Problem:

Will configuring the replication factor to 3 for three WAN interfaces transmit the packets to all the three WANs by default?


The requirement is to:

  • Send the original packet to WAN 1, 
  • First duplicate packet on the WAN 2, and 
  • Second Duplicate on the WAN 3.


How to configure for this?


Solution:

Yes, you can configure the replication factor 3 to transmit the packets to all the three WAN interfaces. 


The replication factor sends the first packet to WAN 1 and two copies of the packet to the other two WAN circuits.


Please check below link for more information about "Replication"

https://docs.versa-networks.com/Secure_SD-WAN/01_Configuration_from_Director/SD-WAN_Configuration/Advanced_SD-WAN_Configuration/Configure_Replication_for_SD-WAN_Traffic_Steering


Configure Replication:


By default, packet replication is disabled. To enable replication, you configure it when you configure an SD-WAN traffic-steering forwarding profile:


In Director view:


Select the Administration tab in the top menu bar.

Select Appliances in the left menu bar.

Select an appliance in the main panel. The view changes to Appliance view.

Select the Configuration tab in the top menu bar.

To configure a Layer 3 SD-WAN forwarding profile, select Services > SD-WAN > Forwarding Profiles in the left menu bar.

Click the add-icon-black-on-white.png Add icon. The Add Forwarding Profile popup window displays.




  1. add-forwarding-profile-general-tab-replication-border.png


Replication Factor


Enter the number of egress packets to send for each ingress packet. For example, if you configure a replication factor of 2, for each ingress packet, two egress packets (the original and one copy) are forwarded to the next hop.


If the replication factor you configure is greater than the number of paths available, only one copy of a packet is sent on the available alternate paths. For example, if you configure a replication factor of 3 and only two paths are available, the original packet is sent on the primary path and only one copy of the packet is sent on the alternate path. The packet is not sent twice on the alternate path. If three or more paths are available, the packet is sent on the primary link and two copies are sent on the alternate paths, so a total of three egress packets are sent for the one ingress packet.


Replication applies for a path, but not for a circuit or link. For example, if only one link is available on a hub and two links are available on a branch, the hub can reach both the branch links using the one link, effectively making two paths available from the hub to the branch. Here, replication happens on the same link, but the destination is reached on two different paths. However, if there is more than one link, the path on the alternate link is preferred over the path from the same link.