Documentation Index
Fetch the complete documentation index at: https://radarhq.io/docs/llms.txt
Use this file to discover all available pages before exploring further.
This document covers Radar’s cluster connection behavior. For CLI flags and basic usage, see the README.
Persistent Configuration
Radar stores configuration in two files under ~/.radar/:
Config File (~/.radar/config.json)
Persistent defaults for CLI flags. CLI flags always override these values. Managed via the Settings dialog in the UI or PUT /api/config.
{
"kubeconfig": "",
"kubeconfigDirs": [],
"namespace": "",
"port": 9280,
"noBrowser": false,
"timelineStorage": "memory",
"timelineDbPath": "~/.radar/timeline.db",
"historyLimit": 10000,
"prometheusUrl": "",
"mcp": true
}
| Field | Description |
|---|
kubeconfig | Path to kubeconfig file (same as --kubeconfig) |
kubeconfigDirs | Directories containing kubeconfig files (same as --kubeconfig-dir) |
namespace | Initial namespace filter |
port | Server port (default 9280) |
noBrowser | Don’t auto-open browser |
timelineStorage | memory or sqlite |
timelineDbPath | Path to SQLite database |
historyLimit | Max timeline events to retain |
prometheusUrl | Manual Prometheus/VictoriaMetrics URL - skips auto-discovery. Useful when Prometheus is not in the same cluster or uses a non-standard service name. |
mcp | Enable/disable MCP server for AI tools (default: enabled) |
Settings File (~/.radar/settings.json)
User preferences for the UI. Managed via the Settings dialog or PUT /api/settings.
{
"theme": "system",
"pinnedKinds": [
{ "name": "Deployments", "kind": "Deployment", "group": "" }
]
}
| Field | Values | Description |
|---|
theme | light, dark, system | UI theme preference |
pinnedKinds | Array of {name, kind, group} | Resource kinds pinned to the sidebar |
Cluster Connection Precedence
Radar connects to Kubernetes clusters using the same configuration sources as kubectl:
| Priority | Source | Description |
|---|
| 1 | --kubeconfig flag | Explicit path to kubeconfig file |
| 2 | KUBECONFIG env var / --kubeconfig-dir flag | Either can provide kubeconfig(s); mutually exclusive alternatives |
| 3 | In-cluster config | Automatic when running inside a Kubernetes pod (KUBERNETES_SERVICE_HOST is set) |
| 4 | ~/.kube/config | Default kubeconfig location |
KUBECONFIG vs In-Cluster Detection
When Radar runs inside a Kubernetes pod, Kubernetes automatically sets the KUBERNETES_SERVICE_HOST environment variable. This normally triggers in-cluster configuration using the pod’s service account credentials.
However, explicit kubeconfig takes precedence. If you set KUBECONFIG or pass --kubeconfig, Radar uses that instead of in-cluster config. This allows you to:
- Run Radar inside a pod but connect to a different cluster
- Use specific credentials instead of the pod’s service account
- Test with a custom kubeconfig while developing inside a cluster
Example: Override in-cluster config
# Inside a pod, connect to a different cluster
export KUBECONFIG=/path/to/other-cluster.yaml
kubectl radar
kubectl and follows the Kubernetes client-go precedence rules.
Multiple Kubeconfig Files
KUBECONFIG can contain multiple file paths (colon-separated on Linux/macOS, semicolon-separated on Windows). Radar merges these files following Kubernetes conventions:
export KUBECONFIG=~/.kube/config:~/.kube/staging-config:~/.kube/prod-config
kubectl radar
--kubeconfig-dir to load all kubeconfig files from a directory:
kubectl radar --kubeconfig-dir ~/.kube/configs/
Context Switching
Radar supports switching between Kubernetes contexts at runtime through the UI. Click the context selector in the header to switch between available contexts.
When running in-cluster (using the pod’s service account), context switching is disabled.
