Registry push & pull
A registry doesn't move images whole. An image is a manifest — a list of layers — plus the layers, and push and pull transfer only the layers the other side is missing. Each layer is identified by a content hash (its digest), so uploading many images built on the same base still stores that base layer exactly once.
01 Concept at a Glance
Interactive Step-by-StepA registry doesn't move images as a single blob. An image is a manifest — a list of layers — plus the layers themselves.
02 Understand It Simply
For EveryoneRather than photocopying a whole book, you send the table of contents (the manifest) first, skip the chapters they already have, and post only the missing ones.
push sends the manifest's layer digests to find out which layers already exist, then uploads only the rest.
pull does the same in reverse, fetching only what's missing locally.
From the second deploy on, typically just the app layer moves.
Because digests are content-based, different tags with identical contents resolve to the same layer.
- –Cutting CI/CD deploy times
- –pinning releases by tag or digest
- –running a private registry
- –and ordering layers to reduce transfer size
03 Frequently Asked Questions
FAQWhat is Registry push & pull?+
A registry doesn't move images whole. An image is a manifest — a list of layers — plus the layers, and push and pull transfer only the layers the other side is missing. Each layer is identified by a content hash (its digest), so uploading many images built on the same base still stores that base layer exactly once.
Where is Registry push & pull used?+
Cutting CI/CD deploy times, pinning releases by tag or digest, running a private registry, and ordering layers to reduce transfer size.
What's a simple analogy for Registry push & pull?+
Rather than photocopying a whole book, you send the table of contents (the manifest) first, skip the chapters they already have, and post only the missing ones.