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It is also not new.
I want to install NBB in a subfolder on the same WP server. I intend on using WP as the Auth Provider, I also intend on using NBB for comments.
What would be the best practice folder for installation and why?
I suggest creating a new user on the system,
nodebb, complete with a home directory. Then, install your NodeBB forum under
/home/nodebb. This way, you need not worry about file permissions as long as you install and execute the forum with that user.
Can it be installed in a folder within wp-content?
I would not recommend doing this. Treat the two as entirely separate websites.
Will the SSO throw any redirect errors or can I just add mysite.com/forum as the auths Site URL?
It shouldn't care what domain you've set, as long as it is correct.
WP is using Apache, should I install NBB with Apache, or go with NGINX and leave WP using Apache?
To start with, I recommend putting Nginx in front of both Apache and NodeBB, as Nginx is the best supported reverse proxy that all of the core devs here use. Once you get everything working with that setup, you can experiment with using just Apache as your reverse proxy.
Thanks will give this a try.
Also considering having the WP site in an iframe on my NBB homepage, then styling both to match. However, with this option, I'm not sure how best to setup SSO. Is there a way to use NBB as Login, Registration and Profile and pass the info to WP. ie using NBB as the AUTH provider?