It looks like you have a problem with auth_basic for the /bitrix/admin/ path. I found some useful links that may help you:
[LIST][*]Restricting Access Using HTTP Basic Authentication - NGINX Documentation - Here you can learn how to create a file with usernames and passwords, how to configure the auth_basic and auth_basic_user_file directives, and how to combine basic authentication with IP address restriction.
[*]How to Setup HTTP Basic Authentication in NGINX - How-To Geek - Here you can find a step-by-step guide to setting up Basic Authentication for any path in nginx, as well as tips on using HTTPS/TLS and JSON Web Tokens.
[*]How to set up authentication in NGINX | Step by Step Guide - Here you can find a short and simple explanation on how to enable basic authentication in nginx.
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You may need to change the order of the location directives in your config file so that auth_basic applies to all files in /bitrix/admin/ and not just index.php. You can try the following option:
[CODE]location / { root /usr/local/www/site.ru;index index.php; error_page 404 = /404.php; }location ^~ /bitrix/admin/ { include inc/auth_basic; location ~ .php$ { fastcgi_pass unix:/tmp/site.sock; fastcgi_index index.php; include fastcgi_params; fastcgi_param SCRIPT_FILENAME /usr/local/www/site.ru/$fastcgi_script_name; fastcgi_param PHP_ADMIN_VALUE “sendmail_path = /usr/sbin/sendmail -t -i -f www@site.ru ”; fastcgi_ignore_client_abort off; } }location ~ .php$ { fastcgi_pass unix:/tmp/site.sock; fastcgi_index index.php; include fastcgi_params; fastcgi_param SCRIPT_FILENAME /usr/local/www/site.ru/$fastcgi_script_name; fastcgi_param PHP_ADMIN_VALUE “sendmail_path = /usr/sbin/sendmail -t -i -f www@site.ru ”; if (!-f $request_filename) { rewrite ^(.*)[/CODE]
