Is LaunchDarkly Down? How to Tell and What to Do

Is LaunchDarkly Down? How to Tell and What to Do

LaunchDarkly is the feature flag management layer for teams running continuous delivery. When LaunchDarkly goes down, your SDKs fall back to cached or default flag values — which means features may silently activate or deactivate for all users without any intentional release.

The fastest way to know: Statusfield monitors LaunchDarkly continuously and alerts you within minutes. Without external monitoring, a LaunchDarkly outage can cause unexpected behavior changes across your product that look like bugs in your code.

Common Signs of a LaunchDarkly Outage

How to Confirm It's LaunchDarkly, Not Your SDK

1. Check LaunchDarkly's streaming endpoint

LaunchDarkly SDKs connect to a streaming endpoint to receive real-time flag updates. A degradation here means flags won't update even if the dashboard shows changes.

curl -I "https://stream.launchdarkly.com/all" \
  -H "Authorization: YOUR_SDK_KEY"

A connection timeout or 5xx confirms the streaming infrastructure is degraded.

2. Test the REST API

curl "https://app.launchdarkly.com/api/v2/flags/default" \
  -H "Authorization: YOUR_ACCESS_TOKEN"

A 503 or 429 (unusual rate limiting) confirms API-level issues.

3. Check SDK initialization logs

Most LaunchDarkly SDKs log initialization status. Look for:

• "Streaming connection failed"
• "Using cached flag values"
• "SDK failed to connect"

If you see these during normal operation, your SDK is operating in degraded mode.

4. Try a direct flag evaluation

const flagValue = ldClient.variation("my-flag", userContext, false);

If you're getting the fallback false for all users when your dashboard shows the flag enabled, the SDK is not receiving current flag state from LaunchDarkly.

The Impact of LaunchDarkly Outages on Your Product

LaunchDarkly outages are particularly tricky to diagnose because the system is designed to degrade gracefully — SDKs fall back to cached values or default values. This means:

• Features may silently change state: If the cache is empty (first deployment) and LaunchDarkly is down, all flags return defaults — which may differ from your intended rollout state.
• Experiments stop collecting data: A/B test flag evaluations during an outage produce unreliable experiment data.
• Staged rollouts freeze: A gradual rollout that was progressing will stop advancing until connectivity recovers.
• Kill switches don't work: If you rely on a flag to disable a broken feature, that kill switch won't fire reliably during a LaunchDarkly outage.

Statusfield monitors LaunchDarkly so you know immediately when flag delivery is compromised — before your on-call team starts chasing a bug that's actually a feature flag state change.

What to Do During a LaunchDarkly Outage

Immediate (first 5 minutes)

1. Determine what state your flags are in — check your SDK logs to understand whether it's using cached values or defaults. This tells you what behavior your users are experiencing.
2. Identify any kill switches or high-risk flags — if you have a kill switch for a new feature that's in production, confirm it's in the right state in cache. If not, prepare to deploy a code-level disable.
3. Pause any active staged rollouts — LaunchDarkly won't advance percentage rollouts while disconnected from the backend.
4. Alert your release team — any planned deploys that depend on flag changes should be held until connectivity recovers.

Communication (first 15 minutes)

• Notify your engineering team of the LaunchDarkly outage so no one spends time debugging flag behavior as a code bug.
• If user-facing behavior has changed due to fallback flag values, assess whether it requires a customer communication.
• Hold any feature releases that depend on LaunchDarkly for the rollout mechanism.

Recovery

• After LaunchDarkly recovers, verify that all SDKs reconnected and are receiving current flag state (check SDK logs for "streaming connection re-established").
• Review any experiments running during the outage — the data from the degraded window is likely unreliable.
• Confirm staged rollouts are at the expected percentage and have not reset.

LaunchDarkly Components and What Each Outage Looks Like

Why DIY Flag Monitoring Misses Degraded Delivery

Checking whether your application is running isn't enough to know if LaunchDarkly is healthy:

• Graceful fallback hides the problem: A well-configured SDK looks healthy even when disconnected — it just uses cached or default values silently.
• No error in your application logs: Unless you've explicitly instrumented SDK connection state, your application logs won't reflect a LaunchDarkly connectivity issue.
• The dashboard may work while delivery is degraded: The LaunchDarkly web UI can be available while the streaming delivery infrastructure for SDKs is down — you can change flags but they won't propagate.

Effective LaunchDarkly monitoring checks the streaming endpoint health, not just application availability.

Monitor LaunchDarkly Before a Flag State Change Becomes an Incident

Statusfield monitors LaunchDarkly and 1,700+ other services continuously. When LaunchDarkly degrades, you get alerted immediately — before your on-call team starts debugging unexpected feature behavior caused by a silent flag fallback.

3 monitors, 10 alerts/month, no credit card required.

FAQ

Is LaunchDarkly down right now?

Statusfield monitors LaunchDarkly continuously. If flags aren't updating or your SDK logs show connection errors, check Statusfield for real-time LaunchDarkly status.

Why are my feature flags returning default values for everyone?

All-users-returning-default is the classic sign of an SDK that's lost its streaming connection to LaunchDarkly. Check SDK logs for "streaming connection failed" — if you see it, LaunchDarkly is the problem, not your code. Monitor LaunchDarkly via Statusfield to get alerted immediately when this happens.

How long do LaunchDarkly outages last?

Most incidents resolve within 30 minutes to 2 hours. Check Statusfield for live status updates.

How do I get alerted when LaunchDarkly goes down?

Statusfield monitors LaunchDarkly and fires alerts the moment it detects a degradation. Every plan starts with a free trial — no credit card required.