The problem still exists, for 4.3.3-5ubuntu12.1 (Ubuntu 16.04). How to reproduce (using /etc/dhcp/dhcpd.conf installed from the package itself, without changes): 1. Starting with a fresh install: nornetpp@bjoernson:~$ sudo rm -rf /var/lib/dhcp /run/dhcp-server nornetpp@bjoernson:~$ sudo apt-get install --reinstall isc-dhcp-server Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not upgraded. Need to get 0 B/412 kB of archives. After this operation, 0 B of additional disk space will be used. Preconfiguring packages ... (Reading database ... 105366 files and directories currently installed.) Preparing to unpack .../isc-dhcp-server_4.3.3-5ubuntu12.1_amd64.deb ... Unpacking isc-dhcp-server (4.3.3-5ubuntu12.1) over (4.3.3-5ubuntu12.1) ... Processing triggers for systemd (229-4ubuntu7) ... Processing triggers for ureadahead (0.100.0-19) ... Processing triggers for man-db (2.7.5-1) ... Setting up isc-dhcp-server (4.3.3-5ubuntu12.1) ... insserv: warning: script 'screen-cleanup' missing LSB tags and overrides insserv: Default-Start undefined, assuming empty start runlevel(s) for script `screen-cleanup' insserv: Default-Stop undefined, assuming empty stop runlevel(s) for script `screen-cleanup' isc-dhcp-server start/running, process 24418 nornetpp@bjoernson:~$ apt-show-versions | grep isc-dhcp-server isc-dhcp-server:amd64/xenial-updates 4.3.3-5ubuntu12.1 uptodate isc-dhcp-server:i386 not installed 2. Starting the service fails: nornetpp@bjoernson:~$ sudo service isc-dhcp-server start isc-dhcp-server start/running, process 24553 nornetpp@bjoernson:~$ sleep 3 nornetpp@bjoernson:~$ sudo service isc-dhcp-server status isc-dhcp-server stop/waiting nornetpp@bjoernson:~$ tail -n20 /var/log/syslog.1 Aug 3 11:23:35 bjoernson dhcpd[24599]: process and the information we find helpful for debugging.. Aug 3 11:23:35 bjoernson dhcpd[24599]: Aug 3 11:23:35 bjoernson dhcpd[24599]: exiting. Aug 3 11:23:35 bjoernson dhcpd[24603]: Internet Systems Consortium DHCP Server 4.3.3 Aug 3 11:23:35 bjoernson dhcpd[24603]: Copyright 2004-2015 Internet Systems Consortium. Aug 3 11:23:35 bjoernson dhcpd[24603]: All rights reserved. Aug 3 11:23:35 bjoernson dhcpd[24603]: For info, please visit https://www.isc.org/software/dhcp/ Aug 3 11:23:35 bjoernson dhcpd[24604]: Internet Systems Consortium DHCP Server 4.3.3 Aug 3 11:23:35 bjoernson dhcpd[24604]: Copyright 2004-2015 Internet Systems Consortium. Aug 3 11:23:35 bjoernson dhcpd[24604]: All rights reserved. Aug 3 11:23:35 bjoernson dhcpd[24604]: For info, please visit https://www.isc.org/software/dhcp/ Aug 3 11:23:35 bjoernson dhcpd[24604]: Can't open /var/lib/dhcp/dhcpd.leases for append. Aug 3 11:23:35 bjoernson dhcpd[24604]: Aug 3 11:23:35 bjoernson dhcpd[24604]: If you think you have received this message due to a bug rather Aug 3 11:23:35 bjoernson dhcpd[24604]: than a configuration issue please read the section on submitting Aug 3 11:23:35 bjoernson dhcpd[24604]: bugs on either our web page at www.isc.org or in the README file Aug 3 11:23:35 bjoernson dhcpd[24604]: before submitting a bug. These pages explain the proper Aug 3 11:23:35 bjoernson dhcpd[24604]: process and the information we find helpful for debugging.. Aug 3 11:23:35 bjoernson dhcpd[24604]: Aug 3 11:23:35 bjoernson dhcpd[24604]: exiting. nornetpp@bjoernson:~$ sudo service isc-dhcp-server stop stop: Unknown instance: 3. Checking permissions, and setting them according to comment #7: nornetpp@bjoernson:~$ ls -al /var/lib/dhcp total 5 drwxr-xr-x 2 root root 112 Aug 3 11:22 . drwxr-xr-x 54 root root 1440 Aug 3 11:22 .. -rw-r--r-- 1 dhcpd dhcpd 125 Aug 3 11:22 dhcpd.leases -rw-r--r-- 1 root root 0 Aug 3 11:22 dhcpd.leases~ nornetpp@bjoernson:~$ sudo chmod 664 /var/lib/dhcp/*.leases nornetpp@bjoernson:~$ sudo chown root:dhcpd -R /var/lib/dhcp nornetpp@bjoernson:~$ sudo chmod 775 /var/lib/dhcp nornetpp@bjoernson:~$ ls -al /var/lib/dhcp total 5 drwxrwxr-x 2 root dhcpd 112 Aug 3 11:22 . drwxr-xr-x 54 root root 1440 Aug 3 11:22 .. -rw-rw-r-- 1 root dhcpd 125 Aug 3 11:22 dhcpd.leases -rw-r--r-- 1 root dhcpd 0 Aug 3 11:22 dhcpd.leases~ nornetpp@bjoernson:~$ nornetpp@bjoernson:~$ ls -al /run/dhcp-server total 0 drwxr-xr-x 2 dhcpd dhcpd 40 Aug 3 11:22 . drwxr-xr-x 31 root root 1260 Aug 3 11:22 .. nornetpp@bjoernson:~$ sudo chmod 775 /run/dhcp-server nornetpp@bjoernson:~$ sudo chown root:dhcpd -R /run/dhcp-server nornetpp@bjoernson:~$ ls -al /run/dhcp-server total 0 drwxrwxr-x 2 root dhcpd 40 Aug 3 11:22 . drwxr-xr-x 31 root root 1260 Aug 3 11:22 .. 4. Trying again (without success): nornetpp@bjoernson:~$ sudo service isc-dhcp-server start isc-dhcp-server start/running, process 24649 nornetpp@bjoernson:~$ sleep 3 nornetpp@bjoernson:~$ sudo service isc-dhcp-server status isc-dhcp-server stop/waiting nornetpp@bjoernson:~$ tail -n20 /var/log/syslog.1 Aug 3 11:24:38 bjoernson dhcpd[24695]: process and the information we find helpful for debugging.. Aug 3 11:24:38 bjoernson dhcpd[24695]: Aug 3 11:24:38 bjoernson dhcpd[24695]: exiting. Aug 3 11:24:38 bjoernson dhcpd[24699]: Internet Systems Consortium DHCP Server 4.3.3 Aug 3 11:24:38 bjoernson dhcpd[24699]: Copyright 2004-2015 Internet Systems Consortium. Aug 3 11:24:38 bjoernson dhcpd[24699]: All rights reserved. Aug 3 11:24:38 bjoernson dhcpd[24699]: For info, please visit https://www.isc.org/software/dhcp/ Aug 3 11:24:38 bjoernson dhcpd[24700]: Internet Systems Consortium DHCP Server 4.3.3 Aug 3 11:24:38 bjoernson dhcpd[24700]: Copyright 2004-2015 Internet Systems Consortium. Aug 3 11:24:38 bjoernson dhcpd[24700]: All rights reserved. Aug 3 11:24:38 bjoernson dhcpd[24700]: For info, please visit https://www.isc.org/software/dhcp/ Aug 3 11:24:38 bjoernson dhcpd[24700]: Can't open /var/lib/dhcp/dhcpd.leases for append. Aug 3 11:24:38 bjoernson dhcpd[24700]: Aug 3 11:24:38 bjoernson dhcpd[24700]: If you think you have received this message due to a bug rather Aug 3 11:24:38 bjoernson dhcpd[24700]: than a configuration issue please read the section on submitting Aug 3 11:24:38 bjoernson dhcpd[24700]: bugs on either our web page at www.isc.org or in the README file Aug 3 11:24:38 bjoernson dhcpd[24700]: before submitting a bug. These pages explain the proper Aug 3 11:24:38 bjoernson dhcpd[24700]: process and the information we find helpful for debugging.. Aug 3 11:24:38 bjoernson dhcpd[24700]: Aug 3 11:24:38 bjoernson dhcpd[24700]: exiting.