@gioglifx: I have disabled all plugin except All In One Security & Firewall, but it still in WordPress Admin.
@mbrsolution: I have used easyengine when I setup my VPS, it uses Nginx web server. You may should install easyengine and test it. I have not used plugin cache and clear all cache service in my VPS.
Thank you very much.
Regards.
@mbrsolution You can logout like normal if the site that works, but it redirects me to a 404 page.
The site does not work as @gioglifx, it also redirect me to wp-login page, but when you type manually my-site.com you still work as an admin.
If I disable rename login page feature, it will work again.
I have the same problem. My new VPS is running nginx, but I use the same settings in another VPS is fine. I have deleted cache, tried a different browser.