Wordpress 多站点子域名解析

Question

我有一个 Wordpress 多站点（我在 AWS 上的 Ubuntu 20.04 服务器上使用 Apache 2.4）。结构是一个主站点（例如 mainsite.com）和三个子域：

aaa.mainsite.com bbb.mainsite.com ccc.mainsite.com

一切正常，除了一个问题：aaa、bbb 和 ccc.mainsite.com 无法解析到各自的主页，而是解析到 mainsite.com 主页。但是，子域下的所有链接都可以正确解析：因此，例如 aaa.mainsite.com/somelink 可以转到正确的位置。

重要提示：此网站已从另一台服务器移出，之前它一直在那里运行。当我添加新的子域名时，它运行正常，但旧子域名仍然无法运行。

我有一个指向 mainsite.com 的 DNS A 记录，以及每个子域的记录，它们都正常工作，解析为我的服务器的 IP。我的 .htaccess 文件如下所示：

# BEGIN WordPress
# The directives (lines) between "BEGIN WordPress" and "END WordPress" are
# dynamically generated, and should only be modified via WordPress filters.
# Any changes to the directives between these markers will be overwritten.
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# uploaded files
RewriteRule ^files/(.+) wp-includes/ms-files.php?file=$1 [L]

# add a trailing slash to /wp-admin
RewriteRule ^wp-admin$ wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^(wp-(content|admin|includes).*) $1 [L]
RewriteRule ^(.*\.php)$ $1 [L]
RewriteRule . index.php [L]
# END WordPress

这是 VirtualHost 文件：

<IfModule mod_ssl.c>
<VirtualHost *:443>

        ServerAdmin webmaster@localhost
        ServerName mainsite.com
        ServerAlias *.mainsite.com
        DocumentRoot /var/www/mainsite
        DirectoryIndex index.php
        AddHandler type-map .var
        # Possible values include: debug, info, notice, warn, error, crit,
        # alert, emerg.

        # RewriteLog now deprecated
        LogLevel debug info warn

        <Directory var/www/mainsite>
                AllowOverride All
                Require all granted
        </Directory>

        Include /etc/letsencrypt/options-ssl-apache.conf
        SSLCertificateFile /etc/letsencrypt/live/mainsite.com/fullchain.pem
        SSLCertificateKeyFile /etc/letsencrypt/live/mainsite.com/privkey.pem

</VirtualHost>
</IfModule>
<VirtualHost *:80>

        ServerAdmin webmaster@localhost
        ServerName mainsite.com
        ServerAlias *.mainsite.com
        DocumentRoot /var/www/mainsite
        DirectoryIndex index.php
        AddHandler type-map .var
        # Possible values include: debug, info, notice, warn, error, crit,
        # alert, emerg.

        # RewriteLog now deprecated
        LogLevel debug info warn

        <Directory var/www/mainsite>
                AllowOverride All
                Require all granted
        </Directory>

        RewriteEngine on
        RewriteCond %{HTTPS} !=on
        RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

</VirtualHost>

有人知道我做错了什么吗？