Skip to main content
Career Paths
Concepts
Istio Mtls Strict Permissive
The Simplified Tech

Role-based learning paths to help you master cloud engineering with clarity and confidence.

Product

  • Career Paths
  • Interview Prep
  • Scenarios
  • AI Features
  • Cloud Comparison
  • Resume Builder
  • Pricing

Community

  • Join Discord

Account

  • Dashboard
  • Credits
  • Updates
  • Sign in
  • Sign up
  • Contact Support

Stay updated

Get the latest learning tips and updates. No spam, ever.

Terms of ServicePrivacy Policy

© 2026 TheSimplifiedTech. All rights reserved.

BackBack
Interactive Explainer

Istio mTLS Modes: STRICT vs PERMISSIVE

PeerAuthentication modes for Istio mTLS migration: PERMISSIVE (gradual rollout) to STRICT (enforce mTLS everywhere).

🎯Key Takeaways
PERMISSIVE: accepts both plaintext and mTLS (migration)
STRICT: requires mTLS (production security)
Migrate gradually: namespace-by-namespace or workload-by-workload

Istio mTLS Modes: STRICT vs PERMISSIVE

PeerAuthentication modes for Istio mTLS migration: PERMISSIVE (gradual rollout) to STRICT (enforce mTLS everywhere).

~1 min read
Be the first to complete!
What you'll learn
  • PERMISSIVE: accepts both plaintext and mTLS (migration)
  • STRICT: requires mTLS (production security)
  • Migrate gradually: namespace-by-namespace or workload-by-workload

Migration Strategy

Migration path: 1. Start PERMISSIVE (accept both plaintext and mTLS). 2. Inject sidecars incrementally. 3. Monitor with Kiali to see non-mTLS traffic. 4. Switch namespace to STRICT once all services have sidecars. STRICT mode rejects plaintext — use this in production for zero-trust networking.

Key takeaways

  • PERMISSIVE: accepts both plaintext and mTLS (migration)
  • STRICT: requires mTLS (production security)
  • Migrate gradually: namespace-by-namespace or workload-by-workload

Related concepts

Explore topics that connect to this one.

  • Istio mTLS Encryption Deep Dive
  • Istio Authorization Policies
  • Istio Certificate Management & SPIFFE

Suggested next

Often learned after this topic.

Istio Authorization Policies

Ready to see how this works in the cloud?

Switch to Career Paths for structured paths (e.g. Developer, DevOps) and provider-specific lessons.

View role-based paths

Sign in to track your progress and mark lessons complete.

Continue learning

Istio Authorization Policies

Discussion

Questions? Discuss in the community or start a thread below.

Join Discord

In-app Q&A

Sign in to start or join a thread.