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免费通配证书

通配符证书允许您保护该域下的域和任何子域。如果您想保护现在或未来的example.org的任何子域名，则可以创建通配符证书。要生成通配符证书，请在域的开头添加一个星号，后跟一个句点。

通配符域不保护根域，因此如果您希望它也在一个证书下进行保护，则必须重新输入根域。例如，要为example.org创建通配符域，请输入*.example.org example.org

多个域或子域或通配符

允许多个域名或子域名，并且应该用空格分隔（例如“ subdomain.domain.com domain.com otherdomain.org * .wildcarddomain.com ”）。如果多个域或子域属于多个目录，则必须使用手动HTTP验证并将验证文件上传到正确的目录或使用DNS验证。

防止WWW被添加

如果尚未添加大多数用户需要的内容，我们会自动添加该域的www版本。要删除www，只需提交您想要验证的域名，然后在验证页面上点击“添加/编辑域名”顶部，然后删除并重新提交。

原文

Free Wildcard Certificates
Wildcard certificates allow you to secure a domain and any subdomains under that domain. If you wanted to secure any subdomains of example.org that you have now or in the future you can make a wildcard certificate. To generate wildcard certificates add an asterisk to the beginning of the domain(s) followed by a period. Wildcard domains do not secure the root domain so you must re-enter the root domain if you want it also secured under one certificate. For example to create a wildcard domain for example.org enter *.example.org example.org. To create a wildcard certificate for multiple domains such as example.org and example.com enter *.example.org example.org *.example.com example.com. Manual DNS verification will be required.

Multiple Domains or Subdomains or Wildcards
Multiple domains or subdomains are allowed and should be separated by spaces (e.g. "subdomain.domain.com domain.com otherdomain.org *.wildcarddomain.com"). If the multiple domains or subdomains pertain to multiple directories then you must use manual HTTP verification and upload verification files to the correct directories or use DNS verification.

Prevent WWW from being Added
We automatically add the www version of the domain if not already added as most users want that implicitly. To remove the www just submit the domains you want to verify then on the verification page near the top click on "Add / Edit Domains" and remove it and submit again.