Packet flow and encapsulation between VTEPs, provided I have a static tunnel ( just ipv4 address on each VTEP)

[networking_mat]

Q1. It would be really helpful to understand how the communication between VTEPs in a static tunnel works?

Q2. Is Manual VXLAN  supported  in cisco implementation? In case of Manual VXLAN, is there a need for multicast? 

From Juniper doc:

Manual VXLAN need to configure IGMP and PIM so that the switch can form the multicast trees for the VXLAN multicast groups. You must also configure each VTEP in a given VXLAN to be a member of the same mulcast

group.

The VTEPs can then forward ARP requests they receive from their connected hosts to the multicast group. The other VTEPs in the group de-encapsulate the VXLAN information, and (assuming they are members of the same VXLAN) they forward the ARP request to their connected hosts. When the target host receives the ARP request, it responds with its MAC address, and its VTEP forwards this ARP reply back to the source VTEP. Through this process, the VTEPs learn the IP addresses

of the other VTEPs in the VXLAN and the MAC addresses of the hosts connected to the other VTEPs.

3. In case of EVPN, what are the significance of Type 2 and Type 5 routes?

[Varun Jose]

1) Nexus 9000 switches support Static vxlan tunnels by a configuration called Static Ingress replication. Under the NVE interface, for the respective VNIs, you will need to mention the mode of replication(which is "ingress-replication protocol static") and then provide the remote VTEP IP addresses. it would look like below;

<snip>

vlan 144

 vn-segment 100144

interface nve1

 no shutdown

 source-interface loopback1

 member vni 100144

  ingress-replication protocol static

    peer-ip 192.168.100.100

</snip>

2) when static replication is used, there is no requirement for multicast as broadcast traffic like ARP requests are replicated statically to other VTEPs(unicast) and not multicast.

3) Type 2 routes are the ones which are used to exchange MAC/MAC-IP information with other VTEPs. so in short, if a new mac learn happens on a vtep for a vlan which is vxlan enabled, vtep will generate a type 2 mac advertisement and if layer 3 interface is configured for the vlan(SVI), and arp is complete, then the vtep would originate type 2 mac/IP advertisement. 

Type 5 routes are IP Prefixes which are originated by VTEPs. eg.  it could be a /24 or a /32 which is injected to fabric.