networking - Need help troubleshooting dhcpd during boot - Ask Ubuntu

i’m trying isc-dhcp-server working on headless ubuntu 14.04 machine , i’ve run problems documented in thread here. haven’t had response yet i’ve been trying different things , have more questions.

as indicated in other thread, can isc-dhcp-server working briefly. have ubuntu server connected router that’s configured dhcp server. once starts, shut off router’s dhcp service , re-start isc-dhcp-server service on ubuntu machine , begins giving out ip addresses in range configured, well. when reboot ubuntu machine however, dhcp service doesn’t come up. figured there may problem eth0 not being ready in time start of dhcpd service during boot sequence, wanted try booting without isc-dhcp-server service, leads first question:

how prevent isc-dhcp-server service starting on boot?

i’m running ubuntu 14.04, it’s not using upstart.

dpkg -s /sbin/init 

indicates:

systemd-sysv: /sbin/init 

i removed isc-dhcp-server init.d pgrep dhcpd shows it’s running when boot. how can be? other service start somehow? how can tell? syslog hasn’t helped me. did notice references in /etc/init.d/.depend.start , /etc/init.d/.depend.stop don’t know mean, example dnsmasq listed in files too, i’ve purged dnsmasq. (btw removed isc-dhcp-server.conf , isc-dhcp-server6.conf /etc/init)

as troubleshooting problem, decided try changing ip address of ubuntu machine 10.0.0.2 outside of dhcp range of router, modified /etc/network/interfaces:

# primary network interface auto eth0 iface eth0 inet static    address 10.0.0.200    netmask 255.255.255.0    network 10.0.0.0    broadcast 10.0.0.255    gateway 10.0.0.1 

ifconfig on ubuntu machine indicates 10.0.0.200 ip address assigned router still shows 10.0.0.2! can ssh ubuntu server using 10.0.0.2.

how can router show ip address ubuntu machine that’s different ifconfig reports?

troubleshooting tips welcome!