使用社区版docker镜像部署发送邮件失败,哪位大神知道是为什么

发送邮件提示一下错误:
[ERROR] seahub.api2.endpoints.admin.users:679 post [Errno -3] Temporary failure in name resolution
[ERROR] seahub.auth.views:357 password_reset [Errno -3] Temporary failure in name resolution

ping 一下这个域名看看可以通吗