Can't resolve a host when listen_adresses is empty

[lamualfa]

Original issue #2935

Description

dnscrypt-proxy -resolve must have the same listen_addresses value or value resolving mechanism with dnscrypt-proxy command ran by systemctl to make it consistent & seamless.

Configuration

sudo cat /etc/dnscrypt-proxy/dnscrypt-proxy.toml

# Empty listen_addresses to use systemd socket activation
listen_addresses = []
server_names = ['cloudflare']

[query_log]
  file = '/var/log/dnscrypt-proxy/query.log'

[nx_log]
  file = '/var/log/dnscrypt-proxy/nx.log'

[sources]
  [sources.'public-resolvers']
  url = 'https://download.dnscrypt.info/resolvers-list/v2/public-resolvers.md'
  cache_file = '/var/cache/dnscrypt-proxy/public-resolvers.md'
  minisign_key = 'REDACTED'
  refresh_delay = 72
  prefix = ''

Test resolving a host

dnscrypt-proxy -resolve reddit.com

Resolving [reddit.com] using 127.0.0.1 port 53

Unable to resolve: [read udp 127.0.0.1:44316->127.0.0.1:53: read: connection refused]

Service status

sudo systemctl status dnscrypt-proxy

● dnscrypt-proxy.service - DNSCrypt client proxy
     Loaded: loaded (/usr/lib/systemd/system/dnscrypt-proxy.service; enabled; preset: enabled)
     Active: active (running) since Wed 2025-08-20 18:09:46 REDACTED; 1min 21s ago
TriggeredBy: ● dnscrypt-proxy.socket
       Docs: https://github.com/DNSCrypt/dnscrypt-proxy/wiki
   Main PID: 42919 (dnscrypt-proxy)
      Tasks: 13 (limit: 18625)
     Memory: 7.1M (peak: 7.8M)
        CPU: 169ms
     CGroup: /system.slice/dnscrypt-proxy.service
             └─42919 /usr/sbin/dnscrypt-proxy -config /etc/dnscrypt-proxy/dnscrypt-proxy.toml

Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] dnscrypt-proxy 2.0.45
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] Network connectivity detected
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [WARNING] Systemd sockets are untested and unsupported - use at your own risk
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] Wiring systemd TCP socket #0, dnscrypt-proxy.socket, 127.0.2.1:53
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] Wiring systemd UDP socket #1, dnscrypt-proxy.socket, 127.0.2.1:53
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] Source [public-resolvers] loaded
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] Firefox workaround initialized
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] [cloudflare] OK (DoH) - rtt: 8ms
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] Server with the lowest initial latency: cloudflare (rtt: 8ms)
Aug 20 18:09:46 my-computer dnscrypt-proxy[42919]: [2025-08-20 18:09:46] [NOTICE] dnscrypt-proxy is ready - live servers: 1

Netstat

sudo netstat -tpln|grep ":53"

tcp        0      0 127.0.2.1:53            0.0.0.0:*               LISTEN      1/init
tcp        0      0 127.0.0.54:53           0.0.0.0:*               LISTEN      39894/systemd-resol
tcp        0      0 127.0.0.53:53           0.0.0.0:*               LISTEN      39894/systemd-resol

[lifenjoiner]

Found this: https://github.com/DNSCrypt/dnscrypt-proxy/wiki/Installation-linux#systemd-sockets-activation

[lifenjoiner]

I'm not a Linux user.
Happened to just read the code about systemd socket, and I'm curious to know:
Does it work, if listen_addresses is set with the listen address of you dnscrypt-proxy.socket?

dnscrypt-proxy/dnscrypt-proxy/example-dnscrypt-proxy.toml

Line 40 in e32fd47

listen_addresses = ['127.0.0.1:53']

Ref: https://github.com/DNSCrypt/dnscrypt-proxy/wiki/systemd#update-for-v2045

BTW, v2.0.45 is really old, and missing many important improvements.