问尝试通过SMTP发送邮件时出现mail错误

EN

intranet-worker     | mksp-worker  2021-07-30 07:49:39,693 INFO  mails.py:setup_mailserver Logging in to mail server "smtp.strato.de"
intranet-worker     | 07:49:39:   0.01s ! d8730ffa0ce644de9d5595cbe13290c8:send_welcome_mail failed, gaierror: [Errno -2] Name or service not known
intranet-worker     | Traceback (most recent call last):
intranet-worker     |   File "/usr/local/lib/python3.8/site-packages/arq/worker.py", line 525, in run_job
intranet-worker     |     result = await task
intranet-worker     |   File "/app/tasks/mails.py", line 106, in send_welcome_mail
intranet-worker     |     return await send_mail_to(user.email, tpl, values)
intranet-worker     |   File "/app/tasks/mails.py", line 50, in send_mail_to
intranet-worker     |     mail_server = await setup_mailserver()
intranet-worker     |   File "/app/tasks/mails.py", line 20, in setup_mailserver
intranet-worker     |     mail_server = smtplib.SMTP_SSL(settings.smtp_server, settings.smtp_port)
intranet-worker     |   File "/usr/local/lib/python3.8/smtplib.py", line 1034, in __init__
intranet-worker     |     SMTP.__init__(self, host, port, local_hostname, timeout,
intranet-worker     |   File "/usr/local/lib/python3.8/smtplib.py", line 253, in __init__
intranet-worker     |     (code, msg) = self.connect(host, port)
intranet-worker     |   File "/usr/local/lib/python3.8/smtplib.py", line 339, in connect
intranet-worker     |     self.sock = self._get_socket(host, port, self.timeout)
intranet-worker     |   File "/usr/local/lib/python3.8/smtplib.py", line 1040, in _get_socket
intranet-worker     |     new_socket = socket.create_connection((host, port), timeout,
intranet-worker     |   File "/usr/local/lib/python3.8/socket.py", line 787, in create_connection
intranet-worker     |     for res in getaddrinfo(host, port, 0, SOCK_STREAM):
intranet-worker     |   File "/usr/local/lib/python3.8/socket.py", line 918, in getaddrinfo
intranet-worker     |     for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
intranet-worker     | socket.gaierror: [Errno -2] Name or service not known

async def setup_mailserver():
    log.info('Logging in to mail server %s' % settings.smtp_server)
    log.debug('Going to use username %s for authentication' % settings.smtp_username)
    try:
        mail_server = smtplib.SMTP_SSL(settings.smtp_server, settings.smtp_port)
        mail_server.login(settings.smtp_username, settings.smtp_password)
        return mail_server

[user@hostname docker]$ docker-compose exec intranet-worker bash
root@cef64049ef54:/app# ping smtp.strato.de
PING smtp.strato.de (81.169.145.133) 56(84) bytes of data.
64 bytes from smtp.strato.de (81.169.145.133): icmp_seq=1 ttl=246 time=20.1 ms
64 bytes from smtp.strato.de (81.169.145.133): icmp_seq=2 ttl=246 time=20.2 ms
^C
--- smtp.strato.de ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 3ms
rtt min/avg/max/mdev = 20.113/20.169/20.226/0.152 ms