Gentoo Archives: gentoo-user

From: Rich Freeman <rich0@g.o>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] systemd DNS does not resolve 'local' addresses
Date: Sat, 02 Apr 2022 21:48:28
Message-Id: CAGfcS_mJti6hwDhsm5o2LCyRaF15HGFe1JuhBwtf3Hg=JeMoQg@mail.gmail.com
In Reply to: [gentoo-user] systemd DNS does not resolve 'local' addresses by Alexander Puchmayr
1 On Sat, Apr 2, 2022 at 5:22 PM Alexander Puchmayr
2 <alexander.puchmayr@×××××××.at> wrote:
3 >
4 > ## portage.local maps to 192.168.1.6
5 > ## DNS-Server provided via DHCP is 192.168.1.1 (openwrt-router)
6 >
7 > buildhost-desktop ~ # ping portage.local
8 > ping: portage.local: Temporary failure in name resolution
9 >
10 > Protocols: +LLMNR +mDNS -DNSOverTLS DNSSEC=no/unsupported
11
12 So, I haven't really used resolved much, but I see you have mDNS
13 enabled. Does the portage.local host broadcast itself using mDNS? If
14 it is running Gentoo then the answer is no unless you have it running
15 avahi, which is usually not installed by default. Many
16 desktop-oriented linux distros provide avahi by default.
17
18 A resolver that supports mDNS will not use DNS to resolve the .local
19 TLD, in accordance with RFC 6762.
20
21 If you intend to use .local for DNS and not mDNS then you probably do
22 not want mDNS enabled. You can either disable it for resolved
23 globally by setting MulticastDNS=no in the [Resolve] section of
24 /etc/systemd/resolved.conf, or by disabling it for a specific network
25 in your network manager (the setting has the same name for
26 systemd-networkd).
27
28 This is one of those reasons why it is best to not use the .local TLD
29 for DNS on your home network. You can disable it on systemd-resolved,
30 but some IoT device in your home might have it permanently enabled.
31 It allows a form of name resolution to work without any DNS server as
32 devices discover and broadcast on their own.
33
34 --
35 Rich

Replies

Subject Author
Re: [gentoo-user] systemd DNS does not resolve 'local' addresses Alexander Puchmayr <alexander.puchmayr@×××××××.at>