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I've configured a dnsmasq service into my servers network. I can query it correctly from local server and "brothers" servers in the network.

root@yyy ~# nslookup google.com 172.25.x.xxx
Server:     172.25.x.xxx
Address:    172.25.x.xxx#53

Non-authoritative answer:
Name:   google.com
Address: 216.58.210.174

However when I try to query it from my dev machine (range 172.144.x.x) I get no response. Ports are correctly open (tested with nmap and telnet).

$ nmap -p 53 172.25.x.xxx -Pn

Starting Nmap 7.01 ( https://nmap.org ) at 2017-04-12 17:54 CEST
Nmap scan report for 172.25.x.xxx
Host is up (0.0018s latency).
PORT   STATE SERVICE
53/tcp open  domain

Nmap done: 1 IP address (1 host up) scanned in 0.05 seconds

$ nslookup google.com 172.25.x.xxx
connection timed out; no servers could be reached

It seems like the flag --local-service is enabled however I've set interface and listen-address variables

interface=eth0
listen-address=127.0.0.1,172.25.x.xxx

I've saw that --local-service is enabled by default but not when using "interface" and "listen-address". Is there any way to check in is still active?

edit Seems it could be a udp/tcp related issue. This query works from my dev network

$ dig +tcp +short cnn.com @172.25.7.110
151.101.129.67
151.101.193.67

It seems strange because dev and server machines can "talk" udp. (tested with "netcat -u -l -p 53" on server and "netcat -u 172.25.x.xxx 53" on dev machine)

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The firewall rules is the culprit it seems. Check the nmap list: 53/tcp. Make sure UDP is allowed as well.

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