What we ran
On September 14, 2026, we ran a Node.js HTTPS server bound only to 127.0.0.1 and tested it with curl 8.7.1 on macOS using Node v24.19.0. The server returned the synthetic marker new-host-synthetic-marker. A one-day test certificate covered preflight.test and www.preflight.test; its private key existed only in memory.
The client trusted that test certificate explicitly. We did not disable certificate checks, alter system DNS or the system trust store, use a vendor account, or connect to a production site. These observations cannot establish Kinsta, WP Engine, or Liquid Web performance.
Four observed results
| Case | Observed result | What it establishes |
|---|---|---|
| --resolve to loopback | HTTP 200 and the expected marker; Host and SNI remained preflight.test | The URL hostname survives the destination override |
| wrong.test against the same certificate | curl exit 60; no HTTP request reached the handler | The destination override did not bypass hostname verification |
| 302 redirect without --location | HTTP 302; destination not fetched | A redirect response is not a successful destination check |
| Follow redirect with a second explicit mapping | HTTP 200 and marker; SNI became www.preflight.test | The second hostname needs its own test route and valid certificate |
Reproduce the result
Download the runnable source below and run node host-preflight-demo.mjs from a local working directory. It requires Node.js, curl, and OpenSSL with -addext support, plus /dev/stdin as on macOS or Linux. No npm packages are required. It creates an ephemeral loopback listener and prints a timestamped JSON report; failed assertions produce a nonzero exit.
The source contains the complete curl argument lists. The local port changes on each run; the report replaces it with LOCAL_PORT. The certificate and private key are not saved. Do not substitute a production hostname or customer data into this demonstration.
Apply the result without overstating it
For an actual pre-DNS migration check, verify a destination-specific marker as well as the status code. Review each redirect hostname before following it. A 200 response from the wrong host can look healthy while testing the wrong environment.
This fixture has no WordPress database, login system, payment integration, cache layer, or real DNS cutover. Test those separately before declaring a migration ready. Our course and hosting comparisons remain documentation research; this local result is not a vendor benchmark.
Sources & verification
Product details and prices can change. Check the linked provider before buying.
- curl project: hostname resolution overrides and HTTPS Accessed 2026-09-14
Sources link directly to providers. Product buttons may use separately labeled affiliate links. Read our disclosure.