dnsmasq

Ubuntu Pi-hole DNS Fix: Pi-hole could not start DNS service after upgrading Ubuntu

 in GNU/Linux  tagged daemon / DNS / dnsmasq / Faster Than Light / FTL / LTS / LXD / pi-hole / pihole / server / service / ubuntu by

Ubuntu is a widespread Linux distribution that has gained popularity over the years. One of the advantages of Ubuntu is its Long-Term Support (LTS) releases, which have been supported for several years and receive regular updates and security patches. Upgrading from one LTS release to another is a common task for Ubuntu users. However, sometimes things don’t go as planned, and some services may fail to start after the upgrade. In this blog post, we will explore one issue that Ubuntu users may encounter when upgrading from 18.04LTS to 20.04LTS or 22.04LTS and how to fix it.

The problem we will discuss is related to Pi-hole, a popular network-level advertisement and Internet tracker blocking application. Pi-hole uses DNS (Domain Name System) to stop unwanted traffic on your network. After upgrading from Ubuntu 18.04LTS to 20.04LTS or 22.04LTS, some users may encounter an issue where the DNS service for Pi-hole fails to start. The reason behind this is a broken symbolic link at /etc/dnsmasq.d/lxd.

LXD is a system container manager that allows users to run multiple isolated Linux systems (containers) on a single host. During the upgrade process, the symbolic link for LXD may become broken, causing the DNS service for Pi-hole to fail to start. Fortunately, the solution to this problem is simple. Users can remove the broken symbolic link by running the following command in the terminal:

sudo rm /etc/dnsmasq.d/lxd;

Once the broken symbolic link is removed, users can restart the DNS service for Pi-hole by running the following command:

pihole restartdns;

This command will restart the Pi-hole FTL (Faster Than Light) daemon, which handles DNS requests and blocks unwanted traffic.

In conclusion, upgrading from one LTS release to another is a common task for Ubuntu users. However, sometimes things may not go as planned, and some services may fail to start after the upgrade. One such issue that users may encounter is related to Pi-hole, where the DNS service fails to start due to a broken symbolic link at /etc/dnsmasq.d/lxd. Fortunately, the solution to this problem is simple, and users can fix it by removing the broken symbolic link and restarting the Pi-hole FTL daemon.

How to Create a Custom Local DNS Entry on a Ubiquity Dream Machine Pro

 in GNU/Linux  tagged DNS / DNS Entry / dnsmasq / Dream Machine Pro / HostKeyAlgorithms / Local DNS Entry / PubkeyAcceptedKeyTypes / ssh / ssh-rsa / Ubiquity by

DNS (Domain Name System) is an essential part of the internet infrastructure that translates domain names into IP addresses. However, you can also use DNS for internal networks to assign custom hostnames to specific IP addresses. In this post, we will discuss how to create a custom local DNS entry on a Ubiquity Dream Machine Pro.

The first step is to assign a static IP address to the machine you want to create a custom DNS entry for. To do this, log in to the Dream Machine Pro’s web interface and navigate to https://10.1.1.254/network/default/clients. Find the machine you want to assign a static IP address to and click the “Static” button. Enter the IP address you want to assign and click “Save”.

Next, you need to assign a specific hostname to the machine. However, you might run into an error message that says “An error occurred while changing your settings”. This error occurs when you use a specific domain name like “bytefreaks.lcl”. To work around this issue, you can use a different TLD like “.net” instead.

If you still want to use the “.lcl” TLD, you will need to SSH into the Dream Machine Pro to modify the configuration files. Use the following SSH command to log in as root:

ssh -p 22 -o HostKeyAlgorithms=+ssh-rsa -o PubkeyAcceptedKeyTypes=+ssh-rsa [email protected];

If the default SSH command produces an error, you can use the above custom SSH command to log in successfully.

Once you have logged in via SSH, you will need to modify the following files:

  • /run/dnsmasq.conf.d/dns.conf
  • /mnt/data/udapi-config/ubios-udapi-server/ubios-udapi-server.state

The /run/dnsmasq.conf.d/dns.conf and /mnt/data/udapi-config/ubios-udapi-server/ubios-udapi-server.state files contain information about the local DNS entries. Use the “vi” editor to modify the /run/dnsmasq.conf.d/dns.conf file and replace the “.net” TLD with the “.lcl” TLD.

After you have made the necessary changes, exit the editor and kill the dnsmasq process using the following command:

pkill dnsmasq;

This command will stop the dnsmasq process, which is responsible for the DNS resolution. Then, execute dnsmasq again to ensure that it is running properly.

Now, you should be able to view your machine using the custom “.lcl” TLD from a browser. By creating a custom local DNS entry, you can simplify your local network administration and access your devices more easily.