Modify authentication order and authorization information for your appliance.

The data to POST contains aaa, radius and tacacs objects. aaa object includes auth_method and author objects. auth_method represents Authentication Order and author represents Authorization information.
Silver Peak recommends to use either RADIUS or TACACS+, but not both. For Authetication Order, configure the following:
First = Local
Second = either RADIUS or TACACS+. If not using either, then None.
Third = None.

When using RADIUS or TACACS+ to authenticate users, configure Authorization Information as follows:
Map Order = Remote First
Default User = admin.

For radius and tacacs object, Schema consists of a server object and a hash map of RADIUS/TACACS settings keyed by their order. You will need to construct an object of form: { 'server': { '1': {schema} }, { '2': {schema}} } for each object for POST operation to work and can configure a max of 3 RADIUS/TACACS servers. You can try GET operation for complete details of the schema.