Using a custom domain for accessing umbraco

redirect

<!-- Restrict access to Umbraco -->
<rule name="Restrict access" stopProcessing="true">
    <match url="umbraco(?!/Surface/)" />
    <conditions logicalGrouping="MatchAny" trackAllCaptures="false">
        <add input="{HTTP_HOST}" matchType="Pattern" pattern="admin.example.com"
           ignoreCase="true" negate="true" />
    </conditions>
    <action type="Redirect" url="/not-found" appendQueryString="false" />
</rule>