Radius server retry with different secret

[Nicolas Goy]

On 03.08.20 06:20, Nicolas Goy wrote:
> (sorry for half message, I hit send by mistake)
> 
> Hello,
> 
> 
> 
> I am trying to implement a radius client, but I have an issue with server failover.
> 
> 
> I based my code on radius_example.c, and in this example, the auth message is build and sent only once.
> 
> 
> Now, if all failover servers have the same shared_secret, the failover works, but if they don't, the auth message needs to be rebuilt.
> 
> 
> In radius_client.c, there is a note about that:
> 
> 		/* Pending RADIUS packets used different shared secret, so
> 		 * they need to be modified. Update accounting message
> 		 * authenticators here. Authentication messages are removed
> 		 * since they would require more changes and the new RADIUS
> 		 * server may not be prepared to receive them anyway due to
> 		 * missing state information. Client will likely retry
> 		 * authentication, so this should not be an issue. */
> 
> 
> Now my question is: how can I be notified in my code that this occurred and that I need to rebuild the message and recall radius_client_send ?
> 
> Regards
> 


I ended up disabling radius_client.c built in multi server support and rolled my own retry logic. It's a bit less efficient as I reopen socket each time, but it works well.

-- 
Nicolas Goy

Programmer
https://www.kuon.ch

Goyman SA
https://www.goyman.com