我有一台新创建的 Ubuntu 服务器，它运行良好，直到我应用了 SSL 证书（按照以下说明本网站）一切都运行正常，直到我尝试重新启动 appache，此时它失败了，并且 journalctl -xe 提供了以下内容：
Oct 25 09:25:47 moodle202320 sshd[26833]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=114.245.190.11 user=root
Oct 25 09:25:49 moodle202320 sshd[26833]: Failed password for root from 114.245.190.11 port 55434 ssh2
Oct 25 09:25:51 moodle202320 sshd[26833]: Connection closed by authenticating user root 114.245.190.11 port 55434 [preauth]
Oct 25 09:25:52 moodle202320 sudo[26837]: admin-moodle202310 : TTY=pts/0 ; PWD=/etc/ssh ; USER=root ; COMMAND=/etc/init.d/apache2 restart
Oct 25 09:25:52 moodle202320 sudo[26837]: pam_unix(sudo:session): session opened for user root by admin-moodle202310(uid=0)
Oct 25 09:25:52 moodle202320 systemd[1]: Starting The Apache HTTP Server...
-- Subject: A start job for unit apache2.service has begun execution
-- Defined-By: systemd
-- Support:
--
-- A start job for unit apache2.service has begun execution.
--
-- The job identifier is 12739.
Oct 25 09:25:52 moodle202320 apachectl[26847]: Action 'start' failed.
Oct 25 09:25:52 moodle202320 apachectl[26847]: The Apache error log may have more information.
Oct 25 09:25:52 moodle202320 systemd[1]: apache2.service: Control process exited, code=exited, status=1/FAILURE
-- Subject: Unit process exited
-- Defined-By: systemd
-- Support:
--
-- An ExecStart= process belonging to unit apache2.service has exited.
--
-- The process' exit code is 'exited' and its exit status is 1.
Oct 25 09:25:52 moodle202320 systemd[1]: apache2.service: Failed with result 'exit-code'.
-- Subject: Unit failed
-- Defined-By: systemd
-- Support:
--
-- The unit apache2.service has entered the 'failed' state with result 'exit-code'.
Oct 25 09:25:52 moodle202320 systemd[1]: Failed to start The Apache HTTP Server.
-- Subject: A start job for unit apache2.service has failed
-- Defined-By: systemd
-- Support:
--
-- A start job for unit apache2.service has finished with a failure.
--
-- The job identifier is 12739 and the job result is failed.
Oct 25 09:25:52 moodle202320 sudo[26837]: pam_unix(sudo:session): session closed for user root
Oct 25 09:25:52 moodle202320 sshd[26835]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=114.245.190.11 user=root
Oct 25 09:25:55 moodle202320 sshd[26835]: Failed password for root from 114.245.190.11 port 54526 ssh2
Oct 25 09:25:57 moodle202320 sshd[26835]: Connection closed by authenticating user root 114.245.190.11 port 54526 [preauth]
Oct 25 09:25:58 moodle202320 sshd[26860]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=114.245.190.11 user=root
Oct 25 09:26:00 moodle202320 sshd[26860]: Failed password for root from 114.245.190.11 port 54540 ssh2
Oct 25 09:26:00 moodle202320 sshd[26860]: Connection closed by authenticating user root 114.245.190.11 port 54540 [preauth]
Oct 25 09:26:02 moodle202320 sshd[26862]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=114.245.190.11 user=root
Oct 25 09:26:04 moodle202320 sshd[26862]: Failed password for root from 114.245.190.11 port 58644 ssh2
Oct 25 09:26:04 moodle202320 sshd[26862]: Connection closed by authenticating user root 114.245.190.11 port 58644 [preauth]
Oct 25 09:26:05 moodle202320 sshd[26866]: error: kex_exchange_identification: client sent invalid protocol identifier "-HSS2.0-PUTTY"
如果有人能解释一下问题是什么或者问题出在哪里，我会很感激，因为到目前为止我所做的一切都没有解决这个问题。
干杯。