docs(keycloak-session-store): import the session-storage lab as a new project

The keycloak project ended with four open questions that design could not settle. A two-VM lab was built to answer them by measurement, and this is that material: 26 experiments, 125 raw command outputs, 22 browser captures. Follows the import procedure in README.md. source/ the originating repository verbatim — 78 documents, 28 SVGs, 8 manifests, plus .source-revision recording the commit final/ the SSOT document.md 729 lines written from the 29 experiment documents, not concatenated: what was predicted, what was measured, and where the measurement itself was wrong evidence/raw 125 outputs, flattened to <experiment>__<file> because the originals collided (01-baseline.txt appeared three times) and the audit only globs the top level evidence/meta one per raw file; command and exitCode are null and the README says why rather than inventing them evidence/browser 22 captures assets/ three diagrams through techviz .techviz/ their VizSpecs A separate project rather than an addition to keycloak: the B-layer answers that project's four questions, but the A, C and D layers are about cluster failure, SSO and operations, and one document.md should hold one subject. The four question records there can point here through 관계. Recorded rather than papered over: only three of the 28 diagrams were remade. The repository forbids hand-drawn SVG and forbids titles inside the canvas; all 28 originals carry both, so converting them is redrawing, not reformatting. They stay in source/ and the gap is written into the document. verify-pipeline.py passes. audit-records.py reports no issues. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-04 22:51:59 +09:00
parent 43bccd08a8
commit b2963105a8
5017 changed files with 372751 additions and 4943 deletions
@@ -0,0 +1,23 @@
+# 세션 공유가 실제로 지나는 경로
+
+## Alternative text
+
+keycloak-0 과 keycloak-1 이 각자 캐시를 갖고 PostgreSQL 을 함께 읽는 구성. 두 캐시 사이에는 세션 복제 경로가 없다.
+
+## Long description
+
+keycloak-0 과 keycloak-1 은 JGROUPS_PING 테이블을 통해 서로를 발견하고 클러스터 뷰를 형성한다. 그러나 sessions 캐시의 엔트리는 노드 사이로 복제되지 않으며, 각 노드는 자기가 처리한 로그인만 캐시한다. 노드 A 로 로그인한 세션을 노드 B 가 아는 이유는 노드 B 가 PostgreSQL 의 OFFLINE_USER_SESSION 을 직접 읽기 때문이고, 이는 반대편 노드가 날린 SQL 을 문장 로깅으로 잡아 확인했다.
+
+## Elements and evidence
+
+- **keycloak-0** (service): 로그인을 처리하고 자기 sessions 캐시에만 엔트리를 남긴다. Evidence: L49–L51.
+- **PostgreSQL** (datastore): OFFLINE_USER_SESSION 에 세션 행을 보관한다. 두 노드가 같은 행을 본다. Evidence: L48–L52.
+- **keycloak-1** (service): 다른 노드가 만든 세션을 캐시로 받지 않고 데이터베이스에서 읽는다. Evidence: L48–L51.
+- **JGROUPS_PING** (datastore): 노드가 서로를 발견하는 자리. 여기 등록되어 있다는 것과 세션이 복제된다는 것은 다른 사건이다. Evidence: L44–L46.
+
+## Relationships
+
+- **keycloak-0 → JGROUPS_PING:** 멤버 등록. Evidence: L44–L45.
+- **keycloak-0 → PostgreSQL:** 세션 INSERT. Evidence: L49–L52.
+- **keycloak-1 → JGROUPS_PING:** 멤버 등록. Evidence: L44–L45.
+- **keycloak-1 → PostgreSQL:** 세션 SELECT. Evidence: L48–L50.
@@ -0,0 +1,19 @@
+# 세션 공유가 실제로 지나는 경로
+# Question: 두 Keycloak 노드가 같은 세션을 아는 것은 무엇 때문인가
+direction: right
+n0: "keycloak-0" {
+  shape: rectangle
+}
+n1: "PostgreSQL" {
+  shape: cylinder
+}
+n2: "keycloak-1" {
+  shape: rectangle
+}
+n3: "JGROUPS_PING" {
+  shape: cylinder
+}
+n0 -> n1: "세션 INSERT"
+n2 -> n1: "세션 SELECT"
+n0 -> n3: "멤버 등록"
+n2 -> n3: "멤버 등록"
@@ -0,0 +1,13 @@
+digraph techviz {
+  graph [rankdir=LR, splines=ortho, nodesep=0.55, ranksep=0.85];
+  node [fontname=Helvetica, fontsize=11, margin="0.18,0.12", style="rounded,filled", fillcolor=white, color="#2d4357", penwidth=1.5];
+  edge [fontname=Helvetica, fontsize=10, color="#364b5f", penwidth=1.4, arrowsize=0.75];
+  n0 [label="keycloak-0", shape=box, style="rounded,filled"];
+  n1 [label="PostgreSQL", shape=cylinder, style="rounded,filled"];
+  n2 [label="keycloak-1", shape=box, style="rounded,filled"];
+  n3 [label="JGROUPS_PING", shape=cylinder, style="rounded,filled"];
+  n0 -> n1 [label="세션 INSERT", style=solid];
+  n2 -> n1 [label="세션 SELECT", style=solid];
+  n0 -> n3 [label="멤버 등록", style=solid];
+  n2 -> n3 [label="멤버 등록", style=solid];
+}
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<mxfile host="app.diagrams.net" modified="2026-07-23T00:00:00.000Z" agent="techviz-harness" version="24.7.17" type="device">
+  <diagram id="session-sharing-path" name="세션 공유가 실제로 지나는 경로">
+    <mxGraphModel dx="680" dy="364" grid="1" gridSize="10" guides="1" tooltips="1" connect="1" arrows="1" fold="1" page="1" pageScale="1" pageWidth="827" pageHeight="1169" math="0" shadow="0">
+      <root>
+        <mxCell id="0"/>
+        <mxCell id="1" parent="0"/>
+        <mxCell id="n_keycloak-0" value="keycloak-0&lt;br/&gt;자기가 처리한 로그인만 캐시" tooltip="로그인을 처리하고 자기 sessions 캐시에만 엔트리를 남긴다. | Evidence: L49-L51" style="whiteSpace=wrap;html=1;rounded=1;strokeWidth=2;fontSize=14;fontStyle=1;fillColor=#ffffff;strokeColor=#2d4357;verticalAlign=middle;strokeColor=#2563eb;strokeWidth=2;" vertex="1" parent="1">
+          <mxGeometry x="92.5" y="82.5" width="150.0" height="71.0" as="geometry"/>
+        </mxCell>
+        <mxCell id="n_keycloak-1" value="keycloak-1&lt;br/&gt;refresh 요청을 받으면 DB 를 조회" tooltip="다른 노드가 만든 세션을 캐시로 받지 않고 데이터베이스에서 읽는다. | Evidence: L48-L51" style="whiteSpace=wrap;html=1;rounded=1;strokeWidth=2;fontSize=14;fontStyle=1;fillColor=#ffffff;strokeColor=#2d4357;verticalAlign=middle;strokeColor=#2563eb;strokeWidth=2;" vertex="1" parent="1">
+          <mxGeometry x="70.0" y="225.5" width="195.0" height="71.0" as="geometry"/>
+        </mxCell>
+        <mxCell id="n_jgroups-ping" value="JGROUPS_PING" tooltip="노드가 서로를 발견하는 자리. 여기 등록되어 있다는 것과 세션이 복제된다는 것은 다른 사건이다. | Evidence: L44-L46" style="whiteSpace=wrap;html=1;rounded=1;strokeWidth=2;fontSize=14;fontStyle=1;fillColor=#ffffff;strokeColor=#2d4357;verticalAlign=middle;shape=cylinder3;boundedLbl=1;backgroundOutline=1;fillColor=#eef6fb;strokeColor=#9ca3af;fillColor=#f9fafb;" vertex="1" parent="1">
+          <mxGeometry x="454.5" y="60.0" width="150.0" height="90.0" as="geometry"/>
+        </mxCell>
+        <mxCell id="n_postgres" value="PostgreSQL&lt;br/&gt;offline_flag=&#x27;0&#x27; 이 온라인 세션" tooltip="OFFLINE_USER_SESSION 에 세션 행을 보관한다. 두 노드가 같은 행을 본다. | Evidence: L48-L52" style="whiteSpace=wrap;html=1;rounded=1;strokeWidth=2;fontSize=14;fontStyle=1;fillColor=#ffffff;strokeColor=#2d4357;verticalAlign=middle;shape=cylinder3;boundedLbl=1;backgroundOutline=1;fillColor=#eef6fb;strokeColor=#2563eb;strokeWidth=2;" vertex="1" parent="1">
+          <mxGeometry x="425.0" y="222.0" width="209.0" height="97.0" as="geometry"/>
+        </mxCell>
+        <mxCell id="e_k0-discovery" value="멤버 등록" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeWidth=2;endArrow=block;endFill=1;" edge="1" parent="1" source="n_keycloak-0" target="n_jgroups-ping">
+          <mxGeometry relative="1" as="geometry">
+            <mxPoint x="372.5" y="102.5" as="offset"/>
+          </mxGeometry>
+        </mxCell>
+        <mxCell id="e_k0-writes" value="세션 INSERT" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeWidth=2;endArrow=block;endFill=1;" edge="1" parent="1" source="n_keycloak-0" target="n_postgres">
+          <mxGeometry relative="1" as="geometry">
+            <mxPoint x="357.8" y="194.2" as="offset"/>
+          </mxGeometry>
+        </mxCell>
+        <mxCell id="e_k1-discovery" value="멤버 등록" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeWidth=2;endArrow=block;endFill=1;" edge="1" parent="1" source="n_keycloak-1" target="n_jgroups-ping">
+          <mxGeometry relative="1" as="geometry">
+            <mxPoint x="383.8" y="183.0" as="offset"/>
+          </mxGeometry>
+        </mxCell>
+        <mxCell id="e_k1-reads" value="세션 SELECT" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeWidth=2;endArrow=block;endFill=1;" edge="1" parent="1" source="n_keycloak-1" target="n_postgres">
+          <mxGeometry relative="1" as="geometry">
+            <mxPoint x="369.0" y="274.8" as="offset"/>
+          </mxGeometry>
+        </mxCell>
+      </root>
+    </mxGraphModel>
+  </diagram>
+</mxfile>
@@ -0,0 +1,685 @@
+{
+  "type": "excalidraw",
+  "version": 2,
+  "source": "techviz-harness",
+  "elements": [
+    {
+      "id": "edge-k0-discovery",
+      "type": "arrow",
+      "x": 242.5,
+      "y": 96.0,
+      "width": 212.0,
+      "height": 13.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": null,
+      "seed": 584024925,
+      "version": 1,
+      "versionNonce": 1230381351,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "points": [
+        [
+          0.0,
+          13.0
+        ],
+        [
+          106.0,
+          13.0
+        ],
+        [
+          106.0,
+          0.0
+        ],
+        [
+          212.0,
+          0.0
+        ]
+      ],
+      "lastCommittedPoint": null,
+      "startBinding": {
+        "elementId": "node-keycloak-0",
+        "focus": 0,
+        "gap": 4
+      },
+      "endBinding": {
+        "elementId": "node-jgroups-ping",
+        "focus": 0,
+        "gap": 4
+      },
+      "startArrowhead": null,
+      "endArrowhead": "arrow",
+      "elbowed": true
+    },
+    {
+      "id": "edge-label-k0-discovery",
+      "type": "text",
+      "x": 327.5,
+      "y": 90.5,
+      "width": 90,
+      "height": 24,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 239076698,
+      "version": 1,
+      "versionNonce": 442745641,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 13,
+      "fontFamily": 5,
+      "text": "멤버 등록",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "멤버 등록",
+      "autoResize": true,
+      "lineHeight": 1.25
+    },
+    {
+      "id": "edge-k0-writes",
+      "type": "arrow",
+      "x": 242.5,
+      "y": 127.0,
+      "width": 182.5,
+      "height": 134.5,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": null,
+      "seed": 567703682,
+      "version": 1,
+      "versionNonce": 1423801697,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "points": [
+        [
+          0.0,
+          0.0
+        ],
+        [
+          91.25,
+          0.0
+        ],
+        [
+          91.25,
+          134.5
+        ],
+        [
+          182.5,
+          134.5
+        ]
+      ],
+      "lastCommittedPoint": null,
+      "startBinding": {
+        "elementId": "node-keycloak-0",
+        "focus": 0,
+        "gap": 4
+      },
+      "endBinding": {
+        "elementId": "node-postgres",
+        "focus": 0,
+        "gap": 4
+      },
+      "startArrowhead": null,
+      "endArrowhead": "arrow",
+      "elbowed": true
+    },
+    {
+      "id": "edge-label-k0-writes",
+      "type": "text",
+      "x": 312.75,
+      "y": 182.25,
+      "width": 90,
+      "height": 24,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 1833086279,
+      "version": 1,
+      "versionNonce": 1211439496,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 13,
+      "fontFamily": 5,
+      "text": "세션 INSERT",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "세션 INSERT",
+      "autoResize": true,
+      "lineHeight": 1.25
+    },
+    {
+      "id": "edge-k1-discovery",
+      "type": "arrow",
+      "x": 265.0,
+      "y": 114.0,
+      "width": 189.5,
+      "height": 138.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": null,
+      "seed": 249138565,
+      "version": 1,
+      "versionNonce": 1103409032,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "points": [
+        [
+          0.0,
+          138.0
+        ],
+        [
+          94.75,
+          138.0
+        ],
+        [
+          94.75,
+          0.0
+        ],
+        [
+          189.5,
+          0.0
+        ]
+      ],
+      "lastCommittedPoint": null,
+      "startBinding": {
+        "elementId": "node-keycloak-1",
+        "focus": 0,
+        "gap": 4
+      },
+      "endBinding": {
+        "elementId": "node-jgroups-ping",
+        "focus": 0,
+        "gap": 4
+      },
+      "startArrowhead": null,
+      "endArrowhead": "arrow",
+      "elbowed": true
+    },
+    {
+      "id": "edge-label-k1-discovery",
+      "type": "text",
+      "x": 338.75,
+      "y": 171.0,
+      "width": 90,
+      "height": 24,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 693543637,
+      "version": 1,
+      "versionNonce": 134865854,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 13,
+      "fontFamily": 5,
+      "text": "멤버 등록",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "멤버 등록",
+      "autoResize": true,
+      "lineHeight": 1.25
+    },
+    {
+      "id": "edge-k1-reads",
+      "type": "arrow",
+      "x": 265.0,
+      "y": 270.0,
+      "width": 160.0,
+      "height": 9.5,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": null,
+      "seed": 1249142507,
+      "version": 1,
+      "versionNonce": 1362277348,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "points": [
+        [
+          0.0,
+          0.0
+        ],
+        [
+          80.0,
+          0.0
+        ],
+        [
+          80.0,
+          9.5
+        ],
+        [
+          160.0,
+          9.5
+        ]
+      ],
+      "lastCommittedPoint": null,
+      "startBinding": {
+        "elementId": "node-keycloak-1",
+        "focus": 0,
+        "gap": 4
+      },
+      "endBinding": {
+        "elementId": "node-postgres",
+        "focus": 0,
+        "gap": 4
+      },
+      "startArrowhead": null,
+      "endArrowhead": "arrow",
+      "elbowed": true
+    },
+    {
+      "id": "edge-label-k1-reads",
+      "type": "text",
+      "x": 324.0,
+      "y": 262.75,
+      "width": 90,
+      "height": 24,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 1330903131,
+      "version": 1,
+      "versionNonce": 222775751,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 13,
+      "fontFamily": 5,
+      "text": "세션 SELECT",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "세션 SELECT",
+      "autoResize": true,
+      "lineHeight": 1.25
+    },
+    {
+      "id": "node-keycloak-0",
+      "type": "rectangle",
+      "x": 92.5,
+      "y": 82.5,
+      "width": 150.0,
+      "height": 71.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "#ffffff",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 969396610,
+      "version": 1,
+      "versionNonce": 1478355734,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false
+    },
+    {
+      "id": "node-label-keycloak-0",
+      "type": "text",
+      "x": 102.5,
+      "y": 92.5,
+      "width": 130.0,
+      "height": 51.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 293436436,
+      "version": 1,
+      "versionNonce": 1829861746,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 15,
+      "fontFamily": 5,
+      "text": "keycloak-0\n자기가 처리한 로그인만 캐시",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "keycloak-0\n자기가 처리한 로그인만 캐시",
+      "autoResize": true,
+      "lineHeight": 1.25
+    },
+    {
+      "id": "node-keycloak-1",
+      "type": "rectangle",
+      "x": 70.0,
+      "y": 225.5,
+      "width": 195.0,
+      "height": 71.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "#ffffff",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 1492679290,
+      "version": 1,
+      "versionNonce": 684109252,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false
+    },
+    {
+      "id": "node-label-keycloak-1",
+      "type": "text",
+      "x": 80.0,
+      "y": 235.5,
+      "width": 175.0,
+      "height": 51.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 186685213,
+      "version": 1,
+      "versionNonce": 935977296,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 15,
+      "fontFamily": 5,
+      "text": "keycloak-1\nrefresh 요청을 받으면 DB 를 조회",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "keycloak-1\nrefresh 요청을 받으면 DB 를 조회",
+      "autoResize": true,
+      "lineHeight": 1.25
+    },
+    {
+      "id": "node-jgroups-ping",
+      "type": "rectangle",
+      "x": 454.5,
+      "y": 60.0,
+      "width": 150.0,
+      "height": 90.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "#e7f5ff",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 1691553665,
+      "version": 1,
+      "versionNonce": 657056607,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false
+    },
+    {
+      "id": "node-label-jgroups-ping",
+      "type": "text",
+      "x": 464.5,
+      "y": 70.0,
+      "width": 130.0,
+      "height": 70.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 593986141,
+      "version": 1,
+      "versionNonce": 116663944,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 15,
+      "fontFamily": 5,
+      "text": "JGROUPS_PING",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "JGROUPS_PING",
+      "autoResize": true,
+      "lineHeight": 1.25
+    },
+    {
+      "id": "node-postgres",
+      "type": "rectangle",
+      "x": 425.0,
+      "y": 222.0,
+      "width": 209.0,
+      "height": 97.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "#e7f5ff",
+      "fillStyle": "solid",
+      "strokeWidth": 2,
+      "strokeStyle": "solid",
+      "roughness": 1,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 1035759464,
+      "version": 1,
+      "versionNonce": 1511157596,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false
+    },
+    {
+      "id": "node-label-postgres",
+      "type": "text",
+      "x": 435.0,
+      "y": 232.0,
+      "width": 189.0,
+      "height": 77.0,
+      "angle": 0,
+      "strokeColor": "#1e1e1e",
+      "backgroundColor": "transparent",
+      "fillStyle": "solid",
+      "strokeWidth": 1,
+      "strokeStyle": "solid",
+      "roughness": 0,
+      "opacity": 100,
+      "groupIds": [],
+      "frameId": null,
+      "index": null,
+      "roundness": {
+        "type": 3
+      },
+      "seed": 1404040862,
+      "version": 1,
+      "versionNonce": 1598470501,
+      "isDeleted": false,
+      "boundElements": [],
+      "updated": 0,
+      "link": null,
+      "locked": false,
+      "fontSize": 15,
+      "fontFamily": 5,
+      "text": "PostgreSQL\noffline_flag='0' 이 온라인 세션",
+      "textAlign": "center",
+      "verticalAlign": "middle",
+      "containerId": null,
+      "originalText": "PostgreSQL\noffline_flag='0' 이 온라인 세션",
+      "autoResize": true,
+      "lineHeight": 1.25
+    }
+  ],
+  "appState": {
+    "gridSize": 10,
+    "viewBackgroundColor": "#ffffff",
+    "currentItemFontFamily": 5
+  },
+  "files": {}
+}
@@ -0,0 +1,32 @@
+{
+  "harness_version": "0.2.0",
+  "spec_id": "session-sharing-path",
+  "spec_version": "1.1",
+  "spec_sha256": "622b6917edfc97cfbbbeea476bac0bceab339d4734549895d8acd721284f0a42",
+  "source_context": {
+    "document": "docs/keycloak-session-store/final/document.md",
+    "document_sha256": "609353e10bfd37a9bbb6a79ecf2a32f3d3c02d5d161879a14ad4713e49e7e5e8",
+    "anchor": {
+      "kind": "heading",
+      "value": "그런데 첫 실험에서 전제가 무너졌다",
+      "line": 33
+    }
+  },
+  "outputs": [
+    "session-sharing-path.svg",
+    "session-sharing-path.mmd",
+    "session-sharing-path.d2",
+    "session-sharing-path.dot",
+    "session-sharing-path.drawio",
+    "session-sharing-path.excalidraw",
+    "session-sharing-path.alt.md"
+  ],
+  "lint_issue_count": 1,
+  "assumption_count": 0,
+  "assumptions_allowed": false,
+  "composition_profile": "component-flow",
+  "reference_ids": [
+    "payment-event-flow"
+  ],
+  "diagram_only": true
+}
@@ -0,0 +1,11 @@
+%% 세션 공유가 실제로 지나는 경로
+%% question: 두 Keycloak 노드가 같은 세션을 아는 것은 무엇 때문인가
+flowchart LR
+    n0["keycloak-0"]
+    n1[("PostgreSQL")]
+    n2["keycloak-1"]
+    n3[("JGROUPS_PING")]
+    n0 -->|"세션 INSERT"| n1
+    n2 -->|"세션 SELECT"| n1
+    n0 -->|"멤버 등록"| n3
+    n2 -->|"멤버 등록"| n3
@@ -0,0 +1,87 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" width="680" height="364" viewBox="0 0 680 364" role="img" aria-labelledby="diagram-title diagram-description">
+<title id="diagram-title">세션 공유가 실제로 지나는 경로</title>
+<desc id="diagram-description">keycloak-0 과 keycloak-1 은 JGROUPS_PING 테이블을 통해 서로를 발견하고 클러스터 뷰를 형성한다. 그러나 sessions 캐시의 엔트리는 노드 사이로 복제되지 않으며, 각 노드는 자기가 처리한 로그인만 캐시한다. 노드 A 로 로그인한 세션을 노드 B 가 아는 이유는 노드 B 가 PostgreSQL 의 OFFLINE_USER_SESSION 을 직접 읽기 때문이고, 이는 반대편 노드가 날린 SQL 을 문장 로깅으로 잡아 확인했다.</desc>
+<metadata>{&quot;techviz&quot;:{&quot;spec_version&quot;:&quot;1.1&quot;,&quot;id&quot;:&quot;session-sharing-path&quot;,&quot;profile&quot;:&quot;component-flow&quot;},&quot;source_context&quot;:{&quot;document&quot;:&quot;docs/keycloak-session-store/final/document.md&quot;,&quot;document_sha256&quot;:&quot;609353e10bfd37a9bbb6a79ecf2a32f3d3c02d5d161879a14ad4713e49e7e5e8&quot;,&quot;anchor&quot;:{&quot;kind&quot;:&quot;heading&quot;,&quot;value&quot;:&quot;그런데 첫 실험에서 전제가 무너졌다&quot;,&quot;line&quot;:33}},&quot;evidence_policy&quot;:&quot;Each factual element cites source lines or is marked assumption.&quot;,&quot;diagram_only&quot;:true}</metadata>
+<defs>
+  <marker id="arrow" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
+    <path d="M 0 0 L 10 5 L 0 10 z" />
+  </marker>
+  <style>
+    :root { color-scheme: light; }
+    text { font-family: Inter, Pretendard, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; fill: #111827; }
+    .canvas { fill: #ffffff; }
+    .group-box { fill: #ffffff; stroke: #9ca3af; stroke-width: 1.4; stroke-dasharray: 7 5; }
+    .group-label-bg { fill: #ffffff; }
+    .group-label { font-size: 13px; font-weight: 650; fill: #374151; }
+    .edge { fill: none; stroke: #374151; stroke-width: 1.8; stroke-linejoin: round; stroke-linecap: round; marker-end: url(#arrow); }
+    .edge.style-dashed, .edge.semantic-dashed, .edge.assumption { stroke-dasharray: 7 5; }
+    .edge.style-dotted { stroke-dasharray: 2 5; }
+    .edge.emphasis-primary { stroke: #2563eb; stroke-width: 2.2; }
+    .edge.emphasis-muted { stroke: #9ca3af; }
+    .edge.emphasis-warning, .edge.kind-failure, .edge.kind-error { stroke: #dc2626; stroke-width: 2.2; }
+    .edge-label-bg { fill: #ffffff; }
+    .edge-label { font-size: 12px; font-weight: 560; text-anchor: middle; }
+    .node-shape { fill: #ffffff; stroke: #4b5563; stroke-width: 1.7; }
+    .node-shape.emphasis-primary { stroke: #2563eb; stroke-width: 2.2; }
+    .node-shape.emphasis-muted { stroke: #9ca3af; fill: #f9fafb; }
+    .node-shape.emphasis-warning { stroke: #d97706; stroke-width: 2; fill: #fffdf5; }
+    .node-shape.kind-database, .node-shape.kind-datastore, .node-shape.kind-storage { fill: #f8fafc; }
+    .node-shape.kind-queue, .node-shape.kind-event, .node-shape.kind-topic { fill: #fafafa; }
+    .node-shape.assumption { stroke-dasharray: 4 4; }
+    .storage-bottom, .controller-divider { fill: none; stroke: #4b5563; stroke-width: 1.4; }
+    .controller-led { fill: #4b5563; }
+    .actor-symbol { fill: none; stroke: #4b5563; stroke-width: 1.8; stroke-linecap: round; }
+    .actor-symbol.emphasis-primary { stroke: #2563eb; stroke-width: 2.2; }
+    .node-label { font-size: 14px; font-weight: 650; text-anchor: middle; }
+    .node-role { font-size: 10px; letter-spacing: 0.04em; text-anchor: middle; fill: #6b7280; }
+    .node-detail-divider { stroke: #d1d5db; stroke-width: 1; }
+    .node-detail { font-size: 11px; fill: #374151; }
+    .assumption-badge { font-size: 9px; font-weight: 700; fill: #92400e; }
+    .failure-mark { stroke: #dc2626; stroke-width: 4; stroke-linecap: round; }
+    .lifeline { stroke: #9ca3af; stroke-width: 1.2; stroke-dasharray: 5 5; }
+    .timeline-axis { stroke: #374151; stroke-width: 1.8; marker-end: url(#arrow); }
+    .timeline-stem { stroke: #6b7280; stroke-width: 1.3; }
+    .timeline-marker { fill: #ffffff; stroke: #374151; stroke-width: 1.7; }
+    .timeline-marker.primary { fill: #2563eb; stroke: #2563eb; }
+    .timeline-marker.warning { fill: #dc2626; stroke: #dc2626; }
+    .timeline-label { font-size: 13px; font-weight: 650; text-anchor: middle; }
+    .timeline-detail { font-size: 11px; fill: #4b5563; text-anchor: middle; }
+  </style>
+</defs>
+<rect class="canvas" width="680" height="364" />
+<polyline class="edge kind-write style-solid emphasis-normal" points="242.5,109.0 348.5,109.0 348.5,96.0 454.5,96.0" data-evidence="44-45" />
+<rect class="edge-label-bg" x="346.8" y="88.5" width="51.5" height="22" rx="3" />
+<text class="edge-label" x="372.5" y="103.5">멤버 등록</text>
+<polyline class="edge kind-write style-solid emphasis-normal" points="242.5,127.0 333.8,127.0 333.8,261.5 425.0,261.5" data-evidence="49-52" />
+<rect class="edge-label-bg" x="318.6" y="180.2" width="78.3" height="22" rx="3" />
+<text class="edge-label" x="357.8" y="195.2">세션 INSERT</text>
+<polyline class="edge kind-write style-solid emphasis-normal" points="265.0,252.0 359.8,252.0 359.8,114.0 454.5,114.0" data-evidence="44-45" />
+<rect class="edge-label-bg" x="358.0" y="169.0" width="51.5" height="22" rx="3" />
+<text class="edge-label" x="383.8" y="184.0">멤버 등록</text>
+<polyline class="edge kind-read style-solid emphasis-normal" points="265.0,270.0 345.0,270.0 345.0,279.5 425.0,279.5" data-evidence="48-50" />
+<rect class="edge-label-bg" x="329.9" y="260.8" width="78.3" height="22" rx="3" />
+<text class="edge-label" x="369.0" y="275.8">세션 SELECT</text>
+<g id="node-keycloak-0">
+<rect class="node-shape kind-service emphasis-primary role-source" data-evidence="49-51" x="92.5" y="82.5" width="150.0" height="71.0" rx="7" />
+<text class="node-label" x="167.5" y="109.5">keycloak-0</text>
+<line class="node-detail-divider" x1="106.5" y1="130.5" x2="228.5" y2="130.5" />
+<text class="node-detail" x="108.5" y="147.5">자기가 처리한 로그인만 캐시</text>
+</g>
+<g id="node-keycloak-1">
+<rect class="node-shape kind-service emphasis-primary role-target" data-evidence="48-51" x="70.0" y="225.5" width="195.0" height="71.0" rx="7" />
+<text class="node-label" x="167.5" y="252.5">keycloak-1</text>
+<line class="node-detail-divider" x1="84.0" y1="273.5" x2="251.0" y2="273.5" />
+<text class="node-detail" x="86.0" y="290.5">refresh 요청을 받으면 DB 를 조회</text>
+</g>
+<g id="node-jgroups-ping">
+<rect class="node-shape kind-datastore emphasis-muted role-support" data-evidence="44-46" x="454.5" y="73.0" width="150.0" height="64.0" /><ellipse class="node-shape kind-datastore emphasis-muted role-support" cx="529.5" cy="73.0" rx="75.0" ry="13.0" /><path class="storage-bottom" d="M 454.5 137.0 A 75.0 13.0 0 0 0 604.5 137.0" />
+<text class="node-label" x="529.5" y="103.0">JGROUPS_PING</text>
+</g>
+<g id="node-postgres">
+<rect class="node-shape kind-datastore emphasis-primary role-store" data-evidence="48-52" x="425.0" y="235.0" width="209.0" height="71.0" /><ellipse class="node-shape kind-datastore emphasis-primary role-store" cx="529.5" cy="235.0" rx="104.5" ry="13.0" /><path class="storage-bottom" d="M 425.0 306.0 A 104.5 13.0 0 0 0 634.0 306.0" />
+<text class="node-label" x="529.5" y="262.0">PostgreSQL</text>
+<line class="node-detail-divider" x1="439.0" y1="283.0" x2="620.0" y2="283.0" />
+<text class="node-detail" x="441.0" y="300.0">offline_flag=&#x27;0&#x27; 이 온라인 세션</text>
+</g>
+</svg>