Cloudflare Redirect Loops: Fixing HTTP↔HTTPS and Host Canonicalization with CloudBypass API

Redirect loops are one of the most disruptive Cloudflare-side failures because they can look like “the site is down,” while every component is technically working. The browser receives responses, the origin is reachable, and Cloudflare is issuing legitimate redirects—yet the client never lands on a stable final URL. In production pipelines, this becomes even harder to diagnose, because different workers can follow redirects differently, carry cookies inconsistently, or hit different edge paths that enforce different canonicalization outcomes.

This article explains the two most common redirect loop families—HTTP↔HTTPS loops and hostname canonicalization loops—and provides a practical fix workflow. It also highlights how CloudBypass API (穿云API) helps teams keep routing, session state, and redirect handling consistent across distributed execution, so loops do not reappear as “random” incidents.

1. What a Redirect Loop Really Is

A redirect loop is not “too many redirects” as a generic error. It is a contradictory policy chain. Somewhere, two or more layers disagree about what the canonical URL should be, or they apply rules in an order that sends the client back and forth.

Most loops are created by combinations of:

  • Cloudflare settings (Always Use HTTPS, Automatic HTTPS Rewrites, forwarding rules, transform rules).
  • Origin redirects (web server config, app middleware, framework canonicalization).
  • Proxy headers and scheme detection (X-Forwarded-Proto, CF-Visitor, host headers).
  • Cookie and session gates that redirect based on state.
  • Mixed hostnames (www vs apex, multiple subdomains, internal origin hostnames).

The reason loops are common under Cloudflare is that you have at least two redirect authorities: the edge and the origin.

2. HTTP↔HTTPS Loops: Why They Happen

2.1 The Classic Contradiction

A typical loop looks like this:
Client requests http://example.com → Cloudflare redirects to https://example.com.
Origin receives https://example.com but believes the request is HTTP → origin redirects back to http://example.com.
Repeat.

The root cause is usually incorrect scheme detection at the origin. When an origin sits behind Cloudflare, it often relies on forwarded headers to know the real client scheme.

Common causes:

  • The origin app reads the connection scheme from the local socket (sees HTTP), instead of forwarded headers.
  • Missing or misread X-Forwarded-Proto / CF-Visitor headers.
  • A load balancer or reverse proxy between Cloudflare and origin overwrites scheme headers.
  • Application “force https” logic conflicts with Cloudflare’s HTTPS enforcement in an unexpected order.

2.2 Practical Fixes

Fix scheme detection first:

  • Ensure the origin trusts the correct forwarded headers.
  • Configure your reverse proxy / load balancer so it preserves scheme information.
  • In common frameworks, enable “proxy mode” or “trust proxy” settings so HTTPS is detected correctly.
  • Avoid double-enforcement: decide whether HTTPS enforcement is done at Cloudflare, at origin, or in one clear place.

A stable pattern is to enforce HTTPS at the edge and make sure the origin respects that as the canonical scheme.

3. Host Canonicalization Loops: www↔apex and Multi-Host Conflicts

3.1 The Most Common Host Loop

A classic host loop looks like:
https://example.com → redirect to https://www.example.com.
https://www.example.com → redirect to https://example.com.
Repeat.

This happens when:

  • Cloudflare has a forwarding rule to normalize host one way.
  • The origin framework has canonical host logic the other way.
  • A separate app layer (CDN plugin, CMS setting, middleware) also enforces host rules.
  • Multiple hostnames terminate at Cloudflare but map inconsistently to the same origin.

3.2 Practical Fixes

The fix is to establish a single canonical host decision and enforce it consistently:

  • Choose one canonical host (www or apex), and document it.
  • Enforce it in one layer, or ensure every layer enforces the same direction.
  • Remove conflicting redirects in the other layer(s).
  • Verify that origin-generated absolute URLs align with the canonical host; otherwise, users may be pushed back via links.

Also verify DNS and zone coverage:

  • Make sure both hostnames are correctly proxied and point to the intended origin.
  • Avoid accidental split-brain where one hostname is served by a different backend or different Cloudflare zone.

4. The Hidden Redirect Loop Factors Teams Miss

4.1 Cookies and Session Gates

Some apps redirect based on session state:

  • Redirect to login if the session cookie is missing.
  • Redirect to a consent page if a cookie is not set.
  • Redirect to a region/language host based on cookie values.

If cookies are not persisted across redirects—especially in distributed automation—you can get loops that look like canonicalization issues, but are actually state continuity failures.

4.2 Mixed Cache Variants

Redirect behavior can differ across variants:

  • Cached redirect for one variant, origin redirect for another.
  • Different edges with different cache state.
  • Query strings that create distinct cache keys and trigger different redirect chains.

If two requests “look identical” in code but differ in cookies, headers, or query ordering, you can see alternating redirect outcomes.

4.3 Different Workers Following Redirects Differently

In production pipelines, one worker may:

  • Drop cookies when following redirects.
  • Alter headers on redirected requests.
  • Follow or not follow 301/302 based on client settings.
  • Normalize URLs differently (trailing slashes, ports, query ordering).

This turns a deterministic redirect chain into inconsistent behavior that looks “random.”

5. A Practical Debugging Workflow

5.1 Capture the Redirect Chain

For one failing run, record:

  • Each URL visited in sequence.
  • Status code and Location header at each step.
  • The Host and scheme you requested.
  • The Cookie header sent, and Set-Cookie received.

You are looking for contradictions:

  • Scheme flips (http↔https).
  • Host flips (www↔apex).
  • Path normalization flips (/a↔/a/).
  • State gates repeating (login/consent redirect repeating).

5.2 Freeze Variables and Reproduce

To avoid confusion:

  • Use a pinned route and stable egress where possible.
  • Use one session context (cookie jar) for the entire chain.
  • Standardize request headers and query ordering.
  • Remove nonessential cookies, or keep them consistent if required.

If the loop disappears under frozen conditions, your root problem is drift—route switching, header variance, or cookie continuity—rather than a single misconfigured rule.

5.3 Fix One Authority at a Time

The most reliable way to eliminate loops:

  • Decide canonical scheme and canonical host.
  • Enforce those rules in one place, or ensure every place enforces the same direction.
  • Verify origin scheme detection behind Cloudflare.
  • Test with cache bypass, and with cache enabled, to ensure the same chain is produced.

6. Where CloudBypass API Fits

Redirect loops are often amplified by inconsistency: different routes, different edge locations, different session state, and uneven retry posture. Even after you fix the canonicalization logic, distributed execution can still recreate loops if redirects are followed with inconsistent cookies or headers.

CloudBypass API helps teams keep redirect handling stable in production by:

  • Task-level routing consistency, so a workflow does not change egress mid-chain.
  • Request state persistence, so cookies survive across redirects and retries.
  • Budgeted retries and controlled switching, so a loop does not become a dense retry storm.
  • Timing visibility, to identify where in the chain drift begins.

Cloudflare redirect loops are almost always caused by conflicting canonicalization logic across layers: Cloudflare vs origin, HTTP vs HTTPS enforcement, and www vs apex normalization. The fastest fix is to capture the full redirect chain, identify the contradiction, and then enforce one canonical scheme and host consistently, while ensuring the origin correctly detects HTTPS behind the proxy.

Once canonicalization is coherent and redirect handling is consistent across workers, loops stop appearing as random failures and become a solved configuration problem.

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