DHCP server won't assign ip after migration

[francio87]

After migrating from version 7.9 to version 8, if there were no DHCP servers enabled in version 7, the DHCP server in version 8 does not assign IP addresses even if enabled.

Steps to reproduce

• Install a NS7, make sure to not enable DHCP server
• Migrate the configuration on a 8
• Enable DHCP Server on 8

Expected behavior

DHCP server give out IP address to clients

Actual behavior

The server recive the DHCP and after an initial offer it reply with a NAK and the message no leases left

Jun 11 17:44:24 xxxx dnsmasq-dhcp[1]: DHCPDISCOVER(eth0) 98:xx:xx:xx:xx:x
Jun 11 17:44:24 xxxx dnsmasq-dhcp[1]: DHCPOFFER(eth0) 192.168.1.212 98:xx:xx:xx:xx:x
...
...
Jun 11 17:44:30 xxxx dnsmasq-dhcp[1]: DHCPNAK(eth0) 192.168.1.212 98:xx:xx:xx:xx:xx no leases left
Jun 11 17:44:30 xxxx dnsmasq-dhcp[1]: DHCPNAK(eth0) 192.168.1.212 98:xx:xx:xx:xx:xx no leases left

Looking at the uci configuration this option get set under the dhcp configuration :

option dhcpleasemax '0'

The export.tar.gz file, has inside the dhcp.json file :

{"general":{"dhcpleasemax":0,"rebind_protection":"0"},"reservations":[],"servers":[]}

Removing the option dhcpleasemax solve the issue:

root@test-ns8:~# diff -u /tmp/dhcp /etc/config/dhcp
--- /tmp/dhcp   2024-06-12 12:25:26.000000000 +0200
+++ /etc/config/dhcp    2024-06-12 15:54:12.432474929 +0200
@@ -20,7 +20,6 @@
        option ednspacket_max '1232'
        option filter_aaaa '0'
        option filter_a '0'
-       option dhcpleasemax '0'
        option enable_tftp '1'
        option allservers '1'
        option logqueries '0'

[filippocarletti]

I think we can ignore the size of the DHCP pool. Or handle the value 0 as a special case. A default clean installation of version 8 doesn't set dhcpleasemax.

[gsanchietti]

Testing image: 23.05.3-ns.1.0.1-12-g33ff78b

[francio87]

Confirm, fixed. Tested with the same export file, the value dhcpleasemax it's not present anymore :

root@ns79-mig:~# uci show dhcp |grep dhcpleasemax
root@ns79-mig:~#