Yes, NetApp Hardware Universe is your friend for these types of questions... check the "Onboard Ports & Cables" link in the results.
But be aware that the onboard ports on FAS8700 are reserved for internal use in most cases.
e0a/e0b (25GbE) are for HA cabling.
e0c/e0d (40/100GbE) are for cluster network cabling.
If you have the Ethernet bundle variant, the e0e -> e0h 10/25GbE Mezzanine ports can provide your connectivity for data or SnapMirror. If you have the FC bundle variant, you'll need to acquire suitable NICs for one of your PCIe slots.