feat(server-s3): a member's tmux follows tmux upgrades — tmux-member + Users → Members' tmux

A member's tmux server keeps the version it started with until their last
pane closes, but the dashboard asked it with TMUX_BIN, the newest tmux: a
3.8 client on a 3.6 server spun it at 100% CPU (three members needed a
manual kill on 2026-10-15).

- /opt/agenthub/libexec/tmux-member (install-system, in sudoers): runs a
  member's tmux call with the binary of THEIR running server
  (/proc/<pid>/exe, found from the socket in /proc/net/unix), else
  TMUX_BIN. It runs as the member and execs only a process they own.
  sudoArgv uses it once installed (linux-accounts readConf), TMUX_BIN
  until then.
- Users → Members' tmux (GET /api/users/tmux): each member server's version
  beside the installed one, sessions, agents working. An admin restarts one
  (POST /api/users/:id/tmux-restart) or every idle outdated one
  (POST /api/users/tmux-restart-idle), with their password again, audited
  per member; a server that will not stop answers 409 ETMUXSTUCK naming
  its pid for root.
- server-s3-system.test.js: `delete` is a provision action since Delete
  user, so the "unknown action" case now uses `purge`.

Operators: run `sudo agenthub server install-system` once.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

client/src/components/users/MemberTmuxCard.tsx

@@ -0,0 +1,267 @@
+/**
+ * @file MemberTmuxCard.tsx
+ * @description The Users page's tmux card (one Linux user per account only,
+ * `GET /api/users/tmux`): each member's own tmux server — the version it runs
+ * beside the installed one, its sessions, whether an agent of theirs is
+ * working — so an admin sees who still runs an old tmux after an upgrade.
+ * An admin restarts one member's server, or every idle outdated one at once
+ * (`POST /api/users/:id/tmux-restart`, `/api/users/tmux-restart-idle`), each
+ * time with their own password again; a restart ends that member's panes,
+ * and the next start runs the installed tmux. An analyst only reads.
+ * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+ */
+
+import { useCallback, useEffect, useState, type ReactNode } from "react";
+import { useTranslation } from "react-i18next";
+import type { TFunction } from "i18next";
+import { RefreshCw, RotateCcw, TerminalSquare } from "lucide-react";
+import { api, type MemberTmux, type MemberTmuxRow } from "../../lib/api";
+import { formatDateTime } from "../../lib/format";
+import { toast } from "../../lib/toast";
+import { isSubmitEnter } from "../../lib/keys";
+import { useSpin } from "../../hooks/useSpin";
+import { ConfirmModal } from "../ConfirmModal";
+
+function errorText(t: TFunction<"users">, e: unknown): string {
+  const err = e as Error & { code?: string };
+  return err.code && t(`tmux.errors.${err.code}`, { defaultValue: "" })
+    ? t(`tmux.errors.${err.code}`)
+    : err.message;
+}
+
+const BADGE = "badge ml-1.5 py-0 text-[10px]";
+const WARN = `${BADGE} bg-status-warning/10 text-status-warning border-status-warning/20`;
+const DANGER = `${BADGE} bg-status-danger/10 text-status-danger border-status-danger/20`;
+
+export function MemberTmuxCard({ isAdmin }: { isAdmin: boolean }) {
+  const { t } = useTranslation("users");
+  const [data, setData] = useState<MemberTmux | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  // A member row = restart that one; "idle" = every idle outdated member.
+  const [restarting, setRestarting] = useState<MemberTmuxRow | "idle" | null>(null);
+
+  const load = useCallback(
+    () =>
+      api.users
+        .tmux()
+        .then((r) => {
+          setData(r);
+          setError(null);
+        })
+        .catch((e: Error) => setError(e.message)),
+    []
+  );
+  const [spinning, refresh] = useSpin(load);
+  useEffect(() => {
+    void load();
+  }, [load]);
+
+  if (!data?.available) return null;
+  const rows = data.users.filter((u) => u.running);
+  const idleOutdated = rows.filter((u) => u.outdated && u.busy === 0);
+  const th = "px-5 py-2.5 text-[11px] font-semibold text-fg-muted uppercase tracking-wider";
+
+  return (
+    <section className="card" data-testid="member-tmux">
+      <div className="flex flex-wrap items-center gap-2 px-5 py-4 border-b border-border">
+        <TerminalSquare className="w-4 h-4 text-fg-muted" />
+        <div className="flex-1 min-w-0">
+          <h2 className="text-sm font-semibold text-fg-primary">{t("tmux.title")}</h2>
+          <p className="text-xs text-fg-muted">
+            {t("tmux.description", { version: data.installed ?? "?" })}
+          </p>
+        </div>
+        <button
+          type="button"
+          onClick={refresh}
+          disabled={spinning}
+          aria-busy={spinning}
+          title={t("tmux.refresh")}
+          aria-label={t("tmux.refresh")}
+          className="btn-icon"
+        >
+          <RefreshCw className={`w-4 h-4 ${spinning ? "animate-spin" : ""}`} />
+        </button>
+        {isAdmin && idleOutdated.length > 0 && (
+          <button type="button" onClick={() => setRestarting("idle")} className="btn-primary">
+            <RotateCcw className="w-4 h-4" />{" "}
+            {t("tmux.restartIdle", { count: idleOutdated.length })}
+          </button>
+        )}
+      </div>
+      {!data.matched && (
+        <p className="px-5 py-2.5 text-xs text-status-warning border-b border-border">
+          {t("tmux.notMatched")}
+        </p>
+      )}
+      {error && (
+        <p role="alert" className="px-5 py-3 text-xs text-status-danger">
+          {error}
+        </p>
+      )}
+      {rows.length === 0 ? (
+        <p className="px-5 py-8 text-center text-sm text-fg-muted">{t("tmux.empty")}</p>
+      ) : (
+        <div className="overflow-x-auto">
+          <table className="w-full min-w-[560px]">
+            <thead>
+              <tr className="border-b border-border text-left">
+                <th className={th}>{t("tmux.user")}</th>
+                <th className={th}>{t("tmux.version")}</th>
+                <th className={`${th} text-right`}>{t("tmux.sessions")}</th>
+                <th className={th}>{t("tmux.agents")}</th>
+                {isAdmin && <th className={`${th} text-right`}>{t("actions")}</th>}
+              </tr>
+            </thead>
+            <tbody className="divide-y divide-border">
+              {rows.map((u) => (
+                <tr key={u.id}>
+                  <td className="px-5 py-2.5 text-sm text-fg-primary">{u.username}</td>
+                  <td className="px-5 py-2.5 text-sm text-fg-secondary">
+                    <span className="font-mono">{u.stuck ? "?" : (u.version ?? "?")}</span>
+                    {u.stuck && <span className={DANGER}>{t("tmux.stuck")}</span>}
+                    {u.outdated && <span className={WARN}>{t("tmux.outdated")}</span>}
+                    {u.startedAt && (
+                      <div className="text-[11px] text-fg-muted">
+                        {t("tmux.since", {
+                          at: formatDateTime(new Date(u.startedAt).toISOString()),
+                        })}
+                      </div>
+                    )}
+                  </td>
+                  <td className="px-5 py-2.5 text-right text-sm tabular-nums text-fg-secondary">
+                    {u.sessions ?? "—"}
+                  </td>
+                  <td className="px-5 py-2.5 text-sm text-fg-secondary">
+                    {u.busy > 0 ? t("tmux.working", { count: u.busy }) : t("tmux.idle")}
+                  </td>
+                  {isAdmin && (
+                    <td className="px-5 py-2 text-right">
+                      <button
+                        type="button"
+                        onClick={() => setRestarting(u)}
+                        title={t("tmux.restart", { name: u.username })}
+                        aria-label={t("tmux.restart", { name: u.username })}
+                        className="btn-icon"
+                      >
+                        <RotateCcw className="h-4 w-4" />
+                      </button>
+                    </td>
+                  )}
+                </tr>
+              ))}
+            </tbody>
+          </table>
+        </div>
+      )}
+      {restarting && (
+        <RestartDialog
+          target={restarting}
+          idle={idleOutdated}
+          onClose={() => setRestarting(null)}
+          onDone={(msg) => {
+            toast.success(msg);
+            setRestarting(null);
+            void load();
+          }}
+        />
+      )}
+    </section>
+  );
+}
+
+function RestartDialog({
+  target,
+  idle,
+  onClose,
+  onDone,
+}: {
+  target: MemberTmuxRow | "idle";
+  idle: MemberTmuxRow[];
+  onClose: () => void;
+  onDone: (message: string) => void;
+}) {
+  const { t } = useTranslation("users");
+  const [current, setCurrent] = useState("");
+  const [busy, setBusy] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+  const one = target === "idle" ? null : target;
+
+  const submit = async () => {
+    if (!current || busy) return;
+    setBusy(true);
+    setError(null);
+    try {
+      if (one) {
+        await api.users.tmuxRestart(one.id, current);
+        onDone(t("tmux.done", { name: one.username }));
+      } else {
+        const r = await api.users.tmuxRestartIdle(current);
+        // A server that would not stop needs root: say which, the rest went.
+        if (r.failed.length) toast.error(r.failed.map((f) => f.message).join("\n"));
+        onDone(t("tmux.doneIdle", { names: r.restarted.join(", ") || "—" }));
+      }
+    } catch (e) {
+      setError(errorText(t, e));
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  return (
+    <ConfirmModal
+      open
+      title={one ? t("tmux.restart", { name: one.username }) : t("tmux.restartIdleTitle")}
+      message={
+        one
+          ? t(one.busy > 0 ? "tmux.restartHintBusy" : "tmux.restartHint", {
+              name: one.username,
+              count: one.sessions ?? 0,
+            })
+          : t("tmux.restartIdleHint", { names: idle.map((u) => u.username).join(", ") })
+      }
+      confirmLabel={t("tmux.restartButton")}
+      cancelLabel={t("common:cancel")}
+      busy={busy}
+      disabled={!current}
+      onConfirm={() => void submit()}
+      onCancel={onClose}
+    >
+      <div
+        className="mt-3 space-y-3"
+        onKeyDown={(e) => {
+          if (isSubmitEnter(e)) {
+            e.preventDefault();
+            void submit();
+          }
+        }}
+      >
+        <Field label={t("yourPassword")} hint={t("yourPasswordHint")}>
+          <input
+            type="password"
+            className="input w-full text-sm"
+            value={current}
+            onChange={(e) => setCurrent(e.target.value)}
+            autoComplete="current-password"
+            aria-label={t("yourPassword")}
+          />
+        </Field>
+        {error && (
+          <p role="alert" className="whitespace-pre-line text-xs text-status-danger">
+            {error}
+          </p>
+        )}
+      </div>
+    </ConfirmModal>
+  );
+}
+
+function Field({ label, hint, children }: { label: string; hint?: string; children: ReactNode }) {
+  return (
+    <label className="block">
+      <span className="text-xs font-medium text-fg-secondary">{label}</span>
+      <div className="mt-1">{children}</div>
+      {hint && <span className="mt-0.5 block text-[11px] text-fg-muted">{hint}</span>}
+    </label>
+  );
+}

client/src/components/users/__tests__/MemberTmuxCard.test.tsx

@@ -0,0 +1,100 @@
+/**
+ * @file MemberTmuxCard.test.tsx
+ * @description The Users page's members' tmux card: hidden without one Linux
+ * user per account, lists each running member server with its version and a
+ * badge when it is older than the installed tmux, warns until tmux-member is
+ * installed, and an admin restarts one member — or every idle outdated one,
+ * the working member left out — only with their own password typed; an
+ * analyst sees no restart control.
+ * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+ */
+
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { render, screen, waitFor } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import type { MemberTmux } from "../../../lib/api";
+
+const users = vi.hoisted(() => ({
+  tmux: vi.fn(),
+  tmuxRestart: vi.fn(),
+  tmuxRestartIdle: vi.fn(),
+}));
+vi.mock("../../../lib/api", async (importOriginal) => {
+  const actual = await importOriginal<Record<string, unknown>>();
+  return { ...actual, api: { users } };
+});
+vi.mock("../../../lib/toast", () => ({ toast: { success: vi.fn(), error: vi.fn() } }));
+
+import { MemberTmuxCard } from "../MemberTmuxCard";
+
+const DATA: MemberTmux = {
+  available: true,
+  installed: "3.8",
+  matched: true,
+  users: [
+    { id: 2, username: "mia", running: true, version: "3.6", sessions: 2, busy: 0, outdated: true },
+    { id: 3, username: "zed", running: true, version: "3.6", sessions: 1, busy: 1, outdated: true },
+    {
+      id: 4,
+      username: "ann",
+      running: true,
+      version: "3.8",
+      sessions: 3,
+      busy: 0,
+      outdated: false,
+    },
+    { id: 5, username: "bob", running: false, busy: 0, outdated: false },
+  ],
+};
+
+beforeEach(() => {
+  vi.clearAllMocks();
+  users.tmux.mockResolvedValue(DATA);
+});
+
+describe("MemberTmuxCard", () => {
+  it("renders nothing without one Linux user per account", async () => {
+    users.tmux.mockResolvedValue({ available: false, users: [] });
+    const { container } = render(<MemberTmuxCard isAdmin />);
+    await waitFor(() => expect(users.tmux).toHaveBeenCalled());
+    expect(container).toBeEmptyDOMElement();
+  });
+
+  it("lists running servers and marks the ones older than the installed tmux", async () => {
+    render(<MemberTmuxCard isAdmin={false} />);
+    expect(await screen.findByText("mia")).toBeInTheDocument();
+    expect(screen.queryByText("bob")).toBeNull();
+    expect(screen.getAllByText("older than installed")).toHaveLength(2);
+    expect(screen.getByText(/Installed: tmux 3\.8/)).toBeInTheDocument();
+    // An analyst reads only.
+    expect(screen.queryByRole("button", { name: /Restart/ })).toBeNull();
+  });
+
+  it("warns until tmux-member is installed", async () => {
+    users.tmux.mockResolvedValue({ ...DATA, matched: false });
+    render(<MemberTmuxCard isAdmin />);
+    expect(await screen.findByText(/install-system/)).toBeInTheDocument();
+  });
+
+  it("restarts one member only with the admin's password", async () => {
+    users.tmuxRestart.mockResolvedValue({});
+    render(<MemberTmuxCard isAdmin />);
+    await userEvent.click(await screen.findByRole("button", { name: "Restart mia's tmux" }));
+    expect(screen.getByText(/Every pane of mia closes \(2 sessions\)/)).toBeInTheDocument();
+    const go = screen.getByRole("button", { name: "Restart" });
+    expect(go).toBeDisabled();
+    await userEvent.type(screen.getByLabelText("Your password"), "pw");
+    await userEvent.click(go);
+    await waitFor(() => expect(users.tmuxRestart).toHaveBeenCalledWith(2, "pw"));
+  });
+
+  it("restarts every idle outdated member at once, the working one left out", async () => {
+    users.tmuxRestartIdle.mockResolvedValue({ restarted: ["mia"], skipped: ["zed"], failed: [] });
+    render(<MemberTmuxCard isAdmin />);
+    await userEvent.click(await screen.findByRole("button", { name: "Restart 1 idle member" }));
+    expect(screen.getByText(/no agent working: mia\./)).toBeInTheDocument();
+    await userEvent.type(screen.getByLabelText("Your password"), "pw");
+    await userEvent.click(screen.getByRole("button", { name: "Restart" }));
+    await waitFor(() => expect(users.tmuxRestartIdle).toHaveBeenCalledWith("pw"));
+  });
+});

client/src/i18n/locales/en/users.json

@@ -204,5 +204,35 @@
     "body": "This deletes {{name}} for good: their login, {{count}} workspace(s), and their Linux account with the whole home folder (/srv/agenthub/users/{{user}}) — every file and all source code in it. It cannot be undone. Session history and the audit log stay.",
     "confirm": "Delete for good",
     "needsPassword": "Enter your own password below first."
+  },
+  "tmux": {
+    "title": "Members' tmux",
+    "description": "Each member's own tmux server keeps the version it started with until its last pane closes. Installed: tmux {{version}}.",
+    "refresh": "Refresh",
+    "notMatched": "Run `sudo agenthub server install-system` once: until then an older member server is asked with the installed tmux, which can leave it stuck at 100% CPU.",
+    "empty": "No member has a tmux server running.",
+    "user": "User",
+    "version": "tmux",
+    "sessions": "Sessions",
+    "agents": "Agents",
+    "stuck": "not answering",
+    "outdated": "older than installed",
+    "since": "since {{at}}",
+    "working_one": "{{count}} working",
+    "working_other": "{{count}} working",
+    "idle": "idle",
+    "restart": "Restart {{name}}'s tmux",
+    "restartIdle_one": "Restart {{count}} idle member",
+    "restartIdle_other": "Restart {{count}} idle members",
+    "restartIdleTitle": "Restart idle members' tmux",
+    "restartHint": "Every pane of {{name}} closes ({{count}} sessions). Their Claude sessions resume from the workspace, and the next start runs the installed tmux.",
+    "restartHintBusy": "An agent of {{name}} is working right now and will be stopped. Every pane of theirs closes ({{count}} sessions); their Claude sessions resume from the workspace.",
+    "restartIdleHint": "Restarts the tmux of every member on an older version with no agent working: {{names}}. Their panes close; their Claude sessions resume from the workspace.",
+    "restartButton": "Restart",
+    "done": "{{name}}'s tmux restarted",
+    "doneIdle": "Restarted: {{names}}",
+    "errors": {
+      "ETMUXSTUCK": "The server did not stop. Run the `sudo kill -9` command shown, as root, on the server."
+    }
   }
 }

client/src/i18n/locales/vi/users.json

@@ -204,5 +204,35 @@
     "body": "Thao tác này xoá vĩnh viễn {{name}}: tài khoản đăng nhập, {{count}} workspace, và tài khoản Linux cùng toàn bộ thư mục home (/srv/agenthub/users/{{user}}) — mọi file và source code trong đó. Không thể khôi phục. Lịch sử session và audit log vẫn được giữ.",
     "confirm": "Xoá vĩnh viễn",
     "needsPassword": "Hãy nhập mật khẩu của bạn ở ô bên dưới trước."
+  },
+  "tmux": {
+    "title": "Tmux của member",
+    "description": "Mỗi member có tmux server riêng, giữ phiên bản lúc nó khởi động cho đến khi pane cuối cùng đóng. Bản đã cài: tmux {{version}}.",
+    "refresh": "Làm mới",
+    "notMatched": "Chạy `sudo agenthub server install-system` một lần: trước đó, server cũ của member được hỏi bằng tmux bản mới và có thể kẹt ở 100% CPU.",
+    "empty": "Không member nào đang chạy tmux server.",
+    "user": "Người dùng",
+    "version": "tmux",
+    "sessions": "Session",
+    "agents": "Agent",
+    "stuck": "không trả lời",
+    "outdated": "cũ hơn bản cài",
+    "since": "từ {{at}}",
+    "working_one": "{{count}} đang chạy",
+    "working_other": "{{count}} đang chạy",
+    "idle": "rảnh",
+    "restart": "Khởi động lại tmux của {{name}}",
+    "restartIdle_one": "Khởi động lại {{count}} member đang rảnh",
+    "restartIdle_other": "Khởi động lại {{count}} member đang rảnh",
+    "restartIdleTitle": "Khởi động lại tmux của member đang rảnh",
+    "restartHint": "Mọi pane của {{name}} sẽ đóng ({{count}} session). Phiên Claude của họ resume lại được từ workspace, và lần Start sau sẽ chạy tmux bản đã cài.",
+    "restartHintBusy": "Agent của {{name}} đang chạy và sẽ bị dừng. Mọi pane của họ sẽ đóng ({{count}} session); phiên Claude resume lại được từ workspace.",
+    "restartIdleHint": "Khởi động lại tmux của mọi member đang chạy bản cũ mà không có agent nào đang chạy: {{names}}. Pane của họ sẽ đóng; phiên Claude resume lại được từ workspace.",
+    "restartButton": "Khởi động lại",
+    "done": "Đã khởi động lại tmux của {{name}}",
+    "doneIdle": "Đã khởi động lại: {{names}}",
+    "errors": {
+      "ETMUXSTUCK": "Server không dừng. Chạy lệnh `sudo kill -9` được nêu, bằng quyền root, trên máy server."
+    }
   }
 }

client/src/lib/api.ts

@@ -544,6 +544,31 @@ export type ServerUserUsage = AuthUser & {
   logins?: number;
   lastLoginAt?: string | null;
 };
+/** One member's own tmux server (`GET /api/users/tmux`). */
+export interface MemberTmuxRow {
+  id: number;
+  username: string;
+  running: boolean;
+  /** Did not answer (hung, or backed off). */
+  stuck?: boolean;
+  version?: string | null;
+  pid?: number | null;
+  startedAt?: number | null;
+  sessions?: number | null;
+  /** Workspaces of theirs with an agent working now. */
+  busy: number;
+  /** Runs an older tmux than the installed one. */
+  outdated: boolean;
+}
+/** `GET /api/users/tmux`: `available` only with one Linux user per account. */
+export interface MemberTmux {
+  available: boolean;
+  installed?: string | null;
+  /** Calls on an older server already use its own binary (tmux-member installed). */
+  matched?: boolean;
+  users: MemberTmuxRow[];
+}
+
 /** One user's home folder on disk (`GET /api/users/storage`); null = not measured. */
 export type UserStorage = {
   bytes: number;
@@ -915,6 +940,24 @@ export const api = {
         method: "POST",
         body: JSON.stringify({ ...body, currentPassword }),
       }),
+    /** GET /api/users/tmux — each member's own tmux server beside the installed version (S3). */
+    tmux: () => request<MemberTmux>("/users/tmux"),
+    /** POST /api/users/:id/tmux-restart — end that member's tmux server (every pane of theirs). */
+    tmuxRestart: (id: number, currentPassword: string) =>
+      request<{ user: AuthUser }>(`/users/${id}/tmux-restart`, {
+        method: "POST",
+        body: JSON.stringify({ currentPassword }),
+      }),
+    /** POST /api/users/tmux-restart-idle — restart every outdated member server with no agent working. */
+    tmuxRestartIdle: (currentPassword: string) =>
+      request<{
+        restarted: string[];
+        skipped: string[];
+        failed: { username: string; message: string }[];
+      }>("/users/tmux-restart-idle", {
+        method: "POST",
+        body: JSON.stringify({ currentPassword }),
+      }),
     /** GET /api/users/:id — one account and the workspaces it owns (admin/analyst). */
     get: (id: number) => request<UserDetail>(`/users/${id}`),
     /** PATCH /api/users/:id — profile, role, state, password, workspaces and

client/src/pages/Users.tsx

@@ -9,7 +9,9 @@
  * an admin — add a user, and ONE Edit per row (`UserEditDialog`: profile,
  * role, active/disabled, password, owned workspaces, sign out everywhere, sent
  * as one change), and the Claude/Codex account pool every user's sessions run
- * on (`AccountPoolCard`). Every change asks for the admin's OWN password again (the
+ * on (`AccountPoolCard`), and (one Linux user per account) each member's own
+ * tmux server beside the installed version, restartable by an admin
+ * (`MemberTmuxCard`). Every change asks for the admin's OWN password again (the
  * server refuses without it); an analyst only reads. A row shows the display
  * name and email under the username when set.
  * Laid out like the other list pages: icon header, a row of totals
@@ -48,6 +50,7 @@ import { ConfirmModal } from "../components/ConfirmModal";
 import { StatCard } from "../components/StatCard";
 import { ROLE_BADGE, UserEditDialog } from "../components/users/UserEditDialog";
 import { AccountPoolCard } from "../components/users/AccountPoolCard";
+import { MemberTmuxCard } from "../components/users/MemberTmuxCard";
 import { TableRowSkeleton } from "../components/Skeleton";
 
 type Role = AuthUser["role"];
@@ -296,6 +299,7 @@ export function Users() {
       </div>
 
       <AccountPoolCard isAdmin={isAdmin} />
+      <MemberTmuxCard isAdmin={isAdmin} />
 
       <section className="card">
         <div className="flex items-center gap-2 px-5 py-4 border-b border-border">

client/src/pages/__tests__/Users.test.tsx

@@ -40,6 +40,8 @@ const users = vi.hoisted(() => ({
   setPassword: vi.fn(),
   assignWorkspace: vi.fn(),
   get: vi.fn(),
+  // No S3 here: the members' tmux card stays hidden.
+  tmux: vi.fn(async () => ({ available: false, users: [] })),
 }));
 
 vi.mock("../../lib/api", async (importOriginal) => {

docs/API.md

@@ -85,7 +85,7 @@ A dashboard shared by several people runs in **server mode** ([SERVER-MODE.md](S
 | `POST /api/auth/login` `{username, password}` | `{user}` + the cookie; `401 EBADLOGIN`, `429 ETOOMANY`, `404 ENOTSERVER` in local mode |
 | `POST /api/auth/logout` | `{ok: true}`, cookie cleared |
 
-In server mode a **developer** sees only rows of the workspaces they own (`lanes.owner_id`): every list, count, chart and cost answer is limited to them, and a request naming another user's session, agent, workspace or run (in the path, query or body) answers `404 ENOTFOUND`. Admin and analyst see everything; `GET /api/users` lists every account (`displayName`, `email`, `createdAt`, `logins`, `lastLoginAt` included) with its workspaces, sessions and 7/30-day `{cost, tokens}`, `GET /api/users/storage[?refresh=1]` each user's home size (`{storage: {<id>: {bytes, files, partial, measuredAt} | null}, measuring}` — measured in the background, see [SERVER-MODE.md](SERVER-MODE.md)), and `GET /api/users/audit[?limit=]` the staff reads of developers' sessions and admins' account changes (`reader`/`owner` are usernames, `reader_display`/`owner_display` their display names or null) (all `403 EADMIN` for a developer). See [SERVER-MODE.md](SERVER-MODE.md#what-each-user-sees).
+In server mode a **developer** sees only rows of the workspaces they own (`lanes.owner_id`): every list, count, chart and cost answer is limited to them, and a request naming another user's session, agent, workspace or run (in the path, query or body) answers `404 ENOTFOUND`. Admin and analyst see everything; `GET /api/users` lists every account (`displayName`, `email`, `createdAt`, `logins`, `lastLoginAt` included) with its workspaces, sessions and 7/30-day `{cost, tokens}`, `GET /api/users/storage[?refresh=1]` each user's home size (`{storage: {<id>: {bytes, files, partial, measuredAt} | null}, measuring}` — measured in the background, see [SERVER-MODE.md](SERVER-MODE.md)), `GET /api/users/tmux` each member's own tmux server under one Linux user per account (`{available, installed, matched, users: [{id, username, running, stuck?, version, pid, startedAt, sessions, busy, outdated}]}`; an admin's `POST /api/users/:id/tmux-restart` and `POST /api/users/tmux-restart-idle` restart them with `currentPassword`, audited, `409 ETMUXSTUCK` for a server that will not stop), and `GET /api/users/audit[?limit=]` the staff reads of developers' sessions and admins' account changes (`reader`/`owner` are usernames, `reader_display`/`owner_display` their display names or null) (all `403 EADMIN` for a developer). See [SERVER-MODE.md](SERVER-MODE.md#what-each-user-sees).
 
 An admin changes accounts with `POST /api/users` (`{username, password, role}` → `201 {user}`), `GET /api/users/:id` (`{user, workspaces: [{id, title, cwd}]}`, the account with `logins` and `lastLoginAt`, for the Edit form; admin or analyst), `GET /api/users/:id/avatar` (that account's picture for the sidebar's owner groups — admin or analyst, `nosniff` + `sandbox` CSP, `404 ENOAVATAR`; a workspace in `GET /api/lanes` carries `owner_avatar_at` to version its URL), `PATCH /api/users/:id` (any of `{displayName?, email?, role?, disabled?, password?, addWorkspaces?: [laneId], removeWorkspaces?: [laneId], signOut?: true}` — every field validated before any is written; `removeWorkspaces` leaves the workspace with no owner and answers `409 ENOTOWNED` for one the user does not own; an admin's own `password`/`signOut` keeps the login it came from), `POST /api/users/:id/password` (`{password}`; that user's logins end) `POST /api/users/:id/workspaces` (`{laneId}`; the workspace's owner becomes that user) and `DELETE /api/users/:id` (delete for good: the user's logins, panes, workspaces' records, prefs and — under S3 — their Linux account and whole home, removed FIRST so a refusal (`502 EPROVISION`) leaves every row; `409 ESELF` for yourself, `409 ELASTADMIN` for the last admin; session history and the audit log stay). Every one carries `currentPassword`, the admin's own password: `403 EREAUTH` when it is wrong or missing, `429 ETOOMANY` after 10 wrong tries in 15 minutes. `409 ESELF` for an admin's own role or disable, `409 EEXISTS` for a taken name, `400 EBADUSER`/`EBADPASSWORD`/`EBADROLE`/`EBADEMAIL`/`EBADFIELD`, `404 ENOUSER`/`ENOLANE`; a developer or analyst gets `403 EADMIN`, and local mode `403 ELOCALMODE`. No answer carries a password hash; each change is written to the audit log.
 

docs/SERVER-MODE.md

@@ -544,9 +544,9 @@ The pieces, and what each is for (the install steps are in the
 | `ah-<name>` | Made by `agenthub-provision`, not by the installer. One Linux user per AgentHub user, home `/srv/agenthub/users/<name>` (`0750`, group `agenthub`): the member owns it, the dashboard reads it, nobody else gets in. `.agenthub/{tmux,handoff}` (0700) is made by the member: their tmux socket, and the files the dashboard writes for their panes (as them) |
 | groups | `agenthub` (reads member homes: the host account), `agenthub-members` (every `ah-*` account), `agenthub-proc` (sees every process: the host account, `polkitd`) |
 | `agenthub.service` | A SYSTEM unit, `User=<host>`, with `SupplementaryGroups=agenthub agenthub-proc` and `AmbientCapabilities=CAP_DAC_READ_SEARCH`: the dashboard can read every member's tool files (Claude writes transcripts `0600`), but cannot write them. Every program it starts has the capability removed first (`setpriv`), so host panes, git and npm do not inherit it. It reads node and the plugin root from `<data dir>/runtime/agenthub.system.env`, a file the host owns, so a plugin update repoints it without root |
-| `/etc/sudoers.d/agenthub` | The host may run only `tmux`, `git`, `gh` (by the absolute paths recorded in `/etc/agenthub/server.conf`), `/opt/agenthub/libexec/write-as` and `/opt/agenthub/tools/bin/claude` (the [plugin baseline](#plugin-baseline-opt-in)) AS a member, plus, as root, only `/opt/agenthub/sbin/agenthub-provision` and `systemctl start/stop/restart/enable/disable agenthub.service`. Members are never in sudoers |
+| `/etc/sudoers.d/agenthub` | The host may run only `tmux`, `git`, `gh` (by the absolute paths recorded in `/etc/agenthub/server.conf`), `/opt/agenthub/libexec/tmux-member`, `/opt/agenthub/libexec/write-as` and `/opt/agenthub/tools/bin/claude` (the [plugin baseline](#plugin-baseline-opt-in)) AS a member, plus, as root, only `/opt/agenthub/sbin/agenthub-provision` and `systemctl start/stop/restart/enable/disable agenthub.service`. Members are never in sudoers |
 | `/etc/agenthub/server.conf` | Root's, `0644`: the host account and uid, the users root, the port, and the `tmux`/`git`/`gh` paths sudoers lists. Its presence turns S3 on |
-| `write-as`, `pane-launch` | `/opt/agenthub/libexec/`, root's. `write-as <path> [append\|replace\|private\|mkdir\|remove]` runs AS a member and does the one change, content on stdin. `pane-launch <file>` starts a member's pane from its launch file |
+| `write-as`, `pane-launch`, `tmux-member` | `/opt/agenthub/libexec/`, root's. `tmux-member -S <socket> …` runs a member's tmux call with their running server's own binary (else `TMUX_BIN`). `write-as <path> [append\|replace\|private\|mkdir\|remove]` runs AS a member and does the one change, content on stdin. `pane-launch <file>` starts a member's pane from its launch file |
 | `agenthub-provision` | The one root command besides `systemctl` on this unit: `create`, `disable` or `enable` `ah-<name>`. It refuses an account that exists outside `agenthub-members` and never deletes anything |
 | `/etc/claude-code/managed-settings.json` | Members' Claude Code hooks, through `/opt/agenthub/libexec/member-hook`, which does nothing for the host account (its plugin reports). A foreign file there is left alone |
 | `hidepid=invisible` | `/proc` (now and in `/etc/fstab`): an account sees only its own processes, so no member can read another's command line. A token passed with `tmux -e` is in one |
@@ -682,9 +682,22 @@ a pane really is. Each case below is refused or bounded, with a test in
   running host server uses that server's own binary (`/proc/<pid>/exe`, found
   from its socket in `/proc`), so installing a newer tmux under a running
   server no longer mixes versions: a 3.8 client asking a 3.6 server kept it at
-  100% CPU. A member's server is still asked with `TMUX_BIN` (the one path
+  100% CPU.
-  sudoers allows), so after a tmux upgrade restart each member's tmux server
+- **A member's tmux across a tmux upgrade.** Every tmux call AS a member goes
-  once it is idle (`sudo kill <pid>` of `tmux -S /srv/agenthub/users/<name>/.agenthub/tmux/sock`).
+  through `/opt/agenthub/libexec/tmux-member` (root's, in sudoers): it runs
+  the call with the binary of the member's running server (`/proc/<pid>/exe`,
+  found from their socket), else with `TMUX_BIN`, so a newer tmux never asks
+  an older server. Until `sudo agenthub server install-system` has installed
+  it, calls use `TMUX_BIN` directly, as before. A member's server keeps its
+  version until their last pane closes; the next start runs `TMUX_BIN`.
+- **Users → Members' tmux** (admin/analyst read, admin acts): each member's
+  running server with its version beside the installed one (an *older than
+  installed* badge), its sessions and whether an agent of theirs is working.
+  **Restart** ends one member's server — every pane of theirs closes, their
+  Claude sessions resume from the workspace — and **Restart N idle members**
+  does it for every outdated member with no agent working; both take the
+  admin's password again and are audited per member. A server that will not
+  stop answers `409 ETMUXSTUCK` naming its pid: root has to `kill -9` it.
 - **A member's huge or sparse files.** Transcripts and journals are read line
   by line with a 64 MiB cap per line (a 512 MB line used to crash the server);
   a whole member file is read only up to a cap (1 MiB for a login or a
@@ -746,10 +759,11 @@ itself, once.
 
 ### After an update that changes the member helpers
 
-`write-as`, `pane-launch` and the sudoers file are copied to
+`write-as`, `pane-launch`, `tmux-member` and the sudoers file are copied to
 `/opt/agenthub/libexec` by `install-system` only — an update of AgentHub does
 not touch root-owned files. When a release changes them (v2.7.7: `write-as`
-learned `move`/`copy` for the File Explorer), re-run it once:
+learned `move`/`copy` for the File Explorer; v2.8.4 added `tmux-member`),
+re-run it once:
 
 ```bash
 sudo agenthub server install-system
@@ -821,7 +835,7 @@ again changes nothing that is already in place):
       host account's);
    3. writes `/etc/agenthub/server.conf` (`HOST_USER`, `HOST_UID`,
       `USERS_ROOT`, `PORT`, `TMUX_BIN`, `GIT_BIN`, `GH_BIN`);
-   4. installs `agenthub-provision`, `write-as` and `pane-launch` from
+   4. installs `agenthub-provision`, `write-as`, `pane-launch` and `tmux-member` from
       `scripts/server/`;
    5. copies node to `/opt/agenthub/tools/node/<version>` (linked from
       `tools/bin/node`) and this install's `scripts/` and `server/lib/` to

scripts/server/install-system.sh

@@ -16,6 +16,7 @@
 #   /opt/agenthub/libexec/member-hook       Claude hook forwarder for members
 #   /opt/agenthub/libexec/write-as          writes in a member's home AS the member (sudo -u)
 #   /opt/agenthub/libexec/pane-launch       starts a member's pane from its launch file
+#   /opt/agenthub/libexec/tmux-member       a member's tmux, with their running server's own binary
 #   /etc/sudoers.d/agenthub       checked with visudo before it is installed
 #   /etc/claude-code/managed-settings.json  the member hooks (never over a foreign file)
 #   /proc hidepid=invisible,gid=agenthub-proc  (now and in /etc/fstab)
@@ -105,6 +106,7 @@ chmod 0644 /etc/agenthub/server.conf
 install -m 0755 -o root -g root "$ROOT/scripts/server/agenthub-provision.sh" /opt/agenthub/sbin/agenthub-provision
 install -m 0755 -o root -g root "$ROOT/scripts/server/write-as.sh" /opt/agenthub/libexec/write-as
 install -m 0755 -o root -g root "$ROOT/scripts/server/pane-launch.sh" /opt/agenthub/libexec/pane-launch
+install -m 0755 -o root -g root "$ROOT/scripts/server/tmux-member.sh" /opt/agenthub/libexec/tmux-member
 
 # ── node + the hook handler, for members (host-owned: the dashboard refreshes them) ──
 NODE_VER=$("$NODE" -p process.version)
@@ -138,7 +140,7 @@ visudo -cf "$TMP_SUDOERS" >/dev/null 2>&1 && NOTTY="Defaults:$HOST !requiretty"
 {
   echo "# AgentHub server mode (install-system). Members are never in sudoers."
   [ -z "$NOTTY" ] || echo "$NOTTY"
-  echo "$HOST ALL=(%agenthub-members) NOPASSWD:SETENV: $TMUX_BIN, $GIT_BIN${GH_BIN:+, $GH_BIN}, /opt/agenthub/libexec/write-as, /opt/agenthub/tools/bin/claude"
+  echo "$HOST ALL=(%agenthub-members) NOPASSWD:SETENV: $TMUX_BIN, /opt/agenthub/libexec/tmux-member, $GIT_BIN${GH_BIN:+, $GH_BIN}, /opt/agenthub/libexec/write-as, /opt/agenthub/tools/bin/claude"
   echo "$HOST ALL=(root) NOPASSWD: /opt/agenthub/sbin/agenthub-provision"
   for a in start stop restart enable disable; do
     [ "$a" = start ] || [ "$a" = stop ] || [ "$a" = restart ] && extra=" --no-block" || extra=""

scripts/server/tmux-member.sh

@@ -0,0 +1,34 @@
+#!/bin/bash
+# @file tmux-member.sh
+# @description Server mode, one Linux user per account (S3): installed as
+# /opt/agenthub/libexec/tmux-member, the one tmux the host may run AS a
+# member (sudoers). Called as `tmux-member -S <socket> <tmux args…>`, it runs
+# the args with the binary of the tmux server already listening on that
+# socket (`/proc/<pid>/exe`, which still runs after an upgrade replaced the
+# file), else with TMUX_BIN from /etc/agenthub/server.conf (no server yet:
+# this call starts one, on the installed version). A client must match its
+# server: a tmux 3.8 client asking a 3.6 server kept it at 100% CPU.
+#
+# It runs as the member and execs only a process THEY own (under hidepid they
+# see no other), so it can run nothing they could not run themselves.
+# @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+set -u
+bin=$(sed -n 's/^TMUX_BIN=//p' /etc/agenthub/server.conf 2>/dev/null | head -n 1)
+[[ "$bin" == /* ]] || { echo "tmux-member: no TMUX_BIN in /etc/agenthub/server.conf" >&2; exit 2; }
+if [ "${1:-}" = -S ] && [ -n "${2:-}" ]; then
+  # /proc/net/unix: Num RefCount Protocol Flags Type St Inode Path; 00010000 = listening.
+  inode=$(awk -v s="$2" '$4 == "00010000" && $8 == s { print $7; exit }' /proc/net/unix 2>/dev/null)
+  if [ -n "$inode" ]; then
+    for d in /proc/[0-9]*; do
+      [ -O "$d" ] || continue
+      read -r comm <"$d/comm" 2>/dev/null || continue
+      [[ "$comm" == tmux* ]] || continue
+      for fd in "$d"/fd/*; do
+        if [ "$(readlink "$fd" 2>/dev/null)" = "socket:[$inode]" ] && [ -x "$d/exe" ]; then
+          exec "$d/exe" "$@"
+        fi
+      done
+    done
+  fi
+fi
+exec "$bin" "$@"

server/__tests__/member-tmux.test.js

@@ -0,0 +1,186 @@
+/**
+ * @file Tests for each member's own tmux server on the Users page (S3,
+ * server/lib/member-tmux.js + `/api/users/tmux*`): its version beside the
+ * installed one, an admin's restart of one member (password again, audited,
+ * ETMUXSTUCK when it will not stop) and of every idle outdated member — a
+ * member whose agent is working is skipped. Member tmux calls are faked.
+ * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+ */
+
+const { describe, it, before, after } = require("node:test");
+const assert = require("node:assert/strict");
+const path = require("node:path");
+const fs = require("node:fs");
+const os = require("node:os");
+
+const TMP = fs.mkdtempSync(path.join(os.tmpdir(), "member-tmux-"));
+const USERS = path.join(TMP, "users");
+process.env.DASHBOARD_DB_PATH = path.join(TMP, "dashboard.db");
+process.env.DASHBOARD_LIVENESS_PROBE = "0";
+
+const { createApp, startServer } = require("../index");
+const { db } = require("../db");
+const auth = require("../lib/auth");
+const linux = require("../lib/linux-accounts");
+const tmux = require("../lib/tmux");
+
+let server;
+let BASE;
+const ids = {};
+const BOSS_PASS = "admin-pass-1";
+
+// Fake member tmux servers, by Linux login.
+const servers = {};
+function fakeMember(acct, args) {
+  const s = servers[acct.login];
+  if (!s || !s.alive) throw Object.assign(new Error("no server running"), { status: 1 });
+  if (args[0] === "display-message") return `${s.version}\t${s.pid}\t1700000000\t${s.sessions}\n`;
+  if (args[0] === "kill-server") {
+    if (s.stuck) throw Object.assign(new Error("server exited unexpectedly"), { status: 1 });
+    s.alive = false;
+    return "";
+  }
+  if (args[0] === "list-sessions") return "";
+  return "";
+}
+
+async function call(method, p, { cookie, body } = {}) {
+  const res = await fetch(BASE + p, {
+    method,
+    headers: { "Content-Type": "application/json", ...(cookie ? { cookie } : {}) },
+    body: body ? JSON.stringify(body) : undefined,
+  });
+  return { status: res.status, body: await res.json().catch(() => null) };
+}
+
+async function login(username, password) {
+  const res = await fetch(BASE + "/api/auth/login", {
+    method: "POST",
+    headers: { "Content-Type": "application/json" },
+    body: JSON.stringify({ username, password }),
+  });
+  return res.status === 200 ? res.headers.get("set-cookie").split(";")[0] : null;
+}
+
+before(async () => {
+  process.env.AGENTHUB_MODE = "server";
+  process.env.AGENTHUB_USERS_ROOT = USERS;
+  fs.mkdirSync(USERS, { recursive: true });
+  server = await startServer(createApp(), 0);
+  BASE = `http://127.0.0.1:${server.address().port}`;
+  ids.boss = (await auth.createUser("boss", BOSS_PASS, "admin")).id;
+  ids.mia = (await auth.createUser("mia", "member-pass-1", "developer")).id;
+  ids.zed = (await auth.createUser("zed", "member-pass-1", "developer")).id;
+  ids.ann = (await auth.createUser("ann", "member-pass-1", "developer")).id;
+  ids.stu = (await auth.createUser("stu", "member-pass-1", "developer")).id;
+  // zed's agent is working right now.
+  db.prepare(
+    "INSERT INTO lanes (cwd, tool, owner_id, status) VALUES (?, 'claude', ?, 'running')"
+  ).run(path.join(USERS, "zed", "p"), ids.zed);
+  // S3 on: a server.conf whose TMUX_BIN answers 3.8, and tmux-member installed.
+  const bin = path.join(TMP, "tmux");
+  fs.writeFileSync(bin, "#!/bin/sh\necho 'tmux 3.8'\n", { mode: 0o755 });
+  const wrapper = path.join(TMP, "tmux-member");
+  fs.writeFileSync(wrapper, "#!/bin/sh\n", { mode: 0o755 });
+  process.env.AGENTHUB_SERVER_CONF = path.join(TMP, "server.conf");
+  fs.writeFileSync(
+    process.env.AGENTHUB_SERVER_CONF,
+    `HOST_USER=h\nHOST_UID=1\nUSERS_ROOT=${USERS}\nTMUX_BIN=${bin}\nGIT_BIN=/usr/bin/git\n`
+  );
+  linux.__setTmuxMember(wrapper);
+  Object.assign(servers, {
+    "ah-mia": { version: "3.6", pid: 11, sessions: 2, alive: true },
+    "ah-zed": { version: "3.6", pid: 12, sessions: 1, alive: true },
+    "ah-ann": { version: "3.8", pid: 13, sessions: 3, alive: true },
+    "ah-stu": { version: "3.6", pid: 14, sessions: 1, alive: true, stuck: true },
+  });
+  tmux.__setAccountImpl(() => null, fakeMember);
+});
+
+after(() => {
+  delete process.env.AGENTHUB_MODE;
+  delete process.env.AGENTHUB_USERS_ROOT;
+  delete process.env.AGENTHUB_SERVER_CONF;
+  linux.__setTmuxMember("/opt/agenthub/libexec/tmux-member");
+  linux.__resetConfCache();
+  tmux.__reset();
+  server?.close();
+  fs.rmSync(TMP, { recursive: true, force: true });
+});
+
+describe("member tmux servers on the Users page", () => {
+  it("lists each member's version beside the installed one, and who is working", async () => {
+    const boss = await login("boss", BOSS_PASS);
+    const r = await call("GET", "/api/users/tmux", { cookie: boss });
+    assert.equal(r.status, 200);
+    assert.equal(r.body.available, true);
+    assert.equal(r.body.installed, "3.8");
+    assert.equal(r.body.matched, true);
+    const by = Object.fromEntries(r.body.users.map((u) => [u.username, u]));
+    assert.equal(by.mia.version, "3.6");
+    assert.equal(by.mia.outdated, true);
+    assert.equal(by.mia.sessions, 2);
+    assert.equal(by.zed.busy, 1);
+    assert.equal(by.ann.outdated, false);
+    // boss (no server of theirs) is listed as not running.
+    assert.equal(by.boss.running, false);
+  });
+
+  it("is staff-only to read and an admin's to restart", async () => {
+    const mia = await login("mia", "member-pass-1");
+    assert.equal((await call("GET", "/api/users/tmux", { cookie: mia })).status, 403);
+    const r = await call("POST", `/api/users/${ids.ann}/tmux-restart`, {
+      cookie: mia,
+      body: { currentPassword: "member-pass-1" },
+    });
+    assert.equal(r.status, 403);
+    assert.equal(servers["ah-ann"].alive, true);
+  });
+
+  it("restarts one member's server with the admin's password, audited", async () => {
+    const boss = await login("boss", BOSS_PASS);
+    const wrong = await call("POST", `/api/users/${ids.ann}/tmux-restart`, {
+      cookie: boss,
+      body: { currentPassword: "nope" },
+    });
+    assert.equal(wrong.body.error.code, "EREAUTH");
+    assert.equal(servers["ah-ann"].alive, true);
+    const ok = await call("POST", `/api/users/${ids.ann}/tmux-restart`, {
+      cookie: boss,
+      body: { currentPassword: BOSS_PASS },
+    });
+    assert.equal(ok.status, 200);
+    assert.equal(servers["ah-ann"].alive, false);
+    const audit = db
+      .prepare("SELECT path FROM audit_log WHERE owner_id = ? ORDER BY id DESC LIMIT 1")
+      .get(ids.ann);
+    assert.match(audit.path, /ann: tmux restarted \(was 3\.8, 3 session/);
+  });
+
+  it("names the pid to kill as root when a server will not stop", async () => {
+    const boss = await login("boss", BOSS_PASS);
+    const r = await call("POST", `/api/users/${ids.stu}/tmux-restart`, {
+      cookie: boss,
+      body: { currentPassword: BOSS_PASS },
+    });
+    assert.equal(r.status, 409);
+    assert.equal(r.body.error.code, "ETMUXSTUCK");
+    assert.match(r.body.error.message, /sudo kill -9 14/);
+  });
+
+  it("restarts every idle outdated member, skipping one whose agent works", async () => {
+    servers["ah-ann"] = { version: "3.8", pid: 13, sessions: 1, alive: true };
+    const boss = await login("boss", BOSS_PASS);
+    const r = await call("POST", "/api/users/tmux-restart-idle", {
+      cookie: boss,
+      body: { currentPassword: BOSS_PASS },
+    });
+    assert.equal(r.status, 200);
+    assert.deepEqual(r.body.restarted, ["mia"]);
+    assert.deepEqual(r.body.skipped, ["zed"]);
+    assert.equal(r.body.failed[0].username, "stu");
+    assert.equal(servers["ah-mia"].alive, false);
+    assert.equal(servers["ah-zed"].alive, true);
+    assert.equal(servers["ah-ann"].alive, true); // already on 3.8
+  });
+});

server/__tests__/server-s3-panes.test.js

@@ -240,9 +240,20 @@ describe("run-as: a path under the users root belongs to that user", () => {
       process.env.AGENTHUB_SERVER_CONF,
       `HOST_USER=h\nHOST_UID=1\nUSERS_ROOT=${TMP}/users\nGIT_BIN=/usr/bin/git\nTMUX_BIN=/opt/x/tmux\n`
     );
-    linux.__resetConfCache();
+    linux.__setTmuxMember(path.join(TMP, "no-tmux-member"));
     assert.equal(runAs.sudoArgv(ACCT, "git", ["status"])[1][3], "/usr/bin/git");
     assert.equal(runAs.sudoArgv(ACCT, "tmux", [])[1][3], "/opt/x/tmux");
+    // Once install-system put tmux-member there, a member's tmux goes through
+    // it (their running server's own binary); the installed one is still known.
+    const wrapper = path.join(TMP, "tmux-member");
+    fs.writeFileSync(wrapper, "#!/bin/sh\n", { mode: 0o755 });
+    linux.__setTmuxMember(wrapper);
+    try {
+      assert.equal(runAs.sudoArgv(ACCT, "tmux", [])[1][3], wrapper);
+      assert.equal(linux.serverConf().tmuxInstalled, "/opt/x/tmux");
+    } finally {
+      linux.__setTmuxMember(path.join(TMP, "no-tmux-member"));
+    }
     assert.equal(
       runAs.sudoArgv(ACCT, "/opt/agenthub/libexec/write-as", [])[1][3],
       "/opt/agenthub/libexec/write-as"

server/__tests__/server-s3-system.test.js

@@ -187,6 +187,7 @@ describe("Linux accounts", () => {
       hostUid: 4242,
       usersRoot: "/srv/agenthub/users",
       port: 4820,
+      tmuxInstalled: null,
       bins: {},
     });
     assert.deepEqual(linux.accountFor("mia"), {
@@ -199,7 +200,8 @@ describe("Linux accounts", () => {
     for (const bad of ["Mia", "1mia", "mi.a", "-x", "a".repeat(30), "root;id", "../x"]) {
       assert.throws(() => linux.provision("create", bad), { code: "EBADUSER" }, bad);
     }
-    assert.throws(() => linux.provision("delete", "mia"), /unknown provision action/);
+    // `delete` is an action now (Delete user); anything else is still refused.
+    assert.throws(() => linux.provision("purge", "mia"), /unknown provision action/);
     assert.deepEqual(argvs, []);
   });
 

server/lib/linux-accounts.js

@@ -46,6 +46,13 @@ function serverConf() {
   return confCache.value;
 }
 
+let TMUX_MEMBER = "/opt/agenthub/libexec/tmux-member";
+/** Test seam: where tmux-member is looked for. */
+function __setTmuxMember(p) {
+  TMUX_MEMBER = p;
+  confCache = { at: 0, path: null, value: null };
+}
+
 function readConf(file) {
   let text;
   try {
@@ -56,16 +63,28 @@ function readConf(file) {
   const get = (k) => new RegExp(`^${k}=(.*)$`, "m").exec(text)?.[1]?.trim() || "";
   const usersRoot = get("USERS_ROOT");
   if (!path.isAbsolute(usersRoot)) return null;
+  // A member's tmux runs through tmux-member once install-system put it there
+  // (and in sudoers): it picks their RUNNING server's own binary, so a tmux
+  // upgrade never mixes a new client with an old server. Before that, TMUX_BIN.
+  let tmuxBin = get("TMUX_BIN");
+  try {
+    fs.accessSync(TMUX_MEMBER, fs.constants.X_OK);
+    if (path.isAbsolute(tmuxBin)) tmuxBin = TMUX_MEMBER;
+  } catch {
+    /* not installed yet */
+  }
   return {
     hostUser: get("HOST_USER"),
     hostUid: Number(get("HOST_UID")),
     usersRoot,
     port: Number(get("PORT")) || null,
+    // The installed tmux (a new member server starts on it).
+    tmuxInstalled: path.isAbsolute(get("TMUX_BIN")) ? get("TMUX_BIN") : null,
     // The absolute paths sudoers lists (sudo would resolve a bare name on its
     // own secure_path, which may not be them).
     bins: Object.fromEntries(
       [
-        ["tmux", get("TMUX_BIN")],
+        ["tmux", tmuxBin],
         ["git", get("GIT_BIN")],
         ["gh", get("GH_BIN")],
       ].filter(([, v]) => path.isAbsolute(v))
@@ -154,6 +173,7 @@ function __resetConfCache() {
 
 module.exports = {
   __resetConfCache,
+  __setTmuxMember,
   confPath,
   LINUX_NAME_RE,
   serverConf,

server/lib/member-tmux.js

@@ -0,0 +1,103 @@
+/**
+ * @file member-tmux.js
+ * @description Server mode, one Linux user per account (S3): each member's
+ * own tmux server as the Users page shows it — the version it runs next to
+ * the installed one (`TMUX_BIN`), how many sessions it holds and whether an
+ * agent of theirs is working — and an admin's restart of it. A tmux server
+ * keeps the version it started with until its last session closes, so after
+ * a tmux upgrade an old server lingers; `tmux-member` (install-system) keeps
+ * every call on it matched to its own binary, and this is how an admin moves
+ * a member onto the new version on purpose. A restart ends every pane of
+ * theirs (their Claude sessions resume from the workspace).
+ * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+ */
+
+const { execFileSync } = require("node:child_process");
+
+const { db } = require("../db");
+const linux = require("./linux-accounts");
+const tmux = require("./tmux");
+
+const err = (code, message) => Object.assign(new Error(message), { code });
+
+// The installed tmux's version (`3.8`), re-read at most once a minute.
+let installed = { at: 0, bin: null, version: null };
+function installedVersion() {
+  const bin = linux.serverConf()?.tmuxInstalled || null;
+  if (installed.bin === bin && Date.now() - installed.at < 60_000) return installed.version;
+  let version = null;
+  if (bin) {
+    try {
+      version =
+        String(execFileSync(bin, ["-V"], { encoding: "utf8", timeout: 3000, stdio: "pipe" }))
+          .trim()
+          .replace(/^tmux\s+/, "") || null;
+    } catch {
+      /* missing or broken: unknown */
+    }
+  }
+  installed = { at: Date.now(), bin, version };
+  return version;
+}
+
+/** How many of `userId`'s workspaces have an agent working right now. */
+function busyCount(userId) {
+  return db
+    .prepare("SELECT COUNT(*) AS n FROM lanes WHERE owner_id = ? AND status = 'running'")
+    .get(userId).n;
+}
+
+/** One user's row; null for an account with no Linux side. */
+function rowFor(user, installedV) {
+  const acct = linux.accountFor(user.username);
+  if (!acct) return null;
+  const info = tmux.memberServerInfo(acct);
+  return {
+    id: user.id,
+    username: user.username,
+    ...info,
+    busy: busyCount(user.id),
+    outdated: !!(info.running && info.version && installedV && info.version !== installedV),
+  };
+}
+
+/** `{available, installed, matched, users: [...]}` for the Users page. */
+function overview(users) {
+  if (!linux.s3Enabled()) return { available: false, users: [] };
+  const conf = linux.serverConf();
+  const v = installedVersion();
+  return {
+    available: true,
+    installed: v,
+    // Whether calls on an older server already use its own binary.
+    matched: conf?.bins?.tmux !== conf?.tmuxInstalled,
+    users: users.map((u) => rowFor(u, v)).filter(Boolean),
+  };
+}
+
+/**
+ * Restart `user`'s tmux server. `{restarted: false}` when none ran; throws
+ * ETMUXSTUCK (with the pid) when it would not stop — root has to kill it.
+ */
+function restart(user) {
+  const acct = linux.accountFor(user.username);
+  if (!acct) throw err("ENOS3", "this account has no Linux user (S3 is not installed)");
+  const before = tmux.memberServerInfo(acct);
+  if (!before.running) return { restarted: false, before };
+  try {
+    tmux.killMemberServer(acct);
+  } catch {
+    /* judged by what is left below */
+  }
+  const after = tmux.memberServerInfo(acct);
+  if (after.running) {
+    const pid = before.pid || after.pid;
+    throw err(
+      "ETMUXSTUCK",
+      `${user.username}'s tmux server did not stop — run \`sudo kill -9 ${pid || "<pid>"}\` on the server`
+    );
+  }
+  return { restarted: true, before };
+}
+
+module.exports = { overview, restart, installedVersion };

server/lib/tmux.js

@@ -720,6 +720,53 @@ function killSession(name) {
   noteSession(name, accountOfQuiet(name), false);
 }
 
+/**
+ * A member's tmux server as the Users page shows it: `{running: false}`, or
+ * `{running: true, version, pid, startedAt, sessions}`, or `{stuck: true}`
+ * when it did not answer (hung, or backed off). Asked with `tmux-member`, i.e.
+ * with that server's own binary.
+ */
+function memberServerInfo(acct) {
+  try {
+    const out = String(
+      memberCall(acct, [
+        "display-message",
+        "-p",
+        "#{version}\t#{pid}\t#{start_time}\t#{server_sessions}",
+      ])
+    ).trim();
+    const [version, pid, start, sessions] = out.split("\t");
+    return {
+      running: true,
+      version: version || null,
+      pid: /^\d+$/.test(pid) ? Number(pid) : null,
+      startedAt: /^\d+$/.test(start) ? Number(start) * 1000 : null,
+      sessions: /^\d+$/.test(sessions) ? Number(sessions) : null,
+    };
+  } catch (err) {
+    if (err.code === "ETMUXHUNG" || err.code === "ETIMEDOUT" || err.code === "ENOBUFS") {
+      return { running: true, stuck: true };
+    }
+    // "no server running" / "error connecting": nothing to report.
+    return { running: false };
+  }
+}
+
+/**
+ * Stop a member's tmux server — every pane of theirs ends (an admin's Users
+ * page action, so the next start runs the installed tmux). Throws when the
+ * server did not go: a stuck one may need root (`sudo kill <pid>`).
+ */
+function killMemberServer(acct) {
+  unreachable.delete(acct.login); // asked deliberately, past any back-off
+  try {
+    memberCall(acct, ["kill-server"]);
+  } finally {
+    listGen++;
+    listed.delete(acct.login);
+  }
+}
+
 /** Session names starting with `prefix`. Empty array if tmux has no server running at all. */
 function listSessions(prefix) {
   const names = [];
@@ -867,6 +914,8 @@ module.exports = {
   upgradeAdvice,
   serverPid,
   memberAttach,
+  memberServerInfo,
+  killMemberServer,
   __setExecImpl,
   __setAccountImpl,
   __settle,

server/openapi-extra/auth.js

@@ -14,6 +14,8 @@
  *   - GET/PUT/DELETE /api/me/avatar (Auth) — the account's own picture
  *   - GET/PATCH /api/users/{id} (Auth) — the Users page's Edit user form
  *   - GET /api/users/{id}/avatar (Auth) — one account's picture (admin/analyst)
+ *   - GET /api/users/tmux, POST /api/users/{id}/tmux-restart, POST /api/users/tmux-restart-idle
+ *     (Auth) — each member's own tmux server and an admin's restart of it (S3)
  * Exports `{ tags, schemas, paths }`, combined into the spec by
  * server/openapi-extra.js. See docs/SERVER-MODE.md.
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
@@ -409,6 +411,77 @@ const paths = {
       },
     },
   },
+  "/api/users/tmux": {
+    get: {
+      tags: ["Auth"],
+      operationId: "listMemberTmux",
+      summary:
+        "Each member's own tmux server (one Linux user per account): its version beside the installed one, sessions, agents working (admin/analyst)",
+      responses: {
+        200: {
+          description:
+            "{available, installed, matched, users: [{id, username, running, stuck?, version, pid, startedAt, sessions, busy, outdated}]} — available false without S3",
+        },
+        403: err("EADMIN — a developer"),
+      },
+    },
+  },
+  "/api/users/{id}/tmux-restart": {
+    post: {
+      tags: ["Auth"],
+      operationId: "restartMemberTmux",
+      summary:
+        "End one member's tmux server — every pane of theirs closes; the next start runs the installed tmux (admin, own password again, audited)",
+      parameters: [idParam],
+      requestBody: {
+        required: true,
+        content: {
+          "application/json": {
+            schema: {
+              type: "object",
+              required: ["currentPassword"],
+              properties: { currentPassword: { type: "string" } },
+            },
+          },
+        },
+      },
+      responses: {
+        200: { description: "{user}" },
+        403: err("EREAUTH (own password wrong) / EADMIN / ELOCALMODE"),
+        404: err("ENOUSER"),
+        409: err(
+          "ETMUXSTUCK — the server did not stop (the message names the pid for root) / ENOS3"
+        ),
+      },
+    },
+  },
+  "/api/users/tmux-restart-idle": {
+    post: {
+      tags: ["Auth"],
+      operationId: "restartIdleMemberTmux",
+      summary:
+        "Restart every member server older than the installed tmux while no agent of theirs works (admin, own password again, audited per member)",
+      requestBody: {
+        required: true,
+        content: {
+          "application/json": {
+            schema: {
+              type: "object",
+              required: ["currentPassword"],
+              properties: { currentPassword: { type: "string" } },
+            },
+          },
+        },
+      },
+      responses: {
+        200: {
+          description:
+            "{restarted: [username], skipped: [username — an agent working], failed: [{username, message}]}",
+        },
+        403: err("EREAUTH / EADMIN / ELOCALMODE"),
+      },
+    },
+  },
   "/api/users/{id}/avatar": {
     get: {
       tags: ["Auth"],

server/routes/users.js

@@ -8,6 +8,12 @@
  * (server/lib/audit.js); `GET /storage` how much disk each user's home takes
  * (server/lib/user-storage.js — measured in a worker, `?refresh=1` re-measures).
  *
+ * `GET /tmux` (S3) is each member's own tmux server — its version beside the
+ * installed one, its sessions, whether an agent of theirs works — and an
+ * admin restarts one (`POST /:id/tmux-restart`) or every idle outdated one
+ * (`POST /tmux-restart-idle`), with their password again and audited
+ * (server/lib/member-tmux.js); a restart ends that member's panes.
+ *
  * `GET /:id` is one account with the workspaces it owns, for the Edit user form;
  * `GET /:id/avatar` its picture (server/lib/avatars.js), for the sidebar's
  * owner groups — staff only like the rest of `/users`.
@@ -96,6 +102,11 @@ router.get("/audit", (req, res) => {
   res.json({ entries: listAudit(req.query.limit) });
 });
 
+/** S3: each member's tmux server — its version beside the installed one (member-tmux.js). */
+router.get("/tmux", (_req, res) => {
+  res.json(require("../lib/member-tmux").overview(listUsers()));
+});
+
 const STATUS = {
   EBADUSER: 400,
   EBADEMAIL: 400,
@@ -114,6 +125,9 @@ const STATUS = {
   ETOOMANY: 429,
   // S3: the Linux account could not be created/locked (the helper said why).
   EPROVISION: 502,
+  ENOS3: 409,
+  // A member's tmux server that would not stop: root has to kill it.
+  ETMUXSTUCK: 409,
 };
 
 /**
@@ -290,6 +304,73 @@ router.delete(
   })
 );
 
+/**
+ * Restart one member's tmux server (every pane of theirs ends, so the next
+ * start runs the installed tmux) — the admin's password again, audited.
+ */
+router.post(
+  "/:id/tmux-restart",
+  accountChange(async (req) => {
+    const u = target(req);
+    const r = require("../lib/member-tmux").restart(u);
+    return {
+      user: auth.publicUser(u),
+      action: r.restarted
+        ? `${u.username}: tmux restarted (was ${r.before.version || "?"}, ${r.before.sessions ?? "?"} session(s))`
+        : `${u.username}: tmux restart — no server was running`,
+    };
+  })
+);
+
+/**
+ * Restart the tmux server of every member running an older tmux than the
+ * installed one while no agent of theirs works. One password, one audit
+ * entry per member restarted.
+ */
+router.post("/tmux-restart-idle", async (req, res) => {
+  try {
+    if (!auth.isServerMode() || !req.user) {
+      throw Object.assign(new Error("accounts are managed in server mode only"), {
+        code: "ELOCALMODE",
+      });
+    }
+    const body = req.body && typeof req.body === "object" ? req.body : {};
+    await auth.confirmPassword(req.user, body.currentPassword);
+    const mt = require("../lib/member-tmux");
+    const all = db.prepare("SELECT * FROM users ORDER BY id").all();
+    const rows = mt.overview(all.map(auth.publicUser)).users;
+    const restarted = [];
+    const skipped = [];
+    const failed = [];
+    for (const row of rows) {
+      if (!row.outdated) continue;
+      if (row.busy > 0) {
+        skipped.push(row.username);
+        continue;
+      }
+      const u = all.find((x) => x.id === row.id);
+      try {
+        const r = mt.restart(u);
+        if (!r.restarted) continue;
+        restarted.push(row.username);
+        recordAccountChange(
+          req.user.id,
+          u.id,
+          "POST",
+          `${u.username}: tmux restarted (idle, was ${row.version})`
+        );
+      } catch (e) {
+        failed.push({ username: row.username, message: e.message });
+      }
+    }
+    res.json({ restarted, skipped, failed });
+  } catch (err) {
+    const status = STATUS[err.code];
+    if (!status) return res.status(500).json({ error: { message: err.message } });
+    res.status(status).json({ error: { code: err.code, message: err.message } });
+  }
+});
+
 router.post(
   "/:id/password",
   accountChange(async (req, body) => {