OfflineImage YAML Specification

potctl allows users to deploy container images to edge nodes that cannot access the internet for pulling images. OfflineImage enables developers to pull images on their local machine with potctl installed, then transfer and load those images on remote edge hosts via SSH, automatically creating catalog items with registry ID 2 (from_cache).

OfflineImage Definition

---
apiVersion: datasance.com/v3
kind: OfflineImage
metadata:
  name: alpine-offline
spec:
  x86: alpine:latest
  arm: alpine:latest
  auth: 
    username: foo
    password: bar
  agent:
    - edge-1
    - edge-2
    - edge-3

Field Specifications

Field	Description
metadata.name	Unique name for the offline image resource
spec.x86	Docker image tag for x86/amd64 architecture (e.g., alpine:latest)
spec.arm	Docker image tag for ARM architecture (e.g., alpine:latest)
spec.auth	(Optional) Authentication credentials for pulling images from private registries
spec.auth.username	Username for registry authentication
spec.auth.password	Password or authentication token for registry authentication
spec.agent	List of agent names where the image should be transferred and loaded

Deployment

Deploy an OfflineImage using potctl:

potctl deploy -f offline-image.yaml

Command Flags

Flag	Description
--no-cache	Disable caching for OfflineImage images after download
--transfer-pool int	Maximum number of concurrent OfflineImage transfers (default: 2)

Example Usage

# Deploy with default settings (2 concurrent transfers, caching enabled)
potctl deploy -f offline-image.yaml

# Deploy without caching images after download
potctl deploy -f offline-image.yaml --no-cache

# Deploy with custom transfer pool size
potctl deploy -f offline-image.yaml --transfer-pool 4

How It Works

1. Image Pull: potctl pulls the specified Container images (x86 and/or arm) on the developer's local machine from the configured registry.
2. Image Transfer: The pulled images are transferred to the specified edge agents via SSH using the agent's SSH configuration.
3. Image Load: The images are loaded into Docker/Podman on each remote edge host.
4. Catalog Creation: potctl automatically creates catalog items with registry ID 2 (from_cache) so the images can be used by microservices on those edge nodes.

This feature is essential for edge deployments in air-gapped or network-restricted environments where edge nodes cannot directly access container registries.

Use Cases

• Air-gapped Edge Nodes: Deploy images to edge nodes that are isolated from the internet
• Network-Restricted Environments: Transfer images to edge nodes behind firewalls or with limited network access
• Offline Deployments: Pre-load images on edge infrastructure before deployment
• Bandwidth Optimization: Transfer images once and reuse them across multiple microservices

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