information between two communities (or, more technically, allow a "master" community to authenticate a user in a "client" community).

This approach does not share any other information, including groups, custom profile field data, signature, etc. etc. A user will simply be able to log in to a "slave" (or a "client") installation using the same login credentials they use for the "master" (or "server") installation. This is exactly the same thing as when you go to a website and choose to login using Facebook, for instance, where you will be taken to Facebook's site, you log in, and are sent back to the website you started at.

A record will be stored in both the server and the client database (or master and slave, using your terminology).