LAMPs w/Wordpress with 3 domains. Two work as expected. One redirects to one of the others

Question

I have Mint 19.1; Apache 2.4; PHP 7.2; phpmyadmin, Wordpress 5.1.1 successfully installed and functioning.

• Site 1 Works as expected
• Site 2 Redirects to Site 1 without warning
• Site 3 Works as expected

The ONLY thing that appears to be different about Site 2, is that the TLD is .US vs .com

• I have site1.com in /var/www/site1.com/html
• I have site2.us in /var/www/site2.us/html
• I have site3.com in /var/www/site3.com/html

I have /etc/apache2/sites-available/ site1.conf, site2.conf and site3.conf files and those migrate to /etc/apache2/sites-enabled/ when I use A2ensite to enable each of the site conf files. I intend to migrate these to HTTPS once this is resolved.

Edit showing .conf files

Site 1

<VirtualHost *:80>  
   ServerName site1.com  
   Redirect permanent / https://site1.com/  
</VirtualHost>  

<VirtualHost *:443>  
        Header always set Strict-Transport-Security "max-age=63072000; includeSubDomains"  
        Header always append X-Frame-Options SAMEORIGIN  
        Header set X-XSS-Protection "1; mode=block"  
        ServerAdmin [email protected]  
        ServerName site1.com  
        ServerAlias www.site1.com  
        DocumentRoot /var/www/site1.com/html  
        ErrorLog ${APACHE_LOG_DIR}/error.log  
        CustomLog ${APACHE_LOG_DIR}/access.log combined  
        SSLEngine on  
        SSLCertificateFile  /etc/apache2/ssl/site1.com.crt  
        SSLCertificateKeyFile /etc/apache2/ssl/site1.com.key  
        SSLCertificateChainFile /etc/apache2/ssl/site1.com.intermediate.crt  
        SSLCipherSuite HIGH:!MEDIUM:!aNULL:!MD5:!RC4  
        SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire  
        <FilesMatch "\.(cgi|shtml|phtml|php)$">  
                SSLOptions +StdEnvVars  
        </FilesMatch>  
        <Directory /usr/lib/cgi-bin>  
                SSLOptions +StdEnvVars  
        </Directory>  
        <Directory /var/www/site1.com/html/>  
                AllowOverride All  
        </Directory>  
        RewriteEngine On  
        RewriteCond %{THE_REQUEST} !HTTP/1.1$  
        RewriteRule .* - [F]  
        ServerSignature Off  

</VirtualHost>  

Site2

<VirtualHost *:80>  
   ServerName site2.us  
   Redirect permanent / https://site2.us/  
</VirtualHost>  

<VirtualHost *:443>  
        Header always set Strict-Transport-Security "max-age=63072000; includeSubDomains"  
        Header always append X-Frame-Options SAMEORIGIN  
        Header set X-XSS-Protection "1; mode=block"  
        ServerAdmin [email protected]  
        ServerName site2.us  
        ServerAlias www.site2.us  
        DocumentRoot /var/www/site2.us/html  
    ErrorLog ${APACHE_LOG_DIR}/error.log  
    CustomLog ${APACHE_LOG_DIR}/access.log combined  
    SSLEngine on  
    SSLCertificateFile  /etc/apache2/ssl/site2.us.crt  
    SSLCertificateKeyFile /etc/apache2/ssl/site2.us.key  
    SSLCertificateChainFile /etc/apache2/ssl/site2.us.intermediate.crt  
    SSLCipherSuite HIGH:!MEDIUM:!aNULL:!MD5:!RC4  
    SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire  
    <FilesMatch "\.(cgi|shtml|phtml|php)$">  
            SSLOptions +StdEnvVars  
    </FilesMatch>  
    <Directory /usr/lib/cgi-bin>  
            SSLOptions +StdEnvVars  
    </Directory>  
    <Directory /var/www/site2.us/html/>  
            AllowOverride All  
    </Directory>  
        RewriteEngine On  
        RewriteCond %{THE_REQUEST} !HTTP/1.1$  
        RewriteRule .* - [F]  
        ServerSignature Off  

</VirtualHost>  

Site3

<VirtualHost *:80>  
   ServerName site3.com  
   Redirect permanent / https://site3.com/  
</VirtualHost>  

<VirtualHost *:443>  
        Header always set Strict-Transport-Security "max-age=63072000; includeSubDomains"  
        Header always append X-Frame-Options SAMEORIGIN  
        Header set X-XSS-Protection "1; mode=block"  
        ServerAdmin [email protected]  
        ServerName site3.com  
        ServerAlias www.site3.com  
        DocumentRoot /var/www/site3.com/html  
        ErrorLog ${APACHE_LOG_DIR}/error.log  
        CustomLog ${APACHE_LOG_DIR}/access.log combined  
        SSLEngine on  
        SSLCertificateFile  /etc/apache2/ssl/site3.com.crt  
        SSLCertificateKeyFile /etc/apache2/ssl/site3.com.key  
        SSLCertificateChainFile /etc/apache2/ssl/site3.com.intermediate.crt  
        SSLCipherSuite HIGH:!MEDIUM:!aNULL:!MD5:!RC4  
        SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire  
        <FilesMatch "\.(cgi|shtml|phtml|php)$">  
                SSLOptions +StdEnvVars  
        </FilesMatch>  
        <Directory /usr/lib/cgi-bin>  
                SSLOptions +StdEnvVars  
        </Directory>  
        <Directory /var/www/site3.com/html/>  
                AllowOverride All  
        </Directory>  
        RewriteEngine On  
        RewriteCond %{THE_REQUEST} !HTTP/1.1$  
        RewriteRule .* - [F]  
        ServerSignature Off  

</VirtualHost>  

** /var/www/site2.us/html/.htacess **

# BEGIN WordPress  
<IfModule mod_rewrite.c>  
RewriteEngine On  
RewriteBase /  
RewriteRule ^index\.php$ - [L]  
RewriteCond %{REQUEST_FILENAME} !-f  
RewriteCond %{REQUEST_FILENAME} !-d  
RewriteRule . /index.php [L]  
</IfModule>  

Answer 1

After clearing and rebooting the router and the cable modem, this odd behavior was eliminated. I presume the router was caching something incorrectly.