In this scenario, the active source field is blank for the MAC address 00:0c:29:e8:b7:39, indicating an issue with how this MAC entry is being processed within the EVPN/VXLAN environment.
Step-by-Step Analysis:
* Understanding the MAC Entry:
* The active source field should normally indicate the source of the route advertisement for a specific MAC address within the EVPN. If it is blank, it suggests that there is a problem with how this entry is being learned or propagated.
* Possible Issues:
* Option A:If the EVPN route for this MAC address does not have a valid next hop, the entry might exist in the MAC table, but it will not have a valid path for forwarding, leading to a blank active source.
* Option B:If the ARP lookup had failed, the entry might not even appear in the MAC table.
However, the entry does exist, suggesting that ARP is not the primary issue here.
* Option C:If the host were locally connected, the active source should reflect a local interface, but the field is blank, ruling out local connection as the cause.
* Option D:Multicast EVPN routes typically do not appear in this manner in the MAC table, and this would not cause the active source to be blank.
Conclusion:The most logical explanation is that the EVPN route for this host exists but does not have a valid next hop, leading to the absence of an active source. This is consistent with how EVPN routing tables work in a VXLAN environment, where the lack of a valid next hop would prevent proper route advertisement and forwarding for the specific MAC address.