FAQ-If MA5200G is configured with radius-server group, how to use weight and what is the principle of both algorithms of RADIUS

Publication Date:  2012-07-27 Views:  89 Downloads:  0
Issue Description
Q: If MA5200G is configured with radius-server group, it has two algorithms for working mode, including loading-share and master-backup, of which should be used? In loading-share, how to determine the load of each RADIUS server?

Alarm Information


Handling Process
Q: MA5200G RADIUS includes both working modes: 
                                2>master-backup (default)
Command radius-server algorithm could help revise the working mode of RADIUS server.
1. The principle of loading-share:  once MA5200G is configured with multiple radius-server ip, it could use all radius-server configured, and use the parameter of weight to allocate the traffic sent to radius-server, realizing loading-share;
For example: radius-server group radius
     radius-server authentication 2xx.142.211.7 1645 weight x
     radius-server authentication 2xx.142.211.8 1645 weight y
     radius-server authentication 2xx.142.211.9 1645 weight z
     radius-server accounting 2xx.142.211.7 1646 weight x
     radius-server accounting 2xx.142.211.8 1646 weight y
     radius-server accounting 2xx.142.211.8 1645 weight z

The per cent of weight of each server in total ratio is the traffic the server shares. For example, the server 2xx.142.211.7 accounts for x/(x+y+z)*100%, and 2xx.142.211.8 for y/(x+y+z)*100%, and so on; the formula is always available even more servers are configured. Weight does not mean the percent of loading-share. In fact, we suggest configuring the total of weight of all RADIUS servers to 100, so the weight value of each server is the per cent of load-sharing.

If one of the servers is down, MA5200G will allocate the traffic at the down server to other normal radius-servers.

2. master-backup is the default working mode of MA5200G radius-server, and its principle is when MA5200G is configured with multiple radius-servers, it could realize master-backup of radius-server. At this point, the weight is optional, being defaulted to 0.
For example:
 radius-server group radius
 radius-server authentication 2xx.142.211.7 1645 weight 0
 radius-server authentication 2xx.142.211.8 1645 weight 0
 radius-server accounting 2xx.142.211.7 1646 weight 0
 radius-server accounting 2xx.142.211.8 1646 weight 0

 MA5200G will take the server at the top (check by display radius-server configuration command)as the master RADIUS server, which serves for authentication and accounting generally; only if the master RADIUS fails, both authentication and accounting will turn to backup server. 

Root Cause