dnsmasq dhcp – DHCP Within DNSMASQ Not Reached for IP Address Requests

dhcpdhcp-serverdnsmasq

Due to a device loss in the network, a new DNSMASQ configuration has been brought in on a different server. The server happens to be a Raspberry Pi 4B. Many devices are able to obtain IP addresses, but some (Windows 10 devices in particular) are timing out on the DHCP request. This is new; there was no known problem before with DHCP, and I don't any reason for this configuration to be biased. The configuration is:

# Use interface wlan0
#interface=eth0
#interface=lo
#interface=wlan0

listen-address=10.158.54.3
listen-address=127.0.0.1

bind-interfaces

# Don't forward unqualified names (hpmicro1)...
domain-needed

# Don't forward some non-routed addresses
bogus-priv

# don't forward requests for the intranet subdomain
local=/lovelady.com/

# Assign addresses between 10.158.54.65 and 10.158.54.200 with a 24 hour lease time
dhcp-range=10.158.54.101,10.158.54.200,12h

# Forward DNS requests to the local DNS and then Google DNS
server=10.158.54.3
server=8.8.8.8
server=8.8.4.4

dhcp-option=option:router,10.158.54.1    # Default gateway
dhcp-option=6,10.158.54.3               # DNS (that's me)

# append domain to all hosts
domain=lovelady.com

expand-hosts # Add domain also to any simple names in /etc/hosts    

dhcp-host=b4:2e:99:a2:58:77,Velmicro
dhcp-host=ac:1f:6b:17:f6:25,NAS-1,10.158.54.10
dhcp-host=ac:1f:6b:9a:cb:6c,PLEX-NAS1
dhcp-host=b8:27:eb:ba:a0:7b,pi-in-the-sky
dhcp-host=00:1c:d2:f1:94:3d,inet-radio
dhcp-host=38:f7:3d:b1:12:3f,Amazon-BSMT
dhcp-host=fc:a1:83:43:30:76,Amazon-LivRm
dhcp-host=20:df:b9:57:9d:46,Google-Home
dhcp-host=b8:27:eb:9b:e1:91,octopi-w,10.158.54.20
dhcp-host=50:87:b8:00:8e:46,luvtablo

Would appreciate any help you can provide…

Best Answer

Turns out that the message about timeout is misleading. Apparently since recent versions of Windows 10, the system will sometimes try to reset the loopback interface (a.k.a. localhost, or 127.0.0.1) and that is what the error was saying. After windoze finally timed out on the loopback interface, it obtained an IP address for the other applicable interfaces. Windows should not ever try to reset the localhost interface, and usually it doesn't. But it has moods, apparently.