Harden config sync defaults, crash resume, and network nav collapse.

Disable auto-sync by default, enforce single-flight cycles with crash requeue, delay new scheduled runs after restart, and make the network sidebar collapsible.

Co-authored-by: Cursor <cursoragent@cursor.com>

netx_api/config.py

@@ -75,6 +75,8 @@ class Settings(BaseSettings):
     # Config sync (periodic running-config backup into DB)
     config_sync_scheduler_enabled: bool = True
     config_sync_scheduler_tick_sec: int = 60
+    # After process start / unexpected restart, wait before any scheduled sync.
+    config_sync_startup_grace_sec: int = 3600
     # Managed NE exec: max CLI commands per request (lab can raise; hard-capped in ne_exec).
     ne_exec_max_commands: int = 5
     # WebCRT interactive terminal sessions

netx_api/config_sync_recovery.py

@@ -3,66 +3,112 @@
 from __future__ import annotations
 
 import logging
+from datetime import datetime
 
 from sqlalchemy.orm import Session
 
 from .config_sync_runner import dispatch_cycle
 from .config_sync_service import finalize_cycle, sync_cycle_progress
 from .models import ConfigSyncCycle, ConfigSyncTask
-from datetime import datetime
 
 _log = logging.getLogger("netx.config_sync.recovery")
 
+_ACTIVE = ("running", "paused", "pending")
+
+
+def _close_cycle(db: Session, cycle: ConfigSyncCycle, *, reason: str) -> None:
+    """Fail in-flight work and mark cycle terminal so it cannot block forever."""
+    cycle_id = str(cycle.id)
+    now = datetime.utcnow()
+    for task in (
+        db.query(ConfigSyncTask)
+        .filter(
+            ConfigSyncTask.cycle_id == cycle_id,
+            ConfigSyncTask.status.in_(("running", "pending")),
+        )
+        .all()
+    ):
+        was_running = str(task.status) == "running"
+        task.status = "fail" if was_running else "cancelled"
+        task.message = reason
+        task.ended_at = now
+    db.commit()
+    sync_cycle_progress(db, cycle_id)
+    db.refresh(cycle)
+    cycle.status = "fail"
+    cycle.error_message = reason
+    cycle.ended_at = now
+    db.commit()
+
 
 def recover_config_sync_on_startup(db: Session) -> int:
     """
-    Mark orphaned running tasks as fail(orphan_recovered), then resume pending
-    tasks for cycles still marked running/paused.
+    Resume at most one interrupted cycle after process restart.
+
+    Rules:
+    - Only one active cycle (running/pending/paused) may exist; older actives are closed.
+    - Orphan ``running`` tasks are re-queued to ``pending`` and continued (crash 续跑).
+    - ``paused`` cycles stay paused (no auto dispatch) but still occupy the single-flight slot.
+    - New scheduled cycles remain blocked while this active cycle exists.
     """
     cycles = (
         db.query(ConfigSyncCycle)
-        .filter(ConfigSyncCycle.status.in_(("running", "paused", "pending")))
+        .filter(ConfigSyncCycle.status.in_(_ACTIVE))
         .all()
     )
-    resumed = 0
-    for cycle in cycles:
-        cycle_id = str(cycle.id)
-        orphans = (
-            db.query(ConfigSyncTask)
-            .filter(ConfigSyncTask.cycle_id == cycle_id, ConfigSyncTask.status == "running")
-            .all()
+    cycles = sorted(cycles, key=lambda c: c.created_at or datetime.min)
+    if not cycles:
+        return 0
+
+    # Single-flight hygiene: keep newest, close older interrupted cycles.
+    primary = cycles[-1]
+    for stale in cycles[:-1]:
+        _log.warning(
+            "config_sync recovery closing older active cycle=%s (keep=%s)",
+            stale.id,
+            primary.id,
         )
-        for task in orphans:
-            task.status = "fail"
-            task.message = "orphan_recovered"
-            task.ended_at = datetime.utcnow()
-        if orphans:
-            db.commit()
-            _log.info("config_sync recovery cycle=%s orphaned_tasks=%s", cycle_id, len(orphans))
+        _close_cycle(db, stale, reason="superseded_active_cycle")
 
-        sync_cycle_progress(db, cycle_id)
-        db.refresh(cycle)
+    cycle_id = str(primary.id)
+    orphans = (
+        db.query(ConfigSyncTask)
+        .filter(ConfigSyncTask.cycle_id == cycle_id, ConfigSyncTask.status == "running")
+        .all()
+    )
+    for task in orphans:
+        task.status = "pending"
+        task.message = "requeued_after_restart"
+        task.started_at = None
+        task.ended_at = None
+    if orphans:
+        db.commit()
+        _log.info("config_sync recovery cycle=%s requeued_orphans=%s", cycle_id, len(orphans))
 
-        if str(cycle.status) == "paused":
-            continue
+    sync_cycle_progress(db, cycle_id)
+    db.refresh(primary)
 
-        pending = (
-            db.query(ConfigSyncTask)
-            .filter(ConfigSyncTask.cycle_id == cycle_id, ConfigSyncTask.status == "pending")
-            .count()
-        )
-        if pending <= 0:
-            if str(cycle.status) in ("running", "pending"):
-                finalize_cycle(db, cycle_id)
-            continue
+    if str(primary.status) == "paused":
+        _log.info("config_sync recovery cycle=%s stays paused (blocks new cycles)", cycle_id)
+        return 0
 
-        if str(cycle.status) == "pending":
-            cycle.status = "running"
-            if not cycle.started_at:
-                cycle.started_at = datetime.utcnow()
-            db.commit()
+    pending = (
+        db.query(ConfigSyncTask)
+        .filter(ConfigSyncTask.cycle_id == cycle_id, ConfigSyncTask.status == "pending")
+        .all()
+    )
+    if not pending:
+        finalize_cycle(db, cycle_id)
+        _log.info("config_sync recovery cycle=%s finalized (no pending)", cycle_id)
+        return 0
 
-        n = dispatch_cycle(cycle_id)
-        resumed += n
-        _log.info("config_sync recovery resumed cycle=%s pending=%s", cycle_id, n)
-    return resumed
+    if str(primary.status) == "pending":
+        primary.status = "running"
+        if not primary.started_at:
+            primary.started_at = datetime.utcnow()
+        db.commit()
+
+    task_ids = [str(t.id) for t in pending]
+    n = dispatch_cycle(cycle_id)
+    _log.info("config_sync recovery resumed cycle=%s pending=%s dispatched=%s", cycle_id, len(task_ids), n)
+    return n

netx_api/config_sync_runner.py

@@ -70,7 +70,7 @@ def _update_task(task_id: str, **fields: Any) -> None:
         db.close()
 
 
-def _update_task(task_id: str, **fields: Any) -> None:
+def _claim_task(cycle_id: str, task_id: str) -> bool:
     for attempt in range(10):
         db = SessionLocal()
         try:

netx_api/config_sync_scheduler.py

@@ -5,7 +5,7 @@ from __future__ import annotations
 import logging
 import threading
 import time
-from datetime import datetime
+from datetime import datetime, timedelta
 from uuid import uuid4
 
 from .config import settings
@@ -22,20 +22,50 @@ from .models import ConfigSyncCycle, ConfigSyncTask
 _log = logging.getLogger("netx.config_sync.scheduler")
 _stop = threading.Event()
 _thread: threading.Thread | None = None
+_BOOT_MONO = time.monotonic()
 
 
 def _utcnow() -> datetime:
     return datetime.utcnow()
 
 
+def startup_grace_remaining_sec() -> float:
+    grace = max(0, int(settings.config_sync_startup_grace_sec or 0))
+    elapsed = time.monotonic() - _BOOT_MONO
+    return max(0.0, float(grace) - elapsed)
+
+
+def in_startup_grace() -> bool:
+    return startup_grace_remaining_sec() > 0
+
+
+def startup_grace_until() -> datetime | None:
+    rem = startup_grace_remaining_sec()
+    if rem <= 0:
+        return None
+    return _utcnow() + timedelta(seconds=rem)
+
+
 def try_start_scheduled_cycle() -> str | None:
-    """Create and dispatch a scheduled cycle if policy is due. Returns cycle id or None."""
+    """Create and dispatch a scheduled cycle if policy is due. Returns cycle id or None.
+
+    Never starts while another cycle is active (running/pending/paused), including
+    a cycle being resumed after crash. Startup grace only delays *new* scheduled runs.
+    """
+    if in_startup_grace():
+        return None
     db = SessionLocal()
     try:
         policy = ensure_policy(db)
         if not policy.enabled:
             return None
-        if has_running_cycle(db):
+        active = has_running_cycle(db)
+        if active:
+            _log.debug(
+                "config_sync schedule skip: active cycle=%s status=%s",
+                active.id,
+                active.status,
+            )
             return None
         due = next_due_at(db, policy)
         if due is not None and due > _utcnow():
@@ -85,7 +115,8 @@ def try_start_scheduled_cycle() -> str | None:
 
 def _loop() -> None:
     tick = max(15, int(settings.config_sync_scheduler_tick_sec or 60))
-    _log.info("config_sync scheduler started tick=%ss", tick)
+    grace = max(0, int(settings.config_sync_startup_grace_sec or 0))
+    _log.info("config_sync scheduler started tick=%ss startup_grace=%ss", tick, grace)
     while not _stop.is_set():
         try:
             if bool(settings.config_sync_scheduler_enabled):

netx_api/config_sync_service.py

@@ -47,7 +47,7 @@ def _utcnow() -> datetime:
 def ensure_policy(db: Session) -> ConfigSyncPolicy:
     row = db.get(ConfigSyncPolicy, POLICY_ID)
     if row is None:
-        row = ConfigSyncPolicy(id=POLICY_ID)
+        row = ConfigSyncPolicy(id=POLICY_ID, enabled=False)
         db.add(row)
         db.commit()
         db.refresh(row)
@@ -202,15 +202,21 @@ def expand_targets(db: Session, policy: ConfigSyncPolicy) -> list[dict[str, str]
     return out
 
 
-def has_running_cycle(db: Session) -> ConfigSyncCycle | None:
+def has_active_cycle(db: Session) -> ConfigSyncCycle | None:
+    """Any non-terminal cycle occupies the single-flight slot (incl. paused)."""
     return (
         db.query(ConfigSyncCycle)
-        .filter(ConfigSyncCycle.status.in_(("running", "pending")))
+        .filter(ConfigSyncCycle.status.in_(("running", "pending", "paused")))
         .order_by(ConfigSyncCycle.created_at.desc())
         .first()
     )
 
 
+def has_running_cycle(db: Session) -> ConfigSyncCycle | None:
+    """Backward-compatible alias: treat paused as active so a new cycle cannot start."""
+    return has_active_cycle(db)
+
+
 def last_finished_cycle(db: Session) -> ConfigSyncCycle | None:
     return (
         db.query(ConfigSyncCycle)
@@ -224,6 +230,8 @@ def next_due_at(db: Session, policy: ConfigSyncPolicy | None = None) -> datetime
     pol = policy or ensure_policy(db)
     if not pol.enabled:
         return None
+    from .config_sync_scheduler import startup_grace_until
+
     last = (
         db.query(ConfigSyncCycle)
         .filter(ConfigSyncCycle.status == "success", ConfigSyncCycle.ended_at.isnot(None))
@@ -232,8 +240,14 @@ def next_due_at(db: Session, policy: ConfigSyncPolicy | None = None) -> datetime
     )
     days = max(1, int(pol.interval_days or 3))
     if last and last.ended_at:
-        return last.ended_at + timedelta(days=days)
-    return _utcnow()
+        due = last.ended_at + timedelta(days=days)
+    else:
+        # Never synced successfully: do not fire immediately on enable / first boot.
+        due = _utcnow() + timedelta(days=days)
+    grace_until = startup_grace_until()
+    if grace_until is not None and due < grace_until:
+        return grace_until
+    return due
 
 
 def create_cycle(db: Session, body: ConfigSyncCycleCreate) -> ConfigSyncCycleOut:

netx_api/main.py

@@ -840,7 +840,7 @@ def on_startup() -> None:
         ensure_policy(db)
         cfg_resumed = recover_config_sync_on_startup(db)
         if cfg_resumed:
-            _schedule_log.info("startup: resumed %s pending config_sync tasks", cfg_resumed)
+            _schedule_log.info("startup: resumed %s config_sync task(s) from interrupted cycle", cfg_resumed)
     except Exception:
         _schedule_log.exception("startup: ne collection / config_sync recovery failed")
     finally:

netx_api/models.py

@@ -492,7 +492,7 @@ class ConfigSyncPolicy(Base):
     __tablename__ = "config_sync_policy"
 
     id: Mapped[int] = mapped_column(Integer, primary_key=True, default=1)
-    enabled: Mapped[bool] = mapped_column(Boolean, default=True)
+    enabled: Mapped[bool] = mapped_column(Boolean, default=False)
     interval_days: Mapped[int] = mapped_column(Integer, default=3)
     concurrency: Mapped[int] = mapped_column(Integer, default=5)
     scope_mode: Mapped[str] = mapped_column(String(32), default="all")  # all | selected

tests/test_config_sync.py

@@ -211,33 +211,81 @@ class ConfigSyncRecoveryTests(unittest.TestCase):
     @patch("netx_api.config_sync_recovery.dispatch_cycle", return_value=2)
     @patch("netx_api.config_sync_recovery.finalize_cycle")
     @patch("netx_api.config_sync_recovery.sync_cycle_progress")
-    def test_orphan_running_tasks_marked_fail(self, _sync, _fin, dispatch):
+    def test_requeues_orphans_and_resumes(self, _sync, _fin, dispatch):
         cycle = MagicMock()
         cycle.id = "c1"
         cycle.status = "running"
+        cycle.created_at = datetime.now(timezone.utc)
         cycle.started_at = datetime.now(timezone.utc)
+        cycle.error_message = ""
+        cycle.ended_at = None
 
         orphan = MagicMock()
         orphan.status = "running"
         orphan.message = ""
+        orphan.started_at = datetime.now(timezone.utc)
         orphan.ended_at = None
 
+        pending = MagicMock()
+        pending.status = "pending"
+        pending.id = "t2"
+
         db = MagicMock()
         db.query.side_effect = [
             MagicMock(filter=MagicMock(return_value=MagicMock(all=MagicMock(return_value=[cycle])))),
             MagicMock(filter=MagicMock(return_value=MagicMock(all=MagicMock(return_value=[orphan])))),
-            MagicMock(filter=MagicMock(return_value=MagicMock(count=MagicMock(return_value=2)))),
+            MagicMock(
+                filter=MagicMock(
+                    return_value=MagicMock(all=MagicMock(return_value=[orphan, pending]))
+                )
+            ),
         ]
         db.refresh = MagicMock()
 
         resumed = recover_config_sync_on_startup(db)
 
-        self.assertEqual(orphan.status, "fail")
-        self.assertEqual(orphan.message, "orphan_recovered")
-        self.assertIsNotNone(orphan.ended_at)
+        self.assertEqual(orphan.status, "pending")
+        self.assertEqual(orphan.message, "requeued_after_restart")
+        self.assertIsNone(orphan.started_at)
         self.assertEqual(resumed, 2)
         dispatch.assert_called_once_with("c1")
 
+    @patch("netx_api.config_sync_recovery.dispatch_cycle")
+    @patch("netx_api.config_sync_recovery.finalize_cycle")
+    @patch("netx_api.config_sync_recovery.sync_cycle_progress")
+    def test_closes_older_active_keeps_newest(self, _sync, _fin, dispatch):
+        old = MagicMock()
+        old.id = "old"
+        old.status = "running"
+        old.created_at = datetime(2026, 1, 1, tzinfo=timezone.utc)
+        old.error_message = ""
+        old.ended_at = None
+
+        new = MagicMock()
+        new.id = "new"
+        new.status = "running"
+        new.created_at = datetime(2026, 1, 2, tzinfo=timezone.utc)
+        new.started_at = datetime.now(timezone.utc)
+        new.error_message = ""
+        new.ended_at = None
+
+        db = MagicMock()
+        db.query.side_effect = [
+            MagicMock(filter=MagicMock(return_value=MagicMock(all=MagicMock(return_value=[old, new])))),
+            MagicMock(filter=MagicMock(return_value=MagicMock(all=MagicMock(return_value=[])))),
+            MagicMock(filter=MagicMock(return_value=MagicMock(all=MagicMock(return_value=[])))),
+            MagicMock(filter=MagicMock(return_value=MagicMock(all=MagicMock(return_value=[])))),
+        ]
+        db.refresh = MagicMock()
+        dispatch.return_value = 0
+
+        recover_config_sync_on_startup(db)
+
+        self.assertEqual(old.status, "fail")
+        self.assertEqual(old.error_message, "superseded_active_cycle")
+        _fin.assert_called()
+        dispatch.assert_not_called()
+
 
 if __name__ == "__main__":
     unittest.main()

web/WEB.md

@@ -98,6 +98,10 @@ src/
 - 存储：PostgreSQL `ne_config_snapshot` / `ne_config_history`（zlib BYTEA）
 - 范围：ManagedNE + UME CLI 目标；厂商固定只读命令矩阵
 - 调度：`NETX_CONFIG_SYNC_SCHEDULER_ENABLED`（默认开），周期天数策略可配（默认 3 天）
+- 默认策略：`enabled=false`（首次无自动任务，需在页面手动开启周期调度或点「立即同步」）
+- 单飞：同一时刻只允许一个 `running|pending|paused` 周期；上轮未结束时不会开启新周期
+- 崩溃续跑：启动时把中断的 `running` 任务重新入队并继续，占用单飞槽位，避免与新周期重叠
+- 进程启动宽限：`NETX_CONFIG_SYNC_STARTUP_GRACE_SEC`（默认 3600）仅约束**新建**自动周期，不影响续跑
 - 前端：`/network/tasks/config-sync`（看板）+ `/network/configs`（查看）
 
 ## WebCRT

web/src/i18n/en.ts

@@ -55,6 +55,8 @@ const en = {
       configSync: "Config sync",
       portTraffic: "Port traffic",
     },
+    collapseNav: "Collapse sidebar",
+    expandNav: "Expand sidebar",
     placeholder: {
       title: "Coming soon",
       body: "This capability is not available yet.",

web/src/i18n/zh.ts

@@ -55,6 +55,8 @@ const zh = {
       configSync: "配置同步",
       portTraffic: "端口流量监控",
     },
+    collapseNav: "折叠侧栏",
+    expandNav: "展开侧栏",
     placeholder: {
       title: "功能规划中",
       body: "该能力尚未开放。",

web/src/index.css

@@ -2670,6 +2670,89 @@ pre {
   background: #f7f9fc;
   border-right: 1px solid #d0d7e2;
   min-height: 0;
+  transition: width 0.18s ease;
+}
+
+.network-shell.is-nav-collapsed .network-nav {
+  width: 48px;
+}
+
+.network-nav__head {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  padding: 10px 8px 8px 12px;
+  border-bottom: 1px solid #e2e8f0;
+  min-height: 44px;
+}
+
+.network-shell.is-nav-collapsed .network-nav__head {
+  justify-content: center;
+  padding: 10px 4px;
+}
+
+.network-nav__title {
+  flex: 1;
+  min-width: 0;
+  font-size: 13px;
+  font-weight: 700;
+  color: #0f172a;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.app-main .network-nav__collapse-btn,
+.network-nav__collapse-btn {
+  flex-shrink: 0;
+  width: 28px;
+  height: 28px;
+  padding: 0;
+  border: 1px solid #cbd5e1;
+  border-radius: 6px;
+  background: #fff;
+  color: #475569;
+  cursor: pointer;
+  line-height: 1;
+}
+
+.app-main .network-nav__collapse-btn:hover,
+.network-nav__collapse-btn:hover {
+  background: #eef2f7;
+  color: #0f172a;
+}
+
+.network-nav__rail {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 6px;
+  padding: 10px 4px;
+  overflow: auto;
+}
+
+.network-nav__rail-link {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  width: 32px;
+  height: 32px;
+  border-radius: 8px;
+  text-decoration: none;
+  color: #475569;
+  font-size: 12px;
+  font-weight: 700;
+  background: transparent;
+}
+
+.network-nav__rail-link:hover {
+  background: #eef2f7;
+  color: #0f172a;
+}
+
+.network-nav__rail-link.is-active {
+  background: #e3effc;
+  color: #1565c0;
 }
 
 .network-nav__scroll {

web/src/pages/ConfigSyncPage.tsx

@@ -31,7 +31,7 @@ export function ConfigSyncPage() {
   const [taskStatus, setTaskStatus] = useState("");
   const [taskKeyword, setTaskKeyword] = useState("");
 
-  const [enabled, setEnabled] = useState(true);
+  const [enabled, setEnabled] = useState(false);
   const [intervalDays, setIntervalDays] = useState(3);
   const [concurrency, setConcurrency] = useState(5);
   const [scopeMode, setScopeMode] = useState<"all" | "selected">("all");

web/src/pages/network/NetworkLayout.tsx

@@ -3,6 +3,8 @@ import { NavLink, Outlet, useLocation } from "react-router-dom";
 import { NETWORK_NAV, type NetworkNavGroupId } from "../../config/networkNav";
 import { useI18n } from "../../i18n";
 
+const SIDEBAR_KEY = "netx.network.sidebarCollapsed";
+
 function groupContainsPath(groupId: NetworkNavGroupId, pathname: string): boolean {
   const group = NETWORK_NAV.find((g) => g.id === groupId);
   if (!group) return false;
@@ -11,9 +13,18 @@ function groupContainsPath(groupId: NetworkNavGroupId, pathname: string): boolea
   );
 }
 
+function readSidebarCollapsed(): boolean {
+  try {
+    return localStorage.getItem(SIDEBAR_KEY) === "1";
+  } catch {
+    return false;
+  }
+}
+
 export function NetworkLayout() {
   const { t } = useI18n();
   const { pathname } = useLocation();
+  const [sidebarCollapsed, setSidebarCollapsed] = useState(readSidebarCollapsed);
   const [openGroups, setOpenGroups] = useState<Record<NetworkNavGroupId, boolean>>(() => {
     const init = {} as Record<NetworkNavGroupId, boolean>;
     for (const g of NETWORK_NAV) {
@@ -35,50 +46,95 @@ export function NetworkLayout() {
     setOpenGroups((prev) => ({ ...prev, [id]: !prev[id] }));
   };
 
+  const toggleSidebar = () => {
+    setSidebarCollapsed((prev) => {
+      const next = !prev;
+      try {
+        localStorage.setItem(SIDEBAR_KEY, next ? "1" : "0");
+      } catch {
+        // ignore
+      }
+      return next;
+    });
+  };
+
   return (
-    <div className="network-shell">
+    <div className={`network-shell${sidebarCollapsed ? " is-nav-collapsed" : ""}`}>
       <aside className="network-nav" aria-label={t("network.title")}>
-        <nav className="network-nav__scroll">
-          {NETWORK_NAV.map((group) => {
-            const open = Boolean(openGroups[group.id]);
-            const activeGroup = groupContainsPath(group.id, pathname);
-            return (
-              <div
-                key={group.id}
-                className={`network-nav__group${open ? " is-open" : ""}${activeGroup ? " is-active-group" : ""}`}
-              >
-                <button
-                  type="button"
-                  className="network-nav__group-toggle"
-                  aria-expanded={open}
-                  onClick={() => toggleGroup(group.id)}
+        <div className="network-nav__head">
+          {!sidebarCollapsed ? <span className="network-nav__title">{t("network.title")}</span> : null}
+          <button
+            type="button"
+            className="network-nav__collapse-btn"
+            title={sidebarCollapsed ? t("network.expandNav") : t("network.collapseNav")}
+            aria-label={sidebarCollapsed ? t("network.expandNav") : t("network.collapseNav")}
+            aria-expanded={!sidebarCollapsed}
+            onClick={toggleSidebar}
+          >
+            {sidebarCollapsed ? "»" : "«"}
+          </button>
+        </div>
+        {!sidebarCollapsed ? (
+          <nav className="network-nav__scroll">
+            {NETWORK_NAV.map((group) => {
+              const open = Boolean(openGroups[group.id]);
+              const activeGroup = groupContainsPath(group.id, pathname);
+              return (
+                <div
+                  key={group.id}
+                  className={`network-nav__group${open ? " is-open" : ""}${activeGroup ? " is-active-group" : ""}`}
                 >
-                  <span className="network-nav__chevron" aria-hidden>
-                    {open ? "▾" : "▸"}
-                  </span>
-                  <span className="network-nav__group-label">{t(group.labelKey)}</span>
-                </button>
-                {open ? (
-                  <ul className="network-nav__list">
-                    {group.items.map((item) => (
-                      <li key={item.id}>
-                        <NavLink
-                          to={item.path}
-                          className={({ isActive }) =>
-                            `network-nav__link${isActive ? " is-active" : ""}`
-                          }
-                          end={item.path === "/network/devices"}
-                        >
-                          {t(item.labelKey)}
-                        </NavLink>
-                      </li>
-                    ))}
-                  </ul>
-                ) : null}
-              </div>
-            );
-          })}
-        </nav>
+                  <button
+                    type="button"
+                    className="network-nav__group-toggle"
+                    aria-expanded={open}
+                    onClick={() => toggleGroup(group.id)}
+                  >
+                    <span className="network-nav__chevron" aria-hidden>
+                      {open ? "▾" : "▸"}
+                    </span>
+                    <span className="network-nav__group-label">{t(group.labelKey)}</span>
+                  </button>
+                  {open ? (
+                    <ul className="network-nav__list">
+                      {group.items.map((item) => (
+                        <li key={item.id}>
+                          <NavLink
+                            to={item.path}
+                            className={({ isActive }) =>
+                              `network-nav__link${isActive ? " is-active" : ""}`
+                            }
+                            end={item.path === "/network/devices"}
+                          >
+                            {t(item.labelKey)}
+                          </NavLink>
+                        </li>
+                      ))}
+                    </ul>
+                  ) : null}
+                </div>
+              );
+            })}
+          </nav>
+        ) : (
+          <nav className="network-nav__rail" aria-label={t("network.title")}>
+            {NETWORK_NAV.flatMap((group) =>
+              group.items.map((item) => (
+                <NavLink
+                  key={item.id}
+                  to={item.path}
+                  title={t(item.labelKey)}
+                  className={({ isActive }) =>
+                    `network-nav__rail-link${isActive ? " is-active" : ""}`
+                  }
+                  end={item.path === "/network/devices"}
+                >
+                  {t(item.labelKey).slice(0, 1)}
+                </NavLink>
+              )),
+            )}
+          </nav>
+        )}
       </aside>
       <div className="network-main">
         <Outlet />