[Kea-users] Duplicate logging

Sun Aug 9 16:04:33 UTC 2026

Hi Darren, you are correct that the [%c/%i.%t] pattern wasn't part of my 
logging, I went back to my earliest config file and didn't see it 
listed, not sure if the RHEL package had that changed or not by default, 
but I did just now add that to my pattern.

"loggers": [
     {
         "name": "kea-dhcp4",
         "output-options": [
             {
                 "output": "kea-dhcp4.log",
                 "pattern": "%D{%Y-%m-%d %H:%M:%S.%q} %-5p [%c/%i.%t] 
%m\n",
                 "maxsize": 150000000,
                 "maxver": 8
             }
         ],

         "severity": "INFO"
     },

Here is the updated logging I'm seeing:
2026-08-09 11:55:20.510 INFO  [kea-dhcp4.dhcp4/312252.139861619762880] 
DHCP4_QUERY_LABEL received query: [hwtype=1 b4:45:06:eb:25:69], 
cid=[01:b4:45:06:eb:25:69], tid=0xf908b62
2026-08-09 11:55:20.510 INFO  [kea-dhcp4.dhcp4/312252.139861628155584] 
DHCP4_QUERY_LABEL received query: [hwtype=1 b4:45:06:eb:25:69], 
cid=[01:b4:45:06:eb:25:69], tid=0xf908b62
2026-08-09 11:55:20.510 INFO  [kea-dhcp4.packets/312252.139861619762880] 
DHCP4_PACKET_RECEIVED [hwtype=1 b4:45:06:eb:25:69], 
cid=[01:b4:45:06:eb:25:69], tid=0xf908b627: DHCPINF.254 to 100.67.10.20 
on interface eno16895np0
2026-08-09 11:55:20.510 INFO  [kea-dhcp4.packets/312252.139861628155584] 
DHCP4_PACKET_RECEIVED [hwtype=1 b4:45:06:eb:25:69], 
cid=[01:b4:45:06:eb:25:69], tid=0xf908b627: DHCPINF.254 to 100.67.10.20 
on interface eno16895np0
2026-08-09 11:55:20.510 INFO  [kea-dhcp4.packets/312252.139861628155584] 
DHCP4_PACKET_SEND [hwtype=1 b4:45:06:eb:25:69], 
cid=[01:b4:45:06:eb:25:69], tid=0xf908b627: trying to s.67.10.20:67 to 
100.67.98.232:68 on interface eno16895np0
2026-08-09 11:55:20.510 INFO  [kea-dhcp4.packets/312252.139861619762880] 
DHCP4_PACKET_SEND [hwtype=1 b4:45:06:eb:25:69], 
cid=[01:b4:45:06:eb:25:69], tid=0xf908b627: trying to s.67.10.20:67 to 
100.67.98.232:68 on interface eno16895np0

As far as I can tell I only have one Kea process running on this server.
[root at 100671020-2 kea]# ps aux | grep kea
kea       312252  0.0  0.1 1832636 24524 ?       Ssl  11:55   0:00 
/usr/sbin/kea-dhcp4 -c /etc/kea/kea-dhcp4.conf
root      312828  0.0  0.0 227704  2260 pts/1    S+   12:01   0:00 grep 
--color=auto kea

Again, this happened suddenly with no changes to the system at that 
time.  My next step is to get a packet dump from what's reaching this 
server to see if somehow packets being sent are duplicated for some 
reason, that will be for Monday though.

On 2026-08-08 05:01, Darren Ankney wrote:
> Hi,
> 
> It won't be possible to help you with this without at least the
> loggers section of your configuration.  It also looks like you may
> have changed the logging pattern and did not include this part:
> "[%c/%i.%t]" which would have shown which logger was producing the
> log, the process id (to rule out the possibility of multiple Kea
> servers running), and finally the thread id (which would have been the
> final piece proving that it was the same log duplicated).
> Additionally, these values are often helpful when you are trying to
> trace what happened with a particular packet as they can move to
> different threads when parked during certain hook callouts and the
> like.  It is often helpful to organize the logs by thread id when
> looking deeply at some behavior.
> 
> Please attach a copy of your "loggers" configuration to progress
> troubleshooting.
> 
> Thank you,
> Darren Ankney
> 
> On Fri, Aug 7, 2026 at 4:10 PM Jim <jim at wrightthisway.com> wrote:
>> 
>> I don’t check my logs often but was making an update to my config and 
>> something odd caught my eye, I’m getting a number of lines duplicated. 
>>  My config hasn’t changed for months until today, and this started 
>> happening back in July 28, it looks like Kea reloaded itself and 
>> that’s when the dupes began.
>> 
>> I checked the logs and all I see is Version 3.0.3 listed both before 
>> and after that, so I don’t think the actual software release changed, 
>> yum shows my version as 3.0.3-1.el10_2.
>> 
>> Sample log lines that are dupes:
>> 
>> 2026-08-07 16:01:09.625 INFO  DHCP4_QUERY_LABEL received query: 
>> [hwtype=1 0c:29:ef:e2:05:80], cid=[no info], tid=0xd14ec51b
>> 
>> 2026-08-07 16:01:09.625 INFO  DHCP4_QUERY_LABEL received query: 
>> [hwtype=1 0c:29:ef:e2:05:80], cid=[no info], tid=0xd14ec51b
>> 
>> 2026-08-07 16:01:09.625 INFO  DHCP4_PACKET_RECEIVED [hwtype=1 
>> 0c:29:ef:e2:05:80], cid=[no info], tid=0xd14ec51b: DHCPDISCOVER (type 
>> 1) received from 100.67.122.254 to 100.67.10.20 on interface 
>> eno16895np0
>> 
>> 2026-08-07 16:01:09.625 INFO  DHCP4_PACKET_RECEIVED [hwtype=1 
>> 0c:29:ef:e2:05:80], cid=[no info], tid=0xd14ec51b: DHCPDISCOVER (type 
>> 1) received from 100.67.122.254 to 100.67.10.20 on interface 
>> eno16895np0
>> 
>> 2026-08-07 16:01:09.626 INFO  DHCP4_PACKET_SEND [hwtype=1 
>> 0c:29:ef:e2:05:80], cid=[no info], tid=0xd14ec51b: trying to send 
>> packet DHCPOFFER (type 2) from 100.67.10.20:67 to 100.67.122.254:67 on 
>> interface eno16895np0
>> 
>> 2026-08-07 16:01:09.626 INFO  DHCP4_PACKET_SEND [hwtype=1 
>> 0c:29:ef:e2:05:80], cid=[no info], tid=0xd14ec51b: trying to send 
>> packet DHCPOFFER (type 2) from 100.67.10.20:67 to 100.67.122.254:67 on 
>> interface eno16895np0
>> 
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