so by starting radiusd -X i have this error:
rlm_sql (sql): Driver rlm_sql_unixodbc (module rlm_sql_unixodbc) loaded and linked
rlm_sql (sql): Attempting to connect to sa@192.168.100.206:/radius
rlm_sql (sql): starting 0
rlm_sql (sql): Attempting to connect rlm_sql_unixodbc #0
rlm_sql_unixodbc: SQL down 08S01 [unixODBC][FreeTDS][SQL Server]Server is unavailable or does not exist.
rlm_sql_unixodbc: Connection failed
rlm_sql (sql): Failed to connect DB handle #0
rlm_sql (sql): starting 1
rlm_sql (sql): starting 2
rlm_sql (sql): starting 3
rlm_sql (sql): starting 4
rlm_sql (sql): Failed to connect to any SQL server
As you can figure out you have an connection error to your MS SQL DB. It is not a specificaly radius problem, it is only a misconfiurate db connection.
First of all, try to connect with the db with the isql progam.
Previously there is an aricle in this list about this: