How to Build a Bind9 Docker Image

[@Glatze603]

Hi Dave and thanks for the video and the content 🙂I am playing around with dns (and in combination with dhcp) in my homelab and I am still looking for a complete solution: I have a dhcp serverand I want a computer to get an ip address from this dhcp server (not reserved), I want that the ip, the computer name and the domain name are registered in the dns server, so that the computer can be resolved with it´s ip address and with it´s computer name and with it´s fqdn, too. The dns server should be an authoritative dns server, too. I found an open source application "technitium dns server" that seems to be a feature rich and secure solution. Maybe you could make a video about it?

[@TechTutorialsDavidMcKone]

I'm using Kea to do DDNS with Bind They're by the same company and work well together

[@AdrianuX1985]

+1

[@pursue_eternity]

secure (thanks for using "bind" user) and easy to follow vid. Everything worked as expected however that "rndc reload" isn't really updating my zone file (i also update the serial number). I still get old entry when looking up. "docker restart " this works but what's up with "rndc reload"?

[@TechTutorialsDavidMcKone]

That's strange I've just created a new A record and rndc reload is working fine But are you editing an existing entry? If so it's possible you're running into a caching problem The client computer will cache a DNS lookup, so even if you update the DNS server, the client will use what's in it's own cache until it times out after maybe 24 hours Likewise, the DNS server will cache DNS lookups until the TTL expires, but a container restart probably wipes that out, forcing it to read from the database file again

[@pursue_eternity]

rndc reload shows the same output server reload successful. But when viewing in the /etc/bind/db., it doesn't show new A record so obviously when exiting from the container and using host command shows "Host not found: 3(NXDOMAIN)

[@TechTutorialsDavidMcKone]

@@pursue_eternity That's odd because the file on the host should be the same one that the container uses So when you update the file on the host, the container should be updated What the rndc reload command does is to get bind9 to read the config file into memory again What OS are you running Docker on? I've got a VM running Debian 12.6 and that works

[@pursue_eternity]

@@TechTutorialsDavidMcKone tried on ubuntu server 22.04 and arch linux 2024.08.01, same issue.

[@TechTutorialsDavidMcKone]

@@pursue_eternity Very odd that. It sounds like quite a rabbit hole. I was just reading about files not being updated due to a bug in Docker, but that thread is quite old. Also there can be situations where if you mount a single file it may not get synched so a directory mount can be better. Fortunately, a container restart resolves these

[@michaelcooper5490]

Another great video David, Thank you for your work.

[@TechTutorialsDavidMcKone]

Thanks for taking the time to comment and good to know the video was useful

[@agatamarozas9860]

Matrix and Hollywood in background love it :)

[@TechTutorialsDavidMcKone]

Yes, it's certainly an interesting background choice :)

[@BillyDickson]

Thanks Dave, much appreciated. Might have a bash at creating an Unbound recursive DNS resolved at summer point and see where it lands me. 👍

[@TechTutorialsDavidMcKone]

Well if you want more of a challenge try adding DNS over HTTP (DoH) Seems to be getting more preference over DNS over TLS (DoT) These Firefox browsers are being fussy

[@iomarian13]

thanks a lot for your video keep doing these kind of videos.

[@TechTutorialsDavidMcKone]

Glad you liked the video And there are a lot more in the pipeline

[@IleniaQuintero]

Hello, I was looking at your video channel. We may be helping a company that uses secure images to increase supply chain security and help cloud native development. Would you be willing to help try their software, make a video, and help show devs how to use their tools? This is not an offer, but just to start a conversation about your willingness to take on sponsorship. Please provide me with your email if you are interested. You'd have a chance to look at their technology and decide if it's the type of software that you'd be interested in covering in your channel.

[@TechTutorialsDavidMcKone]

Thanks for asking I don't do software development but if you can provide a link to the website I might still look into this to see if anything fits in with what I cover on this channel