{"id":3543,"date":"2019-11-04T10:00:58","date_gmt":"2019-11-04T16:00:58","guid":{"rendered":"https:\/\/www.foell.org\/justin\/?p=3543"},"modified":"2021-01-03T13:32:28","modified_gmt":"2021-01-03T19:32:28","slug":"chaining-dnsmasq-and-resolved","status":"publish","type":"post","link":"https:\/\/www.foell.org\/justin\/chaining-dnsmasq-and-resolved\/","title":{"rendered":"Chaining DNSMasq and resolved"},"content":{"rendered":"

I had a weird problem recently that I solved, and it was mostly due to my mis-configuring of my Ubuntu laptop. I finally figured it out when setting up my new Dell XPS Developer Edition laptop<\/a>, so I wanted to share.<\/p>\n

The situation: I would go to my local library and couldn’t connect to their wireless internet. But if I disabled dnsmasq and restarted the network-manager service, it would work fine.<\/p>\n

What I didn’t realize was happening is dnsmasq was taking over local DNS control from the systemd-resolved service. What is systemd-resolved and why is it important? The man page reads:<\/p>\n

systemd-resolved<\/strong><\/span>\u00a0is a system service that provides network name resolution to local applications. It implements a caching and validating DNS\/DNSSEC stub resolver, as well as an LLMNR and MulticastDNS resolver and responder.<\/p><\/blockquote>\n

My library uses a captive portal<\/a>. When you connect to their network it brings up a page that makes you agree before actually being able to use the network. systemd-resolved has all the know-how to handle that – dnsmasq doesn’t.<\/p>\n

I love dnsmasq<\/a> and don’t want to lose it’s functionality. I want to use both the system resolved (pronounced resolve-D) and<\/em> dnsmasq. Here’s how to have your cake and eat it too.<\/p>\n

<\/p>\n

DNSMasq via NetworkManager<\/h2>\n

To use the dnsmasq plugin that is installed with NetworkManager, I just needed to add the bold<\/strong> line to the main section of NetworkManager.conf<\/code> via sudo vi \/etc\/NetworkManager\/NetworkManager.conf<\/code><\/p>\n

[main]\nplugins=ifupdown,keyfile\ndns=dnsmasq<\/strong>\n<\/pre>\n
Local sites<\/h2>\n
This section is optional, I do it to create a local domain name that only exists on my local computer for web development purposes. Anything that ends in .test<\/code> resolves to localhost. Also, I use a loopback IP address for my .test addresses<\/a> in case I need to access them through a virtual machine (usually to test IE).<\/p>\n
Then add this file, by running sudo vi \/etc\/NetworkManager\/dnsmasq.d\/01-dot-test.conf<\/code><\/p>\n
address=\/test\/10.254.254.254\n<\/pre>\n
Why do I use .test? See this post.<\/a><\/p>\n
Chaining DNSMasq & resolveconf<\/h2>\n
To really make things work I wanted to keep both resolved and dnsmasq working together in tandem<\/em>. I found the answer in this thread on ubuntuforums.org<\/a>. resolved just needs to know to use dnsmasq as its upstream provider. You can do this by adding the following bold<\/strong> lines via sudo vi \/etc\/systemd\/resolved.conf<\/code><\/p>\n
[Resolve]\nDNS=127.0.1.1<\/strong>\nFallbackDNS=127.0.1.1\nDomains=lan local test<\/strong><\/pre>\n
The Domains<\/code> line is present in Ubuntu 18.04 as lan local<\/code> and it works like that. In 20.04 it is not present, but needs to be there with your dnsmasq domain(s) (test<\/code> in my case) in order to pass queries for that domain to dnsmasq upstream – otherwise resolved ignores them.<\/p>\n
You can restart network-manager and systemd-resolved services to apply your changes, or simply reboot your system.<\/p>\n
Test it out<\/h2>\n
To make sure that it’s working, first check your resolv.conf file by running cat \/etc\/resolv.conf<\/code><\/p>\n
# This file is managed by man:systemd-resolved(8). Do not edit.\n...\n# Run \"systemd-resolve --status\" to see details about the uplink DNS servers\n# currently in use.\n...\n\nnameserver 127.0.0.53\n...\n<\/pre>\n
This file should be managed by resolved and use the resolved IP of 127.0.0.53. Then use the hint given in that file to check the upstream server: systemd-resolve --status<\/code><\/p>\n
Global\n         DNS Servers: 127.0.1.1\n          DNSSEC NTA: 10.in-addr.arpa\n                      ...\n                      corp\n                      d.f.ip6.arpa\n                      home\n                      internal\n                      intranet\n                      lan\n                      local\n                      private\n                      test\n<\/pre>\n
Ping a couple of domain names, both local and remote, and you should be good to go!<\/p>\n
Send to Kindle<\/span><\/div>","protected":false},"excerpt":{"rendered":"
I had a weird problem recently that I solved, and it was mostly due to my mis-configuring of my Ubuntu laptop. I finally figured it out when setting up my new Dell XPS Developer Edition laptop, so I wanted to share. The situation: I would go to my local library and couldn’t connect to their… Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"Chaining DNSMasq and systemd-resolved in Ubuntu for the best of all DNS worlds","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[1,8],"tags":[164,23,168],"class_list":["post-3543","post","type-post","status-publish","format-standard","hentry","category-business","category-ubuntu","tag-dell","tag-dnsmasq","tag-xps13"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t