X-Cache-Miss-From

When a CDN cache node fails to find a stored copy of a resource, the X-Cache-Miss-From unofficial response header records which specific node or pod triggered the origin fetch.

Table of Contents

Usage

When a CDN or reverse proxy fails to find a cached copy of a resource, some systems emit X-Cache-Miss-From to record which specific node or pod had to reach back to origin. The value is typically a server or Kubernetes pod identifier such as parking-7968547645-84pss or parking-7bf6ddfb95-nk5lt.

This header surfaces the physical or logical layer where the miss occurred. In multi-tier cache architectures, a miss at one layer triggers a fetch from the next layer or from origin. Knowing which node missed helps operators pinpoint cold cache nodes, identify uneven cache distribution across pods, and trace the path a cache miss took through the infrastructure.

The header complements X-Cache, which reports the miss status, by adding the identity of the node responsible. Where X-Cache-Hits counts how many times a cached resource was served, X-Cache-Miss-From records the opposite: the node with an empty cache.

Note

The "X-" naming convention for HTTP headers, "X" referring to "experimental", has been deprecated and needs to be transitioned to the formal naming convention for HTTP headers.

Values

The value is a server or pod name assigned by the hosting infrastructure. Kubernetes-based deployments commonly produce identifiers following patterns like:

  • parking-7968547645-84pss: a pod name with a replicaset hash and pod hash suffix
  • parking-7bf6ddfb95-nk5lt: another pod in the same deployment

The format is deployment-specific and carries no standardized structure. The strings are meaningful to the infrastructure team and are intended for log correlation and debugging rather than client interpretation.

Example

A Kubernetes-hosted CDN edge returns X-Cache-Miss-From alongside a MISS from X-Cache-Status. The pod identifier tells the operator which replica had an empty cache for this resource.

X-Cache: MISS
X-Cache-Miss-From: parking-7968547645-84pss

When multiple cache layers are active, the value pinpoints the layer triggering the origin fetch. The pod name below corresponds to a different replica than the one serving the response, indicating the miss occurred at an intermediate cache tier.

X-Cache: MISS
X-Cache-Miss-From: parking-7bf6ddfb95-nk5lt

See also

Last updated: April 4, 2026