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Re: Verification config bien9

François TOURDE a écrit :
Pascal Hambourg écrivait:

NON ! Il vaut mieux éviter les CNAME autant que possible, surtout en
relation avec des NS ou MX.

Pour le NS, c'est clair, mais pour les MX, chezmoiçamarche(r) ...

Ça peut aussi ne pas marcher. C'est pourquoi cette pratique est déconseillée dans RFC 1912 - Common DNS Operational and Configuration Errors :

   Don't use CNAMEs in combination with RRs which point to other names
   like MX, CNAME, PTR and NS.  (PTR is an exception if you want to
   implement classless in-addr delegation.)  For example, this is
   strongly discouraged:

           podunk.xx.      IN      MX      mailhost
           mailhost        IN      CNAME   mary
           mary            IN      A

   [RFC 1034] in section 3.6.2 says this should not be done, and [RFC
   974] explicitly states that MX records shall not point to an alias
   defined by a CNAME.  This results in unnecessary indirection in
   accessing the data, and DNS resolvers and servers need to work more
   to get the answer.  If you really want to do this, you can accomplish
   the same thing by using a preprocessor such as m4 on your host files.

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