Set custom DNS resolver curl
Override DNS for a host:port pair (test behind CDN/LB)
curl --resolve example.com:443:1.2.3.4 https://example.com
more curl
all 21 commands →
Retry on failure
curl --retry 5 --retry-delay 2 --retry-all-errors https://api.example.com/healthz
POST form data
curl -d 'user=alice&pass=secret' -X POST https://auth.example.com/login
Client certificate auth
curl --cert client.crt --key client.key --cacert ca.crt https://secure.example.com
Parallel downloads with xargs
cat urls.txt | xargs -P 5 -I{} curl -sSL -o /dev/null -w '%{url_effective} %{http_code}\n' {}
WebSocket handshake test
curl -i -N -H 'Upgrade: websocket' -H 'Connection: Upgrade' -H 'Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==' -H 'Sec-WebSocket-Version: 13' http://localhost:8080/ws