cURL: Selecting a custom DNS server to resolve domain names

curl_custom_dns.sh

#!/usr/bin/env bash

# this can be useful when developing against a custom DNS server, or 
# for example, if you made a change to the DNS settings of a domain, and you 
# know the authoritative nameserver IP address for a domain, you could use this 
# to bypass the intermediate DNS cache, and apply an HTTP request using the new 
# DNS settings supplied by your specified (authoritative) nameserver

curl --dns-servers <DNSIP,DNSIP> url.com

# acquire the authoritative nameserver IP using

dig url.com NS

# then ping the NS to get its IP address

# you can also directly resolve

curl \
  --resolve www.example.com:443:198.14.3.5 \
  https://www.example.com \
  --verbose

@hisashiyamaguchi

I have the same issue - any ideas would be appreciated.

brew install curl-openssl

still no joy

$ brew install curl-openssl 

$ /opt/homebrew/opt/curl/bin/curl --version                                                                                                                       
curl 8.11.1 (aarch64-apple-darwin24.1.0) libcurl/8.11.1 OpenSSL/3.4.0 (SecureTransport) zlib/1.2.12 brotli/1.1.0 zstd/1.5.6 AppleIDN libssh2/1.11.1 nghttp2/1.64.0 librtmp/2.3
Release-Date: 2024-12-11
Protocols: dict file ftp ftps gopher gophers http https imap imaps ipfs ipns ldap ldaps mqtt pop3 pop3s rtmp rtsp scp sftp smb smbs smtp smtps telnet tftp ws wss
Features: alt-svc AsynchDNS brotli GSS-API HSTS HTTP2 HTTPS-proxy IDN IPv6 Kerberos Largefile libz MultiSSL NTLM SPNEGO SSL threadsafe TLS-SRP UnixSockets zstd

$ /opt/homebrew/opt/curl/bin/curl --dns-servers 8.8.8.8   
curl: option --dns-servers: the installed libcurl version does not support this

maybe curl-openssl is not using it's own libcurl lib it installed to /opt/homebrew/opt/curl/lib?

Curl compiled with C-ares is here.

$ ver && echo; && curl --version
Microsoft Windows [Version 6.1.7601]

curl 8.13.0 (x86_64-w64-mingw32) libcurl/8.13.0 OpenSSL/3.4.1 brotli/1.1.0 zstd/1.5.7 c-ares/1.34.4 libidn2/2.3.8 libpsl/0.21.5 libssh2/1.11.1 nghttp2/1.65.0 nghttp3/1.8.0
Release-Date: 2025-04-02
Protocols: dict file ftp ftps gopher gophers http https imap imaps ipfs ipns mqtt pop3 pop3s rtsp scp sftp smb smbs smtp smtps telnet tftp ws wss
Features: alt-svc AsynchDNS brotli HSTS HTTP2 HTTP3 HTTPS-proxy IDN IPv6 Largefile NTLM PSL SSL SSLS-EXPORT threadsafe TLS-SRP TrackMemory UnixSockets zstd