For any new or previously existing VPN cluster
that has more than one hub, in the Gateways window you must prioritize
the hubs to determine that traffic be sent to a particular hub and
to determine the subsequent hub failover order. A cluster supports
a maximum of four hubs. Select a hub and click in the Hub Failover
Priority field. Enter a priority (range is 1 to 4) of
the hub. The plugin internally maps the priority to a BGP
local preference value; the lower the priority value, the higher
the priority and local preference. - Priority 1 maps to
local preference 250.
- Priority 2 maps to local preference 200.
- Priority 3 maps to local preference 150.
- Priority 4 maps to local preference 100.
Multiple
hubs can have the same priority; an HA pair must have the same priority.
Panorama uses the branch’s BGP template to push the local preference of
the hubs to the branches in the cluster. If multiple hubs
in the cluster have the same priority, Panorama enables ECMP in
two places on each branch firewall to determine how branches select
the path. ECMP is enabled for the virtual router () and ECMP Multiple
AS Support is enabled for BGP (). If all hubs in the
cluster have a unique priority, ECMP is disabled on the branches. | 
