Switch to systemd-resolved

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No problem to start using systemd-resolved for DNS; it is already installed by default since systemd provides it. It’s a small matter setting up a config file and enabling the service.

Read through the man page for resolved.conf to decide what options you want to set, then edit /etc/systemd/resolved.conf (or set up some drop-in configs in /etc/systemd/resolved.conf.d/…or both!).

Enable the service:

sudo systemctl enable --now systemd-resolved.service

Unless you want to use something other than the stub mode, set up a symlink to /etc/resolv.conf, which is the file that a lot of software that calls for DNS resolution (web browsers, for example) will use. See this note from the ArchWiki article:

DNS

Software that relies on glibc’s getaddrinfo(3) (or similar) will work out of the box, since, by default, /etc/nsswitch.conf is configured to use nss-resolve(8) if it is available.

To provide domain name resolution for software that reads /etc/resolv.conf directly, such as web browsers and GnuPG, systemd-resolved has four different modes for handling the file—stub, static, uplink and foreign. They are described in systemd-resolved(8) § /ETC/RESOLV.CONF. We will focus here only on the recommended mode, i.e. the stub mode which uses /run/systemd/resolve/stub-resolv.conf.

/run/systemd/resolve/stub-resolv.conf contains the local stub 127.0.0.53 as the only DNS server and a list of search domains. This is the recommended mode of operation that propagates the systemd-resolved managed configuration to all clients. To use it, replace /etc/resolv.conf with a symbolic link to it:

# ln -rsf /run/systemd/resolve/stub-resolv.conf /etc/resolv.conf

Note:

  • Failure to properly configure /etc/resolv.conf will result in broken DNS resolution.
  • Creating the /etc/resolv.conf symlink will not be possible while inside arch-chroot, since the file is bind-mounted from the outside system. Instead, create the symlink from outside the chroot. E.g.
# ln -sf /run/systemd/resolve/stub-resolv.conf */mnt*/etc/resolv.conf

A symlink to /etc/resolv.conf is the only configuration I have seen used on systems that use systemd-resolved. My understanding is it’s a method that simplifies the configuration in a significant way.

That’s pretty much it to get up and going. Read through the rest of the ArchWiki article if you want to dive a little deeper on setting up DNS servers (sounds like you might want to :wink:), or if you need to disable mDNS (it is enabled by default on systemd-resolved) or anything else like that.

I hope that helps, welcome to the community @carroarmato0. :slightly_smiling_face:

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