Configure Secondary MCN in SD-WAN High Availability

Instructions

1. Install the license and configure the management IP on the device you want to make as Secondary MCN. Both appliances in an HA pair must be the same appliance model.
2. After that, no further configuration is required on the Secondary MCN until we import the configuration package created on the Primary MCN.
3. Rest of the configuration would be done on the Primary MCN as in the case of adding Client sites.
4. On the Primary MCN, go under configuration editor and select one of the configuration files you want to edit.
5. To configure Secondary MCN device, you do not need to add another site
6. Please note that the "Secondary MCN" mode available under new site basic setting menu is for GEO MCN and not for SD-WAN same site HA configuration.
7. In the configuration editor, click on the Primary MCN site and click on High Availability option and then enable high availability as shown in the below image:
8. As shown in the above screenshot, give a name to the Secondary appliance and then enable/disable other checkbox options available as per your requirement. These options are not mandatory and are self-explanatory.
9. Now you will have to add HA IP Interfaces for the HA communication between the peer devices. You can use existing data interface to run HA or you can also configure a separate interface group for HA. In any case, you will have to configure unique Control IPs for HA communication between the peers. I have configured separate interface group for HA communication, to keep the control and data plane separate. If you want to use data interface for HA, you can skip the interface group configuration part shown below and go to step 13.
10. If you want to configure separate interface group for HA communication between the peers. Click on Apply in the HA configuration :
11. Then click on interface group settings under sites for the MCN and add separate interface group for HA and click apply. In the below example, I am using ethernet interface 2 for HA communication:
12. After interface group is configured, click on apply and then configure a virtual IP for the HA interface:

13. Once the virtual IP is configured for the HA interface, go back to the high availability options on the MCN and click on add HA IP Interface and select the HA virtual interface you want to use and also provide unique IPs for Primary and Secondary MCN in the same subnet as that of the Virtual IP address configured for the HA interface group. These IPs would be used for the HA peer communication and is different from the management IPs configured for device access.

14. Once the configuration is done, click on apply and save the new configuration package using save/save as option.
15. After saving the configuration, export it to the change management box by clicking on the export option:

16. Then go under Configuration >> Virtual WAN >> Change Management and click on Begin  :

17. Then click on Stage Appliances:

18. Once the staging begins, a new site would be created for the Secondary MCN:

19. Once staging is complete, click on Next and Activate Staged:

20. Once the activation is complete, download the active package for the new Secondary MCN HA site (created automatically) by clicking on the active link as shown below:

21. Once the package is downloaded, login to the GUI of the Secondary MCN using the management IP and go under configuration >> system maintenance >> Local Change Management and browse to the downloaded package for this site:

22. Click Upload and then Next, this will stage the configuration package:

23. Once the staging is done, click on Activate Staged:

24. After that, go under Configuration>>Virtual WAN >> Enable/Disable/Purge Flow and make sure that the Virtual WAN service is enabled. If not, then click on enable to enable the service. If the virtual WAN service is enabled, you would see the below screen:

25. The HA should be active and working now. You can confirm that by going under the Dashboard of management GUI on the Primary and Secondary MCN to see which device is Active and Standby in HA :
 

Status on Active MCN:

Status on Standby MCN: