<AuthBy HASHBALANCE> distributes
RADIUS requests among a set of RADIUS servers so that multiple related
requests from the same user go to the same server unless that server
fails. This prevents the requests being distributed among multiple
servers, which is prone to problems with authentication methods that use
multiple messages, such as EAP.
When using <AuthBy
HASHBALANCE>, a hash number is calculated for each incoming
request. That hash number is based on number of attributes in the incoming
request. It is used to select which host to use. If the selected Host is
unavailable, then the next one on the Host list is used in sequence until
the Host list is exhausted. This results in a random distribution of
requests among the available server, and the same server handles all the
requests related to a single user.
The
HashAttributes parameter specifies which attributes
in the incoming request is used to select the server. The default value is
shown below. It is suitable for most use cases.
HashAttributes %{Request:Calling-Station-Id}:%n
