AMC not accessible on secondary node after joining it to an existing 9.0.3 HA cluster
SonicWall has found an issue where the AMC on the slave node does not respond after joining it to an existing Cluster. This problem happens if the routing mode on the primary appliance (master node) is set to 'dual gateway' or 'single gateway-restricted'. If the master node is configured for dual gateway and when you join a node to the cluster, the default 0.0.0.0 route is calculated for the scondary interface on the slave box (which isn't configured yet).
This issue has been escalated to Engineering and the issue has been resolved in all future releases but as a workaround customer should change the routing mode under AMC -> Network Settings -> Routing from 'dual gateway' to 'single gateway-unrestricted' before adding a node to the cluster. More information on the routing mode can be found in the Admin Guide.