Dell SmartFabric OS10 User Guide Release 10.5.4

Auto EVI Configuration mode

In this mode, an EVI is auto-allocated for each virtual network configured in the NVE.

The EVI Index is the same as the virtual network identifier.

The Route Distinguisher(RD) and the Route Target(RT) are also automatically generated as follows:

• The Route Distinguisher is Type 1 - derived from the overlay network source IP and the EVI index (Virtual-Network ID).
• The Route Target varies depending on the AS:
  • 2 byte AS: RT will be Type 0 derived from the 2 byte AS and the 3 byte VNI. (Type Encoded as 0x0002).
  • 4 byte AS: RT will be Type 2 derived from the 4 byte AS and the 2 byte EVI which is same as the virtual network ID that you have configured. (Type encoded as 0x0202)

This command is rejected if there are no BGP instances with EVPN address family enabled.

The Route target used for any given VNI needs to be identical on all VTEPs in order for EVPN to synchronize MAC addresses on all VTEPs.

In the case of 2 byte AS this is true for auto-derivation, since all the VTEPs are in the same AS and use the same VNI. In the case of 4 byte AS, the EVPN RFC recommends configuring manual Route target. However, SmartFabric OS10 switches support auto-derived Route targets even in case of 4 byte AS as follows:

• The Route target requires a 2 byte representation for each VNI.
• On SmartFabric OS10, the 2 byte representation for a VNI is its corresponding virtual network identifier.
• As long as the virtual network ID to VNI mapping is configured identical on all VTEPs, they will be able to use auto-derived Route targets even with 4 byte AS.

  switch(config)# evpn
  switch(config-evpn)# auto-evi

Explicit EVI Configuration mode

In this mode, an EVI is configured explicitly.

This mode allows User to configure Route Distinguisher and Route Targets explicitly.

switch(config)# evpn
switch(config-evpn)# evi 100

Auto configuration of RD and RT

The Route distinguisher is Type 1 - derived from the overlay network source IP and the user supplied EVI index.

The Route target is Type 2 - derived from the 4 byte AS and the user supplied EVI Index. (Type Encded as 0x0202).

switch(config)# evpn
switch(config-evpn)# evi 10
switch(config-evpn-evi-10)# rd   
A.B.C.D:[1..65535]  4-octet-ipv4addr:2-octet-number
  auto                Enable auto rd mode
switch(config-evpn-evi-10)# rd auto

switch(config)# evpn 
switch(config-evpn)# evi 10
switch(config-evpn-evi-10)# rd auto
switch(config-eqpn-evi-10)# route-target 
    {import | export | both} {<value>|auto}
switch(config-evpn-evi-10)# route-target both auto

Explicit configuration of RD and RT

switch(config)# evpn
switch(config-evpn)# evi 10
switch(config-evpn-evi)# rd   
A.B.C.D:[1..65535]  4-octet-ipv4addr:2-octet-number
  auto                Enable auto rd mode
switch(config-evpn-evi)# rd 111.111.111.111:65536


switch(config)# evpn 
switch(config-evpn)# evi 10
switch(config-evpn-evi-10)# rd 111.111.111.111:65535
switch(config-eqpn-evi-10)# route-target 
{import | export | both} {<value>|auto}
switch(config-evpn-evi-10)# route-target import 
  1..65535:1..4294967295  2-octet-asn:4-octet-number
  1..4294967295:1..65535  4-octet-asn:2-octet-number
  auto                    Enable auto route target mode
switch(config-evpn-evi-10)# route-target import 1:2
switch(config-evpn-evi-10)# route-target import 1:3 
  asn4  force 4-octet-asn:2-octet-number
switch(config-evpn-evi-10)# route-target import 1:3 asn4
switch(config-evpn-evi-10)# route-target export 1:4