incident-responseoperational-runbookCDN

Emergency Playbook: What DevOps Should Do When Third-Party CDN Fails

bbinaries

2026-01-30

10 min read

Operational runbook for on-call and release engineers to preserve deploys during third-party CDN outages.

Hook: When a CDN outage stops your deploys and downloads, every minute counts

Third-party CDN failures in 2026 are no longer edge cases — they're an operational certainty for teams that rely on single-provider distribution. If your on-call or release engineer gets paged because artifacts won't download or a release can't be pulled, this playbook gives a prioritized, tactical runbook to preserve deploys, enable safe downloads, and reduce customer impact.

Executive summary (do this first)

Declare the incident & open the war room: page the release owner, on-call SRE, and the security lead.
Stop risky releases: put the release pipeline into hold/rollback mode.
Activate fallback hosting: switch artifact consumers to alternate origins or pre-signed cloud storage URLs.
Communicate early: update your internal channel and status page with an ETA window.
Capture timeline & evidence: preserve logs, request/response samples, DNS dig, and traceroutes for postmortem.

Why this matters in 2026

Late 2025 and early 2026 saw renewed high-impact outages across major edge and CDN providers, demonstrating that even well-architected internet plumbing can fail. Enterprises now adopt multi-CDN, SLSA-level build attestations, and automated artifact replication. This playbook assumes you already practice basic CI/CD hygiene and focuses on what to do when a third-party CDN fails and your deploys or artifact downloads are interrupted.

Runbook: Roles, channels, and severity levels

Who to call

Incident commander (IC): usually the on-call SRE or release manager.
Release owner: developer or release engineer who knows the artifact / pipeline.
Security/Compliance lead: for signed artifacts, credentials, and provenance checks.
Communications/Support: status page and customer messaging.

Channels to open

Privileged war-room (Zoom/Meet/Jabber) and a dedicated incident Slack/Teams thread.
Incident ticket in your tracking system (PagerDuty/ServiceNow/Jira Ops).
Public status page (Cache the message to avoid dependency on the failing provider).

Severity triage

S1: Production deploys blocked or downloads failing for most users.
S2: Build artifacts failing for internal CI but customer-facing downloads unaffected.
S3: Non-critical regressions; monitor and prepare fallback without halting releases.

Immediate technical triage (first 0–15 minutes)

Prioritize actions that restore downloads or prevent a bad release from reaching users.

1) Verify outage scope

# quick health checks
curl -I https://artifacts.example.com/latest.tar.gz
dig +short artifacts.example.com
traceroute artifacts.example.com

Check CDN status pages (Cloudflare, Fastly, Akamai, AWS CloudFront) and Twitter/X for provider updates. Note: provider status pages may be unreliable during large events — collect independent measurements (curl, dig, traceroute) from multiple regions. Keep a record for the incident postmortem and evidence collection.

2) Stop the release flow

If your pipelines still attempt to publish to the failing CDN, stop or pause them immediately. Most CI/CD systems let you pause or cancel a job; if not, disable the.publish step via a quick feature flag or environment toggle.

# example: GitHub Actions maintenance toggle
# Set a repo secret or env var that your publish job checks
gh secret set PUBLISH_PAUSED -b"true"

3) Enable direct origin downloads or pre-signed storage URLs

The fastest path is often bypassing the CDN and letting consumers download from cloud object storage or an origin server. Create time-limited pre-signed URLs and publish them on your internal channels and status page.

# AWS S3 presigned URL (example)
aws s3 presign s3://my-artifacts/releases/1.2.3/myapp.tar.gz --expires-in 3600

# GCS signed URL (example)
# using gcloud or client libraries

If artifacts are stored in a private registry (Maven, npm, PyPI, Docker), generate credentials or short-lived tokens that let clients pull directly from the registry backend. Consider offline-first field app patterns for CI runners that must continue in partitioned networks.

4) Flip DNS carefully — only if you already have preconfigured failover

If you have a multi-origin setup (multi-CDN or origins in different providers), use DNS failover or traffic steering. Be cautious: DNS changes propagate unpredictably, and TTLs matter.

# Example: Route53 change for DNS failover (pseudo)
aws route53 change-resource-record-sets --hosted-zone-id Z123 --change-batch file://failover.json

# Keep TTLs short during incidents (e.g., 60s) if you plan to flip often.

If you don't already have a secondary origin, creating one under pressure is risky. Prefer presigned URLs or a temporary signed origin proxy (see next section).

Temporary hosting patterns you can spin up fast

1) Temporary NGINX proxy on cloud VM

Use a small VM with an nginx proxy that serves artifacts from your origin or object storage. Use HTTPS with a provider-validated certificate and protect uploads via IP whitelisting.

# minimal nginx config
server {
  listen 80;
  server_name artifacts.example.com;

  location / {
    proxy_pass https://origin-bucket.s3.amazonaws.com/;
    proxy_set_header Host $host;
  }
}

2) Upload artifacts to cloud object storage (S3/GCS) and presign

If your artifacts are already in CI, add a parallel publish step to upload to a cloud bucket and create a presigned URL; then post that URL to the status page and internal channels.

# quick upload + presign example
aws s3 cp build/output/myapp.tar.gz s3://incident-fallback/releases/1.2.3/
aws s3 presign s3://incident-fallback/releases/1.2.3/myapp.tar.gz --expires-in 7200

3) Local registry cache / proxy for package managers (npm, pip, Maven)

If downloads for package managers fail, run a local proxy like Verdaccio for npm or use devpi for pip. Configure CI agents to use the proxy; this mirrors the benefits of offline-first caches and lightweight edge nodes.

# npm fallback
npm set registry https://verdaccio.internal:4873

# pip fallback
pip install --index-url https://devpi.internal/root/pypi/+simple/ package

Package manager-specific quick fixes

npm / Yarn

Short-term: switch registry using npm config or .npmrc.
Long-term: run a local cache (Verdaccio) and configure CI runners to use it.

pip

Temporarily use --index-url to point to a mirror or your internal devpi instance.
Consider vendorizing critical wheels in your artifact bucket for emergency installs.

Maven / Gradle

Add an alternate mirror in settings.xml or build.gradle that points to a proxied Nexus/Artifactory snapshot.
Pre-stage release artifacts to multiple blob stores to avoid a single-hosting failure.

Docker / Container images

Pull from an alternate registry (mirror) or keep a minimal on-prem cache of base images.
Use an OCI distribution tool (ORAS) to copy images across registries as part of your incident process.

CI/CD tactics during CDN failure

Your CI/CD system should let you block or redirect publishing artifacts. Here are practical actions:

Pause publish jobs: set a pipeline variable or secret so publish steps fail safe.
Redirect artifacts: add a conditional path to upload artifacts to an alternate bucket or registry.
Gate deployments: use feature flags or progressive rollouts to cut blast radius until distribution is verified.

# GitHub Actions snippet: conditional publish
jobs:
  publish:
    if: env.PUBLISH_PAUSED != 'true'
    runs-on: ubuntu-latest
    steps: ...

Communication templates and cadence

Clear, frequent updates reduce customer friction. Use the same message across internal and external channels but adjust details.

Public status update (example):
We are currently experiencing issues delivering downloads due to a third-party CDN outage. We have paused new releases and enabled direct-download URLs for critical artifacts. Estimated resolution: TBC. Updates every 30 minutes.

Internally, share the technical mitigation steps, who owns each action, and where to find presigned URLs or alternate registries.

Security & provenance during emergency steps

Do not trade security for speed. When you bypass CDN protections, enforce artifact signing and provenance checks. In 2026, most organizations have adopted sigstore/cosign for signing and SLSA attestations for CI builds. If you must publish temporary URLs, include checksums and signatures in the status message. Consider documenting these checks alongside your multimodal media workflows and provenance playbooks so validation steps are repeatable.

# Verify cosign signature (example)
cosign verify --key cosign.pub github.com/myorg/myrepo@sha256:...

Evidence collection for the postmortem (do this now)

Save all CDN provider status pages and incident IDs.
Collect curl responses and headers (including Via/Server headers) from multiple regions.
DNS dig + traceroute output from multiple vantage points.
CI job logs showing publish attempts and failures.
Audit logs of any DNS changes, IAM actions, or bucket uploads made during the incident.

Recovery & restore (30–120 minutes)

Verify the CDN provider has restored service across regions.
Gradually switch traffic back to the primary CDN using low-TTL DNS and health checks.
Ensure cached artifacts and edge nodes are warmed so downloads don't spike origin load.
Re-enable paused pipelines and watch for failed publishes; reconcile any duplicate artifact versions.

Post-incident: analysis and long-term mitigations

Use the incident as a chance to harden distribution and release processes. Recommended actions:

Multi-CDN strategy: adopt two providers with automatic health-based steering or manual failover tested quarterly. Evaluate anycast, edge-first approaches and traffic steering as part of that design.
Artifact replication: replicate signed artifacts to at least two cloud object stores and one internal registry.
Local caches: run lightweight caches for package managers on CI agents or colocated with compute regions.
Provenance & signing: enforce signed artifacts (cosign/sigstore) and store SBOMs and attestations alongside binaries.
Runbook drills: simulate CDN failures during game days; validate DNS failover, presigned URL issuance, and rollback procedures. Combine these with safe chaos engineering practices to avoid destructive tests.
Monitoring & SLOs: measure artifact download latency and success rate as an SLO; alert before user-visible failures.

Example postmortem checklist

Timeline: record start, mitigation actions, and recovery timestamps.
Root cause analysis: provider root cause vs. your configuration.
Impact: number of blocked deploys, failed downloads, SLO breaches.
Corrective actions: prioritized backlog items with owners and due dates.
Follow-up: schedule a multi-CDN test and artifact replication run within 30 days.

Practical scripts and snippets you can add to your playbook

Use these as templates to automate steps the next time you face a CDN failure.

# Minimal presign-and-publish script (bash)
ARTIFACT=build/myapp.tar.gz
BUCKET=incident-fallback
aws s3 cp "$ARTIFACT" s3://$BUCKET/releases/$(date +%s)/
URL=$(aws s3 presign s3://$BUCKET/releases/$(date +%s)/myapp.tar.gz --expires-in 7200)
echo "Emergency download URL: $URL"
# Post to internal status page or Slack using existing webhook

Case study (brief): How a release team preserved deploys during a Jan 2026 edge outage

In January 2026 a major edge provider experienced a regional outage that disrupted artifact downloads for multiple customers. One mid-sized company's release team declared an incident, paused a hotfix publish, and executed the following: generated presigned S3 URLs for the hotfix artifacts, published them to the status page and support channel, and shifted CI to upload all subsequent artifacts to a secondary bucket. They verified the client checksums and cosign signatures before re-enabling the release. Post-incident, they added an automated ORAS replication job to copy artifacts to two registries and added an option in their CI to toggle publish targets.

"Assume it will happen again. The only question is how fast your team can switch to a secure fallback." — SRE lead, 2026

Advanced strategies and 2026 trends to adopt now

Automated multi-origin publishing: CI pipelines that publish to a canonical artifact store and replicate asynchronously to multiple CDNs and object stores.
Edge compute for auth: use edge authorization patterns and edge-hosted functions to validate requests and issue short-lived download tokens even if the CDN control plane is degraded.
Provenance-first artifacts: include SBOMs and in-toto attestations with every release so clients can validate integrity irrespective of where artifacts are served.
Policy-based routing: use traffic steering (anycast + DNS + BGP) with health checks to fail over traffic without global TTL churn.

Actionable takeaways — what to do after reading this

Draft an incident-specific playbook that maps to your CI/CD, registries, and package managers.
Implement at least one fast fallback (presigned object storage + local package proxy) and test it during a game day.
Automate artifact signing and store attestations alongside binaries so security checks remain valid during failover.
Run quarterly failover drills that include DNS flips, CDN failover, and staged release resumption.

Call to action

Ready to stop single-CDN risk from blocking your deploys? Start by building the emergency workflows above into your CI/CD pipeline and testing them in a controlled drill. If you want a jump-start, download our Incident Playbook template and a prebuilt set of CI snippets that add automated multi-origin publish and signed artifact replication to your pipeline. Visit binaries.live/playbooks to get the toolkit and schedule a 1:1 readiness review with our release-engineering experts.

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