Re: Selecting backend based on the user connecting

[Jesper Juhl]

Well, it seems to me that having shared mysql auth table compared to just having the proxy do the initial auth request and then assign server based on result could lead to a lot of different trouble.

- Whenever a new user is created it needs to be created on all backend servers instead of just the one holding the users database.

- Tools that connect to the DB servers and modify user accounts now need to be taught to do this on multiple servers (for example; our billing system connects to the db servers and disable user accounts if a customer has not paid his bills - and that's just one of many tools).

- Then there's the issue of the shared auth table growing very large on every db server. Not a problem for people with just a few hundred users, but potentially an issue with installations that have several orders of magnitude more users.

- New users are created all the time, existing users are modified, users are deleted etc etc. I would prefer to not have all the traffic associated with that hit all my db servers - which it would need if account details were to be updated everywhere.

- If I simply put the auth table at a shared location wouldn't it get corrupted pretty fast if several servers were operating on that shared file simultaniously?

If I can simply let all my existing apps connect to the proxy, let the proxy get the auth info and then send that session to the right backend server, then I can leave most of my existing infrastructure alone. All I have to do is split the users on several physical backend servers and each backend server is simple and self contained.