[Kea-users] kea 2.0.3 dhcp4 HA not working

[Peter Davies]

Hi -
    Thanks for the log files.

There isn't much to comment on here. Your HA configuration appears to be 
working.
HA Heartbeat commands are being sent and received correctly in both 
directions.
There are some HA warnings but they were generated on kea-1 before kea-2 
was up
and running, and on kea-2 after kea-1 had been shut down.

What I don't see is any dhcp traffic.

I suggest you let the servers run for a while and see what happens. If 
you can't
use live DHCP traffic you can use "perfdhcp" or "dhclient" to generate some.

For the secondary to start processing DHCPDISCOVERs the  HA parameters
"max-unacked-clients" and "max-ack-delay" are considered as well as the 
status of the primary.
The default value for the "max-ack-delay" parameter is 10000 milliseconds.
The default value of the  "max-unacked-clients"  parameter is 10.
see: 
https://kea.readthedocs.io/en/kea-2.0.3/arm/hooks.html#load-balancing-configuration

When you have your configuration working,  I  suggest you also consider 
enabling multi-threading.
see: 
https://kea.readthedocs.io/en/kea-2.2.0/arm/dhcp4-srv.html#multi-threading-settings

With multi-threading enabled, you can enable multi-threaded HA.
see: 
https://kea.readthedocs.io/en/kea-2.2.0/arm/hooks.html#multi-threaded-configuration-ha-mt

Multi-threaded HA creates a direct HA connection between the HA servers 
and does
not go through the control agent.

Kind Regards Peter


On 20/04/2023 19.13, vom513 wrote:
> FYI - I sent the below to the list with the 4 attachments but it’s awaiting moderator approval (total size was a bit above the limit).  If it doesn’t come through I will post these up somewhere http accessible.
>
>> On Apr 20, 2023, at 12:28 PM, Peter Davies <peterd at isc.org> wrote:
>>
>> Hi -
>>
>>    You have appended the kea-dhcp4 log from kea-2; it would be interesting to see the kea-dhcp4 and kea-ctrl-agent logs from kea-1 for the same time period.
>>
>> Do you think you could supply these?
> So I enabled DEBUG at 99 on kea-1/2, dhcp4/ca.  So 4 files total attached.  After a fresh restart of all daemons, after a bit, I did a "systemctl stop isc-kea-dhcp4-server isc-kea-ctrl-agent” on kea-1.
>
> Hopefully this will provide some clues as to what’s going on.  Let me know if you need more/different info.  And also thanks for helping with this so far.
>
>>
>> The last double quote in "memfile” is not a legal char.
>>
> I think this was from email formatting.  For good measure I replaced this character on both machines config files.

-- 
Peter Davies
Support Engineer
Internet Systems Corporation