Is it ok to specify subdomains in certificates that support SAN.
For example base domain is example.com
and I want a.example.com
, b.example.com
, and c.example.com
to be included? What is the primary purpose of SANs?
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Mike Ounsworth
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user3448600
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1 Answers
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The purpose of SAN is to specify all host names for which a certificate can be used. This also includes any subdomains a certificate should be valid for, i.e. a certificate for example.com
will not be automatically valid for foo.example.com
but this subdomain must be explicitly specified as valid. Entries can also be wildcards. A proper implementation will no longer look at the common name at all if DNS names are given in the SAN section.
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Steffen Ullrich
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