Why do I get a 421 Misdirected Request?

@FootballFan141

The only difference between the two configurations, other than the sub .vs. domain, is that in the sub you don’t have a directory configuration.

i.e.

        <Directory /var/www/blog/>
            Options Indexes FollowSymLinks
            AllowOverride All
            Require all granted
        </Directory>

So I would add that to the sub-domain as well (modified of course), for example:

        <Directory /var/www/testing/>
            Options Indexes FollowSymLinks
            AllowOverride All
            Require all granted
        </Directory>

… then restart Apache.

…

That being said, from doing a little digging, I stumbled across this –

When multiple vhosts share the same certificate, browsers will reuse an open connection for all those requests. mod_h2 currently only allows requests for the same host the connection was opened with. Some browsers throw then away the existing connection and open a new one. This can heavily impact performance.

So if that still holds true, then that’s the issue right there.

To remedy this, you’d need to generate independent SSL certificates, one for the primary domain and one for the sub-domain, instead of grouping them altogether in one certificate.

So if you’re using the older LetsEncrypt or the newer CertBot, you’d create one certificate passing:

-d animalcrossingcentral.com -d www.animalcrossingcentral.com

and then another, after the above is created, passing:

-d app.animalcrossingcentral.com -d www.app.animalcrossingcentral.com

You’d then modify the VirtualHost blocks to match the paths to the certificate and private key, then restart Apache again.

…

I didn’t really think of that as I primary use NGINX and it does not suffer from this odd limitation from what I’ve experienced (as I’ve grouped numerous sub-domains with a domain in the past).