[Dnsmasq-discuss] no address available with static range and dhcp-host

[Nicolas Granger]

Le 15/01/2025 à 18:12, Geert Stappers a écrit :
> On Wed, Jan 15, 2025 at 04:28:53PM +0100, Nicolas Granger wrote:
>> Le 15/01/2025 à 13:54, john doe via Dnsmasq-discuss a écrit :
>>> On 1/15/25 11:50, GRANGER Nicolas wrote:
>>>> Hi all,
>>>>
>>>>
>>>> I am unable to get dnsmasq to issue ip addresses to known hosts
>>>> only. Upon DHCPDISCOVER it fails with no address available.
>>>>
>>>>
>>>> The network interface is called lan with ip address 192.168.2.254/24
>>>>
>>>>
>>>> $ sudo dnsmasq -d --bind-interfaces -i lan --except-interface=lo \
>    --dhcp-range=192.168.2.0,static,255.255.255.0 \
>    --dhcp-host=ac:1f:xx:xx:xx:xx,192.168.2.19
>>>>
>>> for a simple /24, I don't specify a netmask!
>>>
>>> Are you sure that the client is sending the mac address that you are
>>> expecting?
>>>
>>> What version of Dnsmasq are you using?
>>>
>> The version is 2.90 and the mac address is correct.
>>
>> With a regular dhcp-range, dnsmasq pulls an ip from the range, not the one
>> of the host.
>>
>> $ sudo dnsmasq -d --bind-interfaces -i lan --except-interface=lo \
>    --dhcp-range=192.168.2.100,192.168.2.150,255.255.255.0 \
>    --dhcp-host=ac:1f:xx:xx:xx:xx,192.168.2.19
>> dnsmasq: started, version 2.90 cachesize 150
>> dnsmasq: compile time options: IPv6 GNU-getopt DBus no-UBus i18n IDN2 DHCP
>> DHCPv6 no-Lua TFTP conntrack ipset nftset auth cryptohash DNSSEC loop-detect
>> inotify dumpfile
>> dnsmasq-dhcp: DHCP, static leases only on 192.168.2.0, lease time 1h
>> dnsmasq-dhcp: DHCP, IP range 192.168.2.100 -- 192.168.2.150, lease time 1h
>> dnsmasq-dhcp: DHCP, sockets bound exclusively to interface lan
>> dnsmasq: reading /etc/resolv.conf
>> dnsmasq: using nameserver 127.0.0.53#53
>> dnsmasq: read /etc/hosts - 8 names
>> dnsmasq-dhcp: DHCPDISCOVER(lan) 192.168.2.56 ac:1f:xx:xx:xx:xx
>> dnsmasq-dhcp: DHCPOFFER(lan) 192.168.2.101 ac:1f:xx:xx:xx:xx
>> dnsmasq-dhcp: DHCPREQUEST(lan) 192.168.2.101 ac:1f:xx:xx:xx:xx
>> dnsmasq-dhcp: DHCPACK(lan) 192.168.2.101 ac:1f:xx:xx:xx:xx node19
>>
> And what can be seen on the wire?
>
>
>
> Groeten
> Geert Stappers

The long lease time by default misled me to think the renewal
failed. It eventually switches to the desired address at the end of the
lease:

DHCPREQUEST(lan) 192.168.2.19ac:1f:xx:xx:xx:xx
DHCPNAK(lan) 192.168.2.19ac:1f:xx:xx:xx:xx address not available
DHCPREQUEST(lan) 192.168.2.19ac:1f:xx:xx:xx:xx
DHCPNAK(lan) 192.168.2.19ac:1f:xx:xx:xx:xx address not available
DHCPDISCOVER(lan) 192.168.2.19ac:1f:xx:xx:xx:xx
DHCPOFFER(lan) 192.168.2.1ac:1f:xx:xx:xx:xx
DHCPREQUEST(lan) 192.168.2.1ac:1f:xx:xx:xx:xx
DHCPACK(lan) 192.168.2.1ac:1f:xx:xx:xx:xx node19

Thanks for the help.