Traefik Mesh mTLS Certificate Rotation and Secret Synchronization

Traefik Mesh implements a zero-trust architecture by utilizing a central Certificate Authority (CA) to distribute identities to sidecar proxies via Kubernetes secrets. This mechanism ensures that mutual TLS (mTLS) is enforced for all inter-service communication based on SPIFFE-like identity standards.

A critical requirement for maintaining mesh security is the seamless rotation of these certificates without interrupting active traffic flows. However, there is uncertainty regarding how the sidecar proxies detect updates to the underlying Kubernetes secrets and the specific trigger that forces a reload of the trust bundle without restarting the proxy container.

If NetworkPolicies are strictly enforced to limit control plane access, the synchronization of these updated identities may be delayed or blocked.

• What is the internal mechanism Traefik Mesh uses to signal sidecars to refresh certificates from Kubernetes secrets?
• How does the mesh ensure atomic updates to the CA root certificate across all nodes to prevent validation failures during a rotation window?