Job for isc-dhcp-server.service failed

Troubleshooting
1

So i am trying to set my pi up as a wifi hotspot however when i install the wifi hotspot software i get the following error.
i can see the wifi network on my phone it tries to connect to it but it just fails. any clue what could be going wrong or how to fix it?


Job for isc-dhcp-server.service failed because the control process exited with error code.
See "systemctl status isc-dhcp-server.service" and "journalctl -xeu isc-dhcp-server.service" for details.
invoke-rc.d: initscript isc-dhcp-server, action "start" failed.
× isc-dhcp-server.service - LSB: DHCP server
     Loaded: loaded (/etc/init.d/isc-dhcp-server; generated)
     Active: failed (Result: exit-code) since Wed 2023-06-28 11:56:20 BST; 63ms ago
 Duration: 4min 29.282s
       Docs: man:systemd-sysv-generator(8)
    Process: 2622 ExecStart=/etc/init.d/isc-dhcp-server start (code=exited, status=1/FAILURE)
        CPU: 100ms

Jun 28 11:56:18 DietPi dhcpd[2634]: bugs on either our web page at www.isc.org or in the README file
Jun 28 11:56:18 DietPi dhcpd[2634]: before submitting a bug.  These pages explain the proper
Jun 28 11:56:18 DietPi dhcpd[2634]: process and the information we find helpful for debugging.
Jun 28 11:56:18 DietPi dhcpd[2634]:
Jun 28 11:56:18 DietPi dhcpd[2634]: exiting.
Jun 28 11:56:20 DietPi isc-dhcp-server[2622]: Starting ISC DHCPv4 server: dhcpdcheck syslog for diagnostics. ... failed!
Jun 28 11:56:20 DietPi isc-dhcp-server[2622]:  failed!
Jun 28 11:56:20 DietPi systemd[1]: isc-dhcp-server.service: Control process exited, code=exited, status=1/FAILURE
Jun 28 11:56:20 DietPi systemd[1]: isc-dhcp-server.service: Failed with result ' exit-code'.
Jun 28 11:56:20 DietPi systemd[1]: Failed to start isc-dhcp-server.service - LSB: DHCP server.
Setting up hostapd (2:2.10-12) ...
Created symlink /etc/systemd/system/multi-user.target.wants/hostapd.service → /lib/systemd/system/hostapd.service.
Created symlink /etc/systemd/system/hostapd.service → /dev/null.
[  OK  ] DietPi-Software | APT install hostapd isc-dhcp-server iptables libnl-3-
2

Can you check please journalctl -u isc-dhcp-server.service.

3

you need to reboot your system once. This should bring up the service correctly.

4

i tried this and this is the log it produced

Jun 29 18:24:14 DietPi systemd[1]: Starting isc-dhcp-server.service - LSB: DHCP server...
Jun 29 18:24:14 DietPi isc-dhcp-server[582]: Launching IPv4 server only.
Jun 29 18:24:14 DietPi dhcpd[594]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 29 18:24:14 DietPi dhcpd[594]: Copyright 2004-2022 Internet Systems Consortium.
Jun 29 18:24:14 DietPi dhcpd[594]: All rights reserved.
Jun 29 18:24:14 DietPi dhcpd[594]: For info, please visit https://www.isc.org/software/dhcp/
Jun 29 18:24:14 DietPi isc-dhcp-server[582]: Starting ISC DHCPv4 server: dhcpd
Jun 29 18:24:14 DietPi isc-dhcp-server[596]: touch: cannot touch '/var/lib/dhcp/dhcpd.leases': Read-only file system
Jun 29 18:24:14 DietPi dhcpd[598]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 29 18:24:14 DietPi dhcpd[598]: Copyright 2004-2022 Internet Systems Consortium.
Jun 29 18:24:14 DietPi dhcpd[598]: All rights reserved.
Jun 29 18:24:14 DietPi dhcpd[598]: For info, please visit https://www.isc.org/software/dhcp/
Jun 29 18:24:15 DietPi dhcpd[598]: Can't open /var/lib/dhcp/dhcpd.leases for append.
Jun 29 18:24:15 DietPi dhcpd[598]:
Jun 29 18:24:15 DietPi dhcpd[598]: If you think you have received this message due to a bug rather
Jun 29 18:24:15 DietPi dhcpd[598]: than a configuration issue please read the section on submitting
Jun 29 18:24:15 DietPi dhcpd[598]: bugs on either our web page at www.isc.org or in the README file
Jun 29 18:24:15 DietPi dhcpd[598]: before submitting a bug.  These pages explain the proper
Jun 29 18:24:15 DietPi dhcpd[598]: process and the information we find helpful for debugging.
Jun 29 18:24:15 DietPi dhcpd[598]:
Jun 29 18:24:15 DietPi dhcpd[598]: exiting.
Jun 29 18:24:17 DietPi isc-dhcp-server[582]: check syslog for diagnostics. ... failed!
Jun 29 18:24:17 DietPi isc-dhcp-server[582]:  failed!
Jun 29 18:24:17 DietPi systemd[1]: isc-dhcp-server.service: Control process exited, code=exited, status=1/FAILURE
Jun 29 18:24:17 DietPi systemd[1]: isc-dhcp-server.service: Failed with result 'exit-code'.
Jun 29 18:24:17 DietPi systemd[1]: Failed to start isc-dhcp-server.service - LSB: DHCP server.

i also tried rebooting the pi and it still shows up as a network and i can enter the password but it tries to connect and just kinda times out after a bit

5

Let’s check permissions for that folder and it’s content:
ls -la /var/lib/dhcp/

EDIT:

It tried it on my RPI 3 B+ and it works flawlessly :thinking:
My ls -la /var/lib/dhcp/:

total 24
drwxr-xr-x  2 root root 4096 Jun 29 21:12 .
drwxr-xr-x 13 root root 4096 Jun 25 20:59 ..
-rw-r--r--  1 root root 1248 Jun 29 21:12 dhclient.eth0.leases
-rw-r--r--  1 root root  657 Jun 29 21:07 dhclient.wlan0.leases
-rw-r--r--  1 root root  631 Jun 29 21:13 dhcpd.leases
-rw-r--r--  1 root root  280 Jun 29 21:12 dhcpd.leases~
6

The file can’t be created as the file system is r/o indicating file system and data corruption

You can check for kernel error messages

dmesg -l 0,1,2,3
7

i get the exact same result as you when i check the permissions

when i check for the kernel errors i get this response

[ 27.705698] lan78xx 1-1.1.1:1.0 eth0: kevent 4 may have been dropped

note this is after a fresh install of the Os, i also saw that during the startup process the pi rapidly changes ip addresses to the point of about 1 every 3 seconds for like 5 minutes and that it sticks to 1

8

you need to check why you have a read only file system. This is not normal and usually indicating issues on your SD card.

9

how would i check for that i know my sd card itself is a read and writable sd card and it worked fine in the past

10

as root user, you can try following

touch /var/lib/dhcp/dhcpd.leases
11

it doesn’t respond with anything no errors or a different screen that pops up it just shows the command i just entered, even if i add sudo in front of it i get the same result

12 
systemctl restart isc-dhcp-server.service
journalctl -u isc-dhcp-server.service
13

when i entered the second command it stated that i have not configured a subnet yet so i assume this can be the issue? here’s the log from the command

Jun 30 09:19:13 DietPi dhcpd[2685]: No subnet declaration for eth0 (192.168.178.227).
Jun 30 09:19:13 DietPi dhcpd[2685]: ** Ignoring requests on eth0.  If this is not what
Jun 30 09:19:13 DietPi dhcpd[2685]:    you want, please write a subnet declaration
Jun 30 09:19:13 DietPi dhcpd[2685]:    in your dhcpd.conf file for the network segment
Jun 30 09:19:13 DietPi dhcpd[2685]:    to which interface eth0 is attached. **
Jun 30 09:19:13 DietPi dhcpd[2685]:
Jun 30 09:19:13 DietPi dhcpd[2685]:
Jun 30 09:19:13 DietPi dhcpd[2685]: Not configured to listen on any interfaces!
Jun 30 09:19:13 DietPi dhcpd[2685]:
Jun 30 09:19:13 DietPi dhcpd[2685]: If you think you have received this message due to a bug rather
Jun 30 09:19:13 DietPi dhcpd[2685]: than a configuration issue please read the section on submitting
Jun 30 09:19:13 DietPi dhcpd[2685]: bugs on either our web page at www.isc.org or in the README file
Jun 30 09:19:13 DietPi dhcpd[2685]: before submitting a bug.  These pages explain the proper
Jun 30 09:19:13 DietPi dhcpd[2685]: process and the information we find helpful for debugging.
Jun 30 09:19:13 DietPi dhcpd[2685]:
Jun 30 09:19:13 DietPi dhcpd[2685]: exiting.
Jun 30 09:19:15 DietPi isc-dhcp-server[2673]: Starting ISC DHCPv4 server: dhcpdcheck syslog for diagnostics. ... failed!
Jun 30 09:19:15 DietPi isc-dhcp-server[2673]:  failed!
Jun 30 09:19:15 DietPi systemd[1]: isc-dhcp-server.service: Control process exited, code=exited, status=1/FAILURE
Jun 30 09:19:15 DietPi systemd[1]: isc-dhcp-server.service: Failed with result 'exit-code'.
Jun 30 09:19:15 DietPi systemd[1]: Failed to start isc-dhcp-server.service - LSB: DHCP server.
Jun 30 09:19:54 DietPi systemd[1]: Starting isc-dhcp-server.service - LSB: DHCP server...
Jun 30 09:19:54 DietPi isc-dhcp-server[3117]: Launching IPv4 server only.
Jun 30 09:19:54 DietPi dhcpd[3126]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 30 09:19:54 DietPi dhcpd[3126]: Copyright 2004-2022 Internet Systems Consortium.
Jun 30 09:19:54 DietPi dhcpd[3126]: All rights reserved.
Jun 30 09:19:54 DietPi dhcpd[3126]: For info, please visit https://www.isc.org/software/dhcp/
Jun 30 09:19:54 DietPi dhcpd[3129]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 30 09:19:54 DietPi dhcpd[3129]: Copyright 2004-2022 Internet Systems Consortium.
Jun 30 09:19:54 DietPi dhcpd[3129]: All rights reserved.
Jun 30 09:19:54 DietPi dhcpd[3129]: For info, please visit https://www.isc.org/software/dhcp/
Jun 30 09:19:54 DietPi dhcpd[3129]: Wrote 0 leases to leases file.
Jun 30 09:19:54 DietPi dhcpd[3129]: Server starting service.
Jun 30 09:19:56 DietPi isc-dhcp-server[3117]: Starting ISC DHCPv4 server: dhcpd.
Jun 30 09:19:56 DietPi systemd[1]: Started isc-dhcp-server.service - LSB: DHCP server.
Jun 30 09:56:55 DietPi systemd[1]: Stopping isc-dhcp-server.service - LSB: DHCP server...
Jun 30 09:56:55 DietPi isc-dhcp-server[3461]: Stopping ISC DHCPv4 server: dhcpd.
Jun 30 09:56:55 DietPi systemd[1]: isc-dhcp-server.service: Deactivated successfully.
Jun 30 09:56:55 DietPi systemd[1]: isc-dhcp-server.service: Unit process 3129 (dhcpd) remains running after unit stopped.
Jun 30 09:56:55 DietPi systemd[1]: Stopped isc-dhcp-server.service - LSB: DHCP server.
Jun 30 09:56:55 DietPi systemd[1]: isc-dhcp-server.service: Found left-over process 3129 (dhcpd) in control group while starting unit. Ignoring.
Jun 30 09:56:55 DietPi systemd[1]: This usually indicates unclean termination of a previous run, or service implementation deficiencies.
Jun 30 09:56:55 DietPi systemd[1]: Starting isc-dhcp-server.service - LSB: DHCP server...
Jun 30 09:56:55 DietPi isc-dhcp-server[3473]: Launching IPv4 server only.
Jun 30 09:56:55 DietPi dhcpd[3483]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 30 09:56:55 DietPi dhcpd[3483]: Copyright 2004-2022 Internet Systems Consortium.
Jun 30 09:56:55 DietPi dhcpd[3483]: All rights reserved.
Jun 30 09:56:55 DietPi dhcpd[3483]: For info, please visit https://www.isc.org/software/dhcp/
Jun 30 09:56:55 DietPi dhcpd[3486]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 30 09:56:55 DietPi dhcpd[3486]: Copyright 2004-2022 Internet Systems Consortium.
Jun 30 09:56:55 DietPi dhcpd[3486]: All rights reserved.
Jun 30 09:56:55 DietPi dhcpd[3486]: For info, please visit https://www.isc.org/software/dhcp/
Jun 30 09:56:55 DietPi dhcpd[3486]: Wrote 0 leases to leases file.
Jun 30 09:56:55 DietPi dhcpd[3486]: Server starting service.
Jun 30 09:56:57 DietPi isc-dhcp-server[3473]: Starting ISC DHCPv4 server: dhcpd.
Jun 30 09:56:57 DietPi systemd[1]: Started isc-dhcp-server.service - LSB: DHCP server.
Jun 30 09:57:28 DietPi systemd[1]: Stopping isc-dhcp-server.service - LSB: DHCP server...
Jun 30 09:57:28 DietPi isc-dhcp-server[3493]: Stopping ISC DHCPv4 server: dhcpd.
Jun 30 09:57:28 DietPi systemd[1]: isc-dhcp-server.service: Deactivated successfully.
Jun 30 09:57:28 DietPi systemd[1]: isc-dhcp-server.service: Unit process 3486 (dhcpd) remains running after unit stopped.
Jun 30 09:57:28 DietPi systemd[1]: Stopped isc-dhcp-server.service - LSB: DHCP server.
Jun 30 09:57:28 DietPi systemd[1]: isc-dhcp-server.service: Found left-over process 3486 (dhcpd) in control group while starting unit. Ignoring.
Jun 30 09:57:28 DietPi systemd[1]: This usually indicates unclean termination of a previous run, or service implementation deficiencies.
Jun 30 09:57:28 DietPi systemd[1]: Starting isc-dhcp-server.service - LSB: DHCP server...
Jun 30 09:57:28 DietPi isc-dhcp-server[3505]: Launching IPv4 server only.
Jun 30 09:57:28 DietPi dhcpd[3514]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 30 09:57:28 DietPi dhcpd[3514]: Copyright 2004-2022 Internet Systems Consortium.
Jun 30 09:57:28 DietPi dhcpd[3514]: All rights reserved.
Jun 30 09:57:28 DietPi dhcpd[3514]: For info, please visit https://www.isc.org/software/dhcp/
Jun 30 09:57:28 DietPi dhcpd[3517]: Internet Systems Consortium DHCP Server 4.4.3-P1
Jun 30 09:57:28 DietPi dhcpd[3517]: Copyright 2004-2022 Internet Systems Consortium.
Jun 30 09:57:28 DietPi dhcpd[3517]: All rights reserved.
Jun 30 09:57:28 DietPi dhcpd[3517]: For info, please visit https://www.isc.org/software/dhcp/
Jun 30 09:57:28 DietPi dhcpd[3517]: Wrote 0 leases to leases file.
Jun 30 09:57:28 DietPi dhcpd[3517]: Server starting service.
Jun 30 09:57:30 DietPi isc-dhcp-server[3505]: Starting ISC DHCPv4 server: dhcpd.
Jun 30 09:57:30 DietPi systemd[1]: Started isc-dhcp-server.service - LSB: DHCP server.
14

pls reboot your system and check logs again.

15

did that and now the network itself works.
thank you so much for the help

16

ok good, keep an eye on your SD card as it might cause issues in future again.