La solution se trouve dans la kb50412 disponible chez NetApp : il faut exclure vos serveurs NetApp dans la configuration de votre proxy.

 Outils > Options Internet > Connexions > Paramétres réseau > Serveur Proxy >  Avancé > Exeption (renseignez le nom et l’addresse IP de vos baies Netapp)

=== DETAILS === API invoke failed.  Le serveur distant a retourné une erreur : (503) Serveur non disponible.

=== CORRECTIVE ACTION === No corrective action found

Solution ID: kb50412

Last updated: 21 AUG 2009 System Manager fails to load filer: (503) Server Unavailable

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Symptoms After installing NetApp System Manager and discovering one or more filers, clicking on the filer generates an error similar to:

API invoke failed. The remote server returned an error: (503) Server Unavailable.

A filer-based network trace will not show traces of HTTP connections, but only SNMP queries. This means that the HTTP request from the System Manager, which was obviously answered, was not answered by the filer.

  System Manager fails to load filer: (503) Server Unavailable

Cause of this problem The administrator workstations may have a proxy configured in its Internet settings. Since the System Manager queries the operating system for general settings, the HTTP traffic that carries the ONTAP-API-operations may be misguided towards a proxy which in this case replied unfavorable.

Solution Change your computer’s Internet settings to either:

Not use a proxy at all

-or- 

Have it explicitly exclude the Filer’s IP-addresses This way, System Manager can talk to the filers directly.

Environment    Data ONTAP 7G