Hi,
This is supported, but as per page 28 of the Best Practices for Virtual Port Channels (vPC) on Cisco Nexus 7000 Series Switches:
Note: If you are using a pure Cisco Nexus F1 Series system or VDC (that is, only F1 line cards used in the chassis or only F1 ports in the VDC), the peer-keepalive link can be formed with mgmt0 interface or 10-Gigabit Ethernet front panel port. In the latter case, use the management command under the SVI to enable it for inband management (otherwise, the SVI is brought down because no M1 modules exist in the system or VDC).
It's probably worth noting the recommendations as to how the peer-keepalive link should be configured:
Strong Recommendations:
When building a vPC peer-keepalive link, use the following in descending order of preference:
1. Dedicated link(s) (1-Gigabit Ethernet port is enough) configured as L3. Port-channel with 2 X 1G port is even better.
2. Mgmt0 interface (along with management traffic)
3. As a last resort, route the peer-keepalive link over the Layer 3 infrastructure
Regards
