On 12/06/2017 10:07 AM, Pavel Zhukov via RT wrote:
> "Thomas Markwalder via RT" <dhcp-confidential@isc.org> writes:
>
>> Hello Pavel:
>>
>> We were able to reproduce it under Fedora 23.  Ubuntu and Centos 7
>> seem to be immune.  We have an alternative patch that is under review
>> and can forward it to you for testing once reviewed.
> Reproduced with Centos 7
> # rpm -q dhcp
> dhcp-4.2.5-58.el7.centos.x86_64
> # lsof | grep dhcpd | grep TCP | wc -l
> 191
> # omshell
>> server localhost
>> port 7911
>> connect
> dhcpctl_connect: no more
>
> Note: in case of virtual environment with virtio drivers and local to dhcpd
> traffic the issue is not reproducible.

AHA! Well done. Always better to have an logical explanation than not. 
Thank you for solving that.

Thomas