make a redirect from a sub-domain to main domain

Hello I need to do a redirect from an active blog installed in the sub-domain for the main domain I mounted a redirect from the sub to the main, the problem is the POSTs of this blog that are already indexed I want to redirect all URLs on the web to the default of the primary domain.

Redirect from sub to main works but urls from posts returns Not Found

    <rewrite>
  <rules>
    <rule name="BlogToPrincipal" stopProcessing="true">
      <match url="^(.*)$" />
      <conditions>
        <add input="{HTTP_HOST}" pattern="^blog\.meudominio\.com\.br$" />
      </conditions>
      <action type="Redirect" url="http://www.meudominio.com.br/{R:1}" redirectType="Permanent" />
    </rule>
  </rules>
</rewrite>