{
  "type": "excalidraw",
  "version": 2,
  "source": "https://excalidraw.com",
  "elements": [
    {
      "type": "text", "version": 1, "id": "title",
      "x": 150, "y": 16, "width": 600, "height": 24,
      "angle": 0, "strokeColor": "#1a1a1a", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 1, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "fontSize": 20, "fontFamily": 1,
      "text": "Ephemeral debug sidecar — gdb without rebuilding the prod image",
      "textAlign": "center", "verticalAlign": "middle"
    },
    {
      "type": "rectangle", "version": 1, "id": "shared-ns-RED",
      "x": 40, "y": 80, "width": 820, "height": 280,
      "angle": 0, "strokeColor": "#c0392b", "backgroundColor": "#fdfbf7",
      "fillStyle": "solid", "strokeWidth": 2, "strokeStyle": "dashed",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "roundness": { "type": 3 }
    },
    {
      "type": "text", "version": 1, "id": "shared-ns-label-RED",
      "x": 60, "y": 88, "width": 780, "height": 18,
      "angle": 0, "strokeColor": "#c0392b", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 1, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "fontSize": 12, "fontFamily": 1,
      "text": "shared PID namespace  —  containers see each other's processes  —  --pid=container:main",
      "textAlign": "center", "verticalAlign": "middle"
    },
    {
      "type": "rectangle", "version": 1, "id": "main",
      "x": 80, "y": 120, "width": 340, "height": 220,
      "angle": 0, "strokeColor": "#4a73b8", "backgroundColor": "#e8f0fb",
      "fillStyle": "solid", "strokeWidth": 1.5, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": ["main-group"],
      "roundness": { "type": 3 }
    },
    {
      "type": "text", "version": 1, "id": "main-content",
      "x": 100, "y": 130, "width": 300, "height": 200,
      "angle": 0, "strokeColor": "#1a1a1a", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 1, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": ["main-group"],
      "fontSize": 12, "fontFamily": 1,
      "text": "Main container  —  production\nstripped, no debug tools, smallest image\n\nPID 1: your C++ service\n/usr/local/bin/myservice\nUBI micro base, ~26 MB total\n\nContainerfile:\n  FROM ubi-micro\n  COPY --from=build /app /\n  ENTRYPOINT [\"/app\"]",
      "textAlign": "center", "verticalAlign": "top"
    },
    {
      "type": "rectangle", "version": 1, "id": "sidecar",
      "x": 480, "y": 120, "width": 340, "height": 220,
      "angle": 0, "strokeColor": "#b86742", "backgroundColor": "#ecdfd8",
      "fillStyle": "solid", "strokeWidth": 1.5, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": ["sidecar-group"],
      "roundness": { "type": 3 }
    },
    {
      "type": "text", "version": 1, "id": "sidecar-content",
      "x": 500, "y": 130, "width": 300, "height": 200,
      "angle": 0, "strokeColor": "#1a1a1a", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 1, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": ["sidecar-group"],
      "fontSize": 12, "fontFamily": 1,
      "text": "Debug sidecar  —  ephemeral\nheavy, only running during a debug session\n\ngdb + debug symbols + glibc-debug\neu-stack, valgrind, strace, perf\n~400 MB image, fine for ad-hoc use\n\nLaunch command:\n  podman run -it --rm \\\n    --pid=container:main \\\n    --cap-add=SYS_PTRACE  debug:latest",
      "textAlign": "left", "verticalAlign": "top"
    },
    {
      "type": "arrow", "version": 1, "id": "arrow-ptrace-RED",
      "x": 500, "y": 210, "width": -100, "height": 0,
      "angle": 0, "strokeColor": "#c0392b", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 2, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "points": [ [0, 0], [-100, 0] ], "endArrowhead": "arrow"
    },
    {
      "type": "text", "version": 1, "id": "ptrace-label-RED",
      "x": 410, "y": 196, "width": 80, "height": 14,
      "angle": 0, "strokeColor": "#c0392b", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 1, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "fontSize": 11, "fontFamily": 1,
      "text": "gdb attach PID 1\nvia ptrace",
      "textAlign": "center", "verticalAlign": "middle"
    },
    {
      "type": "rectangle", "version": 1, "id": "flag-band-RED",
      "x": 60, "y": 386, "width": 780, "height": 50,
      "angle": 0, "strokeColor": "#c0392b", "backgroundColor": "#fdfbf7",
      "fillStyle": "solid", "strokeWidth": 1.5, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "roundness": { "type": 3 }
    },
    {
      "type": "text", "version": 1, "id": "flag-band-label-RED",
      "x": 80, "y": 394, "width": 740, "height": 36,
      "angle": 0, "strokeColor": "#1a1a1a", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 1, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "fontSize": 12, "fontFamily": 1,
      "text": "The two flags that make this work:\n--pid=container:main   joins the main container's PID namespace  |  --cap-add=SYS_PTRACE   allows ptrace attach",
      "textAlign": "left", "verticalAlign": "middle"
    },
    {
      "type": "text", "version": 1, "id": "workflow",
      "x": 60, "y": 458, "width": 780, "height": 80,
      "angle": 0, "strokeColor": "#1a1a1a", "backgroundColor": "transparent",
      "fillStyle": "solid", "strokeWidth": 1, "strokeStyle": "solid",
      "roughness": 1, "opacity": 100, "groupIds": [],
      "fontSize": 11, "fontFamily": 1,
      "text": "Workflow:\n1. prod container is running normally (no debugger present)\n2. you notice an issue → spawn the sidecar with the flags above\n3. gdb attach in sidecar, debug interactively, exit sidecar → prod container untouched",
      "textAlign": "left", "verticalAlign": "top"
    }
  ],
  "appState": { "viewBackgroundColor": "#fdfbf7", "gridSize": null },
  "files": {}
}