我正在尝试在Apache服务器上安装自签名证书。首先，我做了
sudo a2enmod ssl
并获得以下输出：
Considering dependency setenvif for ssl:
Module setenvif already enabled
Considering dependency mime for ssl:
Module mime already enabled
Considering dependency socache_shmcb for ssl:
Enabling module socache_shmcb.
Enabling module ssl.
See /usr/share/doc/apache2/README.Debian.gz on how to configure SSL and create self-signed certificates.
To activate the new configuration, you need to run:
service apache2 restart
然后，我重新启动了apache2并收到以下错误：
(98)Address already in use: AH00072: make_sock: could not bind to address [::]:443
(98)Address already in use: AH00072: make_sock: could not bind to address 0.0.0.0:443
no listening sockets available, shutting down
AH00015: Unable to open logs
在 ports.conf 中，我有以下内容：
# If you just change the port or add more ports here, you will likely also
# have to change the VirtualHost statement in
# /etc/apache2/sites-enabled/000-default.conf
Listen 80
<IfModule ssl_module>
Listen 443
</IfModule>
<IfModule mod_gnutls.c>
Listen 443
</IfModule>
# vim: syntax=apache ts=4 sw=4 sts=4 sr noet
如果我对Listen 443内的<IfModule ssl_module>行发表评论，我就不会有任何错误。但是，这似乎让我无法听取443个请求。
我能做些什么才能听听443并且没有错误？