stumbled upon this old thread while googling.
we can at least show arp entries in CDOT 8.3.1:
> version
NetApp Release 8.3.1: Mon Aug 31 12:42:08 UTC 2015
> set diag
> network arp active-entry show
Node: node01
Vserver: Cluster
Subnet Group: 169.254.0.0/16
Remote IP Address MAC Address Port
----------------- ----------------- -------
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