What is the purpose of the Overlay-ID?

rund · ‎02-09-2021

Hi,

if you are configuring a SD-WAN IOS-XE device there is an option to configure an overlay ID:

system
 system-ip             10.10.1.4
 overlay-id            1
 site-id               4
 port-offset           0
 control-session-pps   300
 admin-tech-on-failure
 sp-organization-name  MY_SP_ORGANISATION
 organization-name    MY_TENANT_ORGANISATION
 port-hop
 track-transport
 no track-default-gateway
 console-baud-rate     9600
 vbond 1.1.1.1 port 12346
!

Router(config-system)# overlay-id ?
Description: Overlay ID
Possible completions:
  <0..4294967295>[1]

The overlay ID also appears on "show sdwan omp peers":

Router#show sdwan omp peers
R -> routes received
I -> routes installed
S -> routes sent

                         DOMAIN    OVERLAY   SITE
PEER             TYPE    ID        ID        ID        STATE    UPTIME           R/I/S
------------------------------------------------------------------------------------------
10.10.1.2       vsmart  1         1         1         up       9:14:59:15       58/58/4

What is the purpose of the overlay ID?
How does it differ from the domain ID?
And how does it relate to the (tenant) organisation name?

Thanks a lot!

Mohamed Alhenawy · ‎02-13-2021

Hi @rund

- System-IP ----> It's Unique identifier of a SD-WAN component, It's 32-Bit (an IPv4 Address) Logically a VPN 0 Loop back Interface.

- SD-WAN overlay ID ----> It must match on all components of the fabric , It's look like **Domain** of the fabric.

- Site-ID –Identifies logical location of individual node, It is configured on every WAN Edge, When is not unique, same location is assumed.