Finding the MAC on the Adapter Card
Each Mellanox adapter card has a different identifier printed on the label: serial number and the card 
MAC for the Ethernet protocol.
MCX621102AC-ADAT Board Label Example MCX621102AN-ADAT Board Label Example 
MCX623102AC-ADAT Board Label Example MCX623102AN-ADAT Board Label Example
MCX623102AC-GDAT Board Label Example MCX623102AN-GDAT Board Label Example
The product revisions indicated on the labels in the following figures do not necessarily 
represent the latest revisions of the cards.