serverFault Question - https://serverfault.com/questions/891172/nginx-server-blocks-multiple-ssl-domains-lets-encrypt-certificates

gistfile1.txt

here is my main nginx.conf 
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user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

include /usr/share/nginx/modules/*.conf;

events {
    worker_connections 1024;
}

http {
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile            on;
    tcp_nopush          on;
    tcp_nodelay         on;
    keepalive_timeout   65;
    types_hash_max_size 2048;
    client_max_body_size 200M;

    include             /etc/nginx/mime.types;
    default_type        application/octet-stream;
    
    include /etc/nginx/conf.d/*.conf;

    server {
	listen       80 default_server;
        listen       [::]:80 default_server;
        server_name  A.B.C.D;
        root            /usr/share/nginx/html;
        index index.php index.html index.htm;

        # Load configuration files for the default server block.
        include /etc/nginx/default.d/*.conf;

        location / {
                try_files $uri $uri/ /index.html;
        }

       error_page 404 /404.html;
            location = /40x.html {
                root    /usr/share/nginx/html;
        }

	error_page 500 502 503 504 /50x.html;
            location = /50x.html {
                root    /usr/share/nginx/html;
        }

    location ~ .php$ {
                try_files $uri = 404;
                fastcgi_pass 127.0.0.1:9000;
                fastcgi_index index.php;
                fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
                include fastcgi_params;
        }

    }
}
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Here is my webappA.com nginx config, in /etc/nginx/conf.d/webappA.conf

server {
	listen       80;
        listen       [::]:80;
        server_name  webappA.com  www.webappA.com;
        root         /usr/share/nginx/html/webappA;
        index   index.php index.html index.htm;

        gzip on;
        gzip_http_version 1.0;
        gzip_disable "msie6";
        gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;

        location = /favicon.ico {
                log_not_found off;
                access_log off;
        }

	location = /robots.txt {
                allow all;
                log_not_found off;
                access_log off;
        }

	location / {
                try_files $uri /index.php?$query_string; # For Drupal >= 7
        }

        location @rewrite {
                rewrite ^/(.*)$ /index.php?q=$1;
        }

	error_page 404 /404.html;
            location = /40x.html {
                root /usrr/share/nginx/html/daniza;
        }

	error_page 500 502 503 504 /50x.html;
            location = /50x.html {
                root /usr/share/nginx/html/daniza;
        }

       location ~ .php$ {
                try_files $uri = 404;
                fastcgi_pass 127.0.0.1:9000;
                fastcgi_index index.php;
                fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
                include fastcgi_params;
        }

	location ~ ^/sites/.*/files/styles/ { # For Drupal >= 7
                try_files $uri @rewrite;

        }

	location ~ ^(/[a-z\-]+)?/system/files/ { # For Drupal >= 7
                try_files $uri /index.php?$query_string;
        }

        location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
                expires max;
                log_not_found off;
        }

	location ~* /(?:.+)/files/styles/adaptive/(?:.+)$ {
                if ( $http_cookie ~* "ais=(?<ais_cookie>[a-z0-9-_]+)" ) {
                        rewrite ^/(.+)/files/styles/adaptive/(.+)$ /$1/files/styles/$ais_cookie/$2 last;
                }
                access_log off;
                add_header X-Header "AIS Generator 1.0";
                set $nocache_details "Skip";
                try_files  $uri @drupal;
        }

        location ~* files/advagg_(?:css|js)/ {
                access_log off;
                expires max;
                add_header ETag "";
               	add_header Cache-Control "max-age=2628000, no-transform, public";
                try_files $uri $uri/ @rewrite;
	}

    listen 443 ssl; # managed by Certbot - This is fine! ssl_certificate omitted below
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configs for webappB.com in /etc/nginx/conf.d/webappB.conf - same as for webappA, with only changes in the server_name and root.