I am setting up a DHCP server running on my wireless interface.
During boot the following messages show up in /var/log/syslog:
Nov 28 07:56:48 pi-w isc-dhcp-server[503]: Launching IPv4 server only.
Nov 28 07:56:51 pi-w isc-dhcp-server[503]: Starting ISC DHCPv4 server: dhcpdcheck syslog for diagnostics. ... failed!
Nov 28 07:56:51 pi-w isc-dhcp-server[503]: failed!
Nov 28 07:56:51 pi-w systemd[1]: isc-dhcp-server.service: Control process exited, code=exited, status=1/FAILURE
Nov 28 07:56:51 pi-w systemd[1]: isc-dhcp-server.service: Failed with result 'exit-code'.
/etc/default/isc-dhcp-server is:
# Defaults for isc-dhcp-server (sourced by /etc/init.d/isc-dhcp-server)
# Path to dhcpd's config file (default: /etc/dhcp/dhcpd.conf).
#DHCPDv4_CONF=/etc/dhcp/dhcpd.conf
#DHCPDv6_CONF=/etc/dhcp/dhcpd6.conf
# Path to dhcpd's PID file (default: /var/run/dhcpd.pid).
#DHCPDv4_PID=/var/run/dhcpd.pid
#DHCPDv6_PID=/var/run/dhcpd6.pid
# Additional options to start dhcpd with.
# Don't use options -cf or -pf here; use DHCPD_CONF/ DHCPD_PID instead
#OPTIONS=""
# On what interfaces should the DHCP server (dhcpd) serve DHCP requests?
# Separate multiple interfaces with spaces, e.g. "eth0 eth1".
INTERFACESv4="wlan0"
#INTERFACESv6=""
Excerpt from /etc/dhcp/dhcpd.conf:
subnet 192.168.1.0 netmask 255.255.255.0 {
range 192.168.1.50 192.168.1.115;
option subnet-mask 255.255.255.0;
option domain-name-servers 192.168.1.254, 10.128.254.254;
option domain-name “example.com”;
option routers 192.168.1.1;
}
wlan0 is set to a static IP in /etc/dhcpcd.conf:
interface wlan0
static ip_address=192.168.1.22/24
static routers=192.168.1.1
static domain_name_servers=127.0.0.1
static domain_search=
When I run sudo systemctl start isc-dhcp-server it is successful:
Nov 28 08:09:39 pi-w isc-dhcp-server[627]: Launching IPv4 server only.
Nov 28 08:09:41 pi-w isc-dhcp-server[627]: Starting ISC DHCPv4 server: dhcpd.
sudo systemctl status isc-dhcp-server.service:
● isc-dhcp-server.service - LSB: DHCP server
Loaded: loaded (/etc/init.d/isc-dhcp-server; generated)
Active: failed (Result: exit-code) since Sat 2020-11-28 17:18:15 PST; 1min 26s ago
Docs: man:systemd-sysv-generator(8)
Process: 474 ExecStart=/etc/init.d/isc-dhcp-server start (code=exited, status=1/FAILURE)
Nov 28 17:18:13 pi-w dhcpd[594]: bugs on either our web page at www.isc.org or in the README file
Nov 28 17:18:13 pi-w dhcpd[594]: before submitting a bug. These pages explain the proper
Nov 28 17:18:13 pi-w dhcpd[594]: process and the information we find helpful for debugging.
Nov 28 17:18:13 pi-w dhcpd[594]:
Nov 28 17:18:13 pi-w dhcpd[594]: exiting.
Nov 28 17:18:15 pi-w isc-dhcp-server[474]: Starting ISC DHCPv4 server: dhcpdcheck syslog for diagnostics. ... failed!
Nov 28 17:18:15 pi-w isc-dhcp-server[474]: failed!
Nov 28 17:18:15 pi-w systemd[1]: isc-dhcp-server.service: Control process exited, code=exited, status=1/FAILURE
Nov 28 17:18:15 pi-w systemd[1]: isc-dhcp-server.service: Failed with result 'exit-code'.
Nov 28 17:18:15 pi-w systemd[1]: Failed to start LSB: DHCP server.
sudo systemctl cat isc-dhcp-server.service:
# /run/systemd/generator.late/isc-dhcp-server.service
# Automatically generated by systemd-sysv-generator
[Unit]
Documentation=man:systemd-sysv-generator(8)
SourcePath=/etc/init.d/isc-dhcp-server
Description=LSB: DHCP server
Before=multi-user.target
Before=multi-user.target
Before=multi-user.target
Before=graphical.target
After=remote-fs.target
After=network-online.target
After=slapd.service
After=nss-lookup.target
Wants=network-online.target
[Service]
Type=forking
Restart=no
TimeoutSec=5min
IgnoreSIGPIPE=no
KillMode=process
systemctl status isc-dhcp-server.serviceandsystemctl cat isc-dhcp-server.service.systemctl status isc-dhcp-server.serviceandsystemctl cat isc-dhcp-server.serviceto my questionAfter=networking is started. Yes, it is and it is started in SysV emulation mode (shown in the first lines of the status). Emulation mode makes it more error prone. The problem is thatdhcpdis very uncommunicative about errors. I'm just looking to set debug output. The-doption cannot be used because the daemon isn't forked to the background then (Type=forking, required for systemd emulation).