<header>Identifier verification</header>

This setting controls which domain names and IP addresses are included when
requesting a certificate from the ACME provider.

<ul>
<li><b>Request every identifier</b> submits all listed identifiers without a
preliminary DNS lookup. The entire request fails if the provider cannot
validate any one of them.</li>
<li><b>Skip unresolvable hostnames</b> performs an external DNS lookup first and
omits hostnames that do not resolve. IP addresses are not checked by this
lookup. The entire request still fails if the provider cannot validate any
remaining identifier.</li>
<li><b>Use only validated identifiers</b> allows the provider to omit identifiers
that it cannot resolve or validate and issue a certificate for the successful
subset.</li>
</ul><p>

The last option may produce a certificate that does not cover every requested
name or IP address. Correct the DNS or validation problem before relying on an
omitted identifier.

<footer>