[Kea-users] Dropping the packets in load balancing

[Peter Davies]

Hi Kraishak, 
Why would you want to stop the secondary HA server? What 
are you trying to achieve? 

In answer to your questions: 
1/2) When a HA server loses its connection to its partner, it starts a "failure 
detection" process. When the value of max-unacked-clients is not "0", the server 
uses the values of the "max-ack-delay" and "max-unacked-clients" to discover if 
it should take over processing its partner's clients' requests. 
Your settings are: 
"max-ack-delay": 10000, 
"max-unacked-clients": 13 

This means that after communication has been interrupted for "max-response-delay" 
(10000 milisecs), the primary will start the "failure detections" process. The 
process will wait until it has "seen" 13 DHCP packets that have a "secs" field 
with a value of 10000 or greater before starting to process the partners' client 
requests. 

see: https://kea.readthedocs.io/en/kea-2.3.7/arm/hooks.html#load-balancing-configuration 

3) There are commands to manipulate the state the servers are in. See the "host- 
ha-maintenance" commands at: 
https://kea.readthedocs.io/en/kea-2.3.7/arm/hooks.html#control-commands-for-high-availability 

But why would you want to do this? Supposing you want all client requests to be processed by 
one server and have the secondary active only when the primary is unavailable. In that case, 
you should consider using the "hot-standby" HA configuration. 

Kind Regards Peter 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.isc.org/pipermail/kea-users/attachments/20230510/086afa01/attachment-0001.htm>