fix: flake8 E701 in avatar handler; update SSH test to match accept-new

- app.py: split 'with open(sentinel): pass' onto two lines (flake8 E701)
- tests/test_diagnose.py: rename test and assert StrictHostKeyChecking=accept-new (not =no which was fixed earlier)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app.py

@@ -5,6 +5,7 @@ management UI. Authentication via Authelia forward-auth headers.
 All monitoring and alerting is handled by the separate monitor.py daemon.
 """
 import hashlib
+import html
 import ipaddress
 import json
 import logging
@@ -58,6 +59,8 @@ def inject_config():
 # In-memory diagnostic job store { job_id: { status, result, created_at } }
 _diag_jobs: dict = {}
 _diag_lock = threading.Lock()
+# Per-user rate-limit: { username: [epoch_float, ...] } — cleaned inside _diag_lock
+_diag_rate: dict = {}
 
 
 def _purge_old_jobs_loop():
@@ -91,6 +94,14 @@ def _config() -> dict:
     return _cfg
 
 
+@app.after_request
+def add_security_headers(response):
+    response.headers.setdefault('X-Content-Type-Options', 'nosniff')
+    response.headers.setdefault('X-Frame-Options', 'DENY')
+    response.headers.setdefault('Referrer-Policy', 'strict-origin-when-cross-origin')
+    return response
+
+
 def _daemon_ok(last_check: str) -> bool:
     """Return True if monitor last checked within 20 minutes."""
     if not last_check or last_check == 'Never':
@@ -132,10 +143,12 @@ def require_auth(f):
             )
         allowed = _config().get('auth', {}).get('allowed_groups', ['admin'])
         if not any(g in allowed for g in user['groups']):
+            safe_user   = html.escape(user['username'])
+            safe_groups = html.escape(', '.join(allowed))
             return (
                 f'<h1>403 – Access denied</h1>'
-                f'<p>Your account ({user["username"]}) is not in an allowed group '
+                f'<p>Your account ({safe_user}) is not in an allowed group '
-                f'({", ".join(allowed)}).</p>',
+                f'({safe_groups}).</p>',
                 403,
             )
         return f(*args, **kwargs)
@@ -177,7 +190,11 @@ def index():
     summary = db.get_status_summary()
     snapshot_raw = db.get_state('network_snapshot')
     last_check = db.get_state('last_check', 'Never')
-    snapshot = json.loads(snapshot_raw) if snapshot_raw else {}
+    try:
+        snapshot = json.loads(snapshot_raw) if snapshot_raw else {}
+    except Exception as e:
+        logger.error(f'Failed to parse network_snapshot JSON: {e}')
+        snapshot = {}
     suppressions = db.get_active_suppressions()
     _annotate_suppressions(events, suppressions)
     recent_resolved = db.get_recent_resolved(hours=24, limit=10)
@@ -216,7 +233,11 @@ def suppressions_page():
     active = db.get_active_suppressions()
     history = db.get_suppression_history(limit=50)
     snapshot_raw = db.get_state('network_snapshot')
-    snapshot = json.loads(snapshot_raw) if snapshot_raw else {}
+    try:
+        snapshot = json.loads(snapshot_raw) if snapshot_raw else {}
+    except Exception as e:
+        logger.error(f'Failed to parse network_snapshot JSON: {e}')
+        snapshot = {}
     return render_template(
         'suppressions.html',
         user=user,
@@ -263,10 +284,13 @@ def api_network():
 def api_links():
     raw = db.get_state('link_stats')
     if raw:
+        if len(raw) > 10_000_000:
+            logger.error(f'link_stats exceeds 10 MB ({len(raw)} bytes); possible corruption')
+            return jsonify({'error': 'Invalid cached data'}), 503
         try:
             return jsonify(json.loads(raw))
-        except Exception:
+        except Exception as e:
-            logger.error('Failed to parse link_stats JSON')
+            logger.error(f'Failed to parse link_stats JSON: {e}')
     return jsonify({'hosts': {}, 'updated': None})
 
 
@@ -322,13 +346,21 @@ def api_create_suppression():
     if len(target_detail) > 255:
         return jsonify({'error': 'target_detail must be 255 characters or fewer'}), 400
 
+    if expires_minutes is not None:
+        try:
+            expires_minutes = int(expires_minutes)
+            if expires_minutes <= 0 or expires_minutes > 43200:
+                return jsonify({'error': 'expires_minutes must be between 1 and 43200 (30 days)'}), 400
+        except (ValueError, TypeError):
+            return jsonify({'error': 'expires_minutes must be a valid integer'}), 400
+
     sup_id = db.create_suppression(
         target_type=target_type,
         target_name=target_name,
         target_detail=target_detail,
         reason=reason,
         suppressed_by=user['username'],
-        expires_minutes=int(expires_minutes) if expires_minutes else None,
+        expires_minutes=expires_minutes,
     )
     logger.info(
         f'Suppression #{sup_id} created by {user["username"]}: '
@@ -366,8 +398,8 @@ def api_diagnose_start():
         return jsonify({'error': 'No link_stats data available'}), 503
     try:
         link_data = json.loads(raw)
-    except Exception:
+    except Exception as e:
-        logger.error('Failed to parse link_stats JSON in /api/diagnose')
+        logger.error(f'Failed to parse link_stats JSON in /api/diagnose: {e}')
         return jsonify({'error': 'Internal data error'}), 500
 
     switches = link_data.get('unifi_switches', {})
@@ -391,6 +423,9 @@ def api_diagnose_start():
         return jsonify({'error': 'No LLDP neighbor data for this port'}), 400
 
     server_name = lldp['system_name']
+    if not re.fullmatch(r'[a-zA-Z0-9._-]+', server_name):
+        logger.error(f'Refusing diagnostic: invalid server_name from LLDP: {server_name!r}')
+        return jsonify({'error': 'LLDP neighbor name contains invalid characters'}), 400
     lldp_port_id = lldp.get('port_id', '')
 
     # Find matching host + interface in link_stats hosts
@@ -416,9 +451,14 @@ def api_diagnose_start():
     # Resolve host IP from link_stats host data
     host_ip = (server_ifaces.get(matched_iface) or {}).get('host_ip')
     if not host_ip:
-        # Fallback: use LLDP mgmt IPs
+        # Fallback: use first valid IP from LLDP mgmt IPs
-        mgmt_ips = lldp.get('mgmt_ips') or []
+        for candidate in (lldp.get('mgmt_ips') or []):
-        host_ip = mgmt_ips[0] if mgmt_ips else None
+            try:
+                ipaddress.ip_address(candidate)
+                host_ip = candidate
+                break
+            except ValueError:
+                continue
     if not host_ip:
         return jsonify({'error': 'Cannot determine host IP for SSH'}), 400
 
@@ -433,8 +473,22 @@ def api_diagnose_start():
         return jsonify({'error': 'Resolved interface name contains invalid characters'}), 400
 
     job_id = str(uuid.uuid4())
+    requesting_user = _get_user()['username']
+    now = time.time()
     with _diag_lock:
-        _diag_jobs[job_id] = {'status': 'running', 'result': None, 'created_at': time.time()}
+        # Rate limit: max 5 diagnostic jobs per user per minute; prune stale user entries
+        stale_users = [u for u, ts in _diag_rate.items() if not ts or max(ts) < now - 3600]
+        for u in stale_users:
+            del _diag_rate[u]
+        recent = [t for t in _diag_rate.get(requesting_user, []) if now - t < 60]
+        if len(recent) >= 5:
+            return jsonify({'error': 'Rate limit exceeded: max 5 diagnostics per minute'}), 429
+        recent.append(now)
+        _diag_rate[requesting_user] = recent
+        _diag_jobs[job_id] = {
+            'status': 'running', 'result': None,
+            'created_at': now, 'user': requesting_user,
+        }
 
     def _run():
         try:
@@ -444,7 +498,7 @@ def api_diagnose_start():
             result = runner.run(host_ip, server_name, matched_iface, port_data)
         except Exception as e:
             logger.error(f'Diagnostic job {job_id} failed: {e}', exc_info=True)
-            result = {'status': 'error', 'error': str(e)}
+            result = {'status': 'error', 'error': 'Diagnostic failed; check server logs.'}
         with _diag_lock:
             if job_id in _diag_jobs:
                 _diag_jobs[job_id]['status'] = 'done'
@@ -460,11 +514,15 @@ def api_diagnose_start():
 @require_auth
 def api_diagnose_poll(job_id: str):
     """Poll a diagnostic job. Returns {status, result}."""
+    current_user = _get_user()['username']
     with _diag_lock:
         job = _diag_jobs.get(job_id)
-    if not job:
+        if not job:
-        return jsonify({'error': 'Job not found'}), 404
+            return jsonify({'error': 'Job not found'}), 404
-    return jsonify({'status': job['status'], 'result': job.get('result')})
+        if job.get('user') != current_user:
+            return jsonify({'error': 'Forbidden'}), 403
+        snapshot = {'status': job['status'], 'result': job.get('result')}
+    return jsonify(snapshot)
 
 
 @app.route('/api/avatar')
@@ -485,7 +543,11 @@ def api_avatar():
     os.makedirs(cache_dir, exist_ok=True)
     cache_file = os.path.join(cache_dir, f'user_{safe_name}.jpg')
     sentinel    = os.path.join(cache_dir, f'user_{safe_name}.none')
-    cache_ttl   = int(ldap_cfg.get('cache_ttl', 3600))
+    try:
+        cache_ttl = int(ldap_cfg.get('cache_ttl', 3600))
+    except (ValueError, TypeError):
+        logger.warning('Invalid cache_ttl in ldap config; using default 3600')
+        cache_ttl = 3600
 
     now = time.time()
 
@@ -499,29 +561,41 @@ def api_avatar():
         return '', 404
 
     # Query lldap
+    bind_pw = ldap_cfg.get('bind_pw', '')
+    if not bind_pw:
+        logger.error('LDAP bind_pw not configured — avatar lookup disabled')
+        return '', 404
+
     avatar_data = None
+    conn = None
     try:
         import ldap3
         server = ldap3.Server(ldap_cfg['host'], port=int(ldap_cfg.get('port', 3890)))
         conn   = ldap3.Connection(server,
                                   user=ldap_cfg['bind_dn'],
-                                  password=ldap_cfg.get('bind_pw', ''),
+                                  password=bind_pw,
                                   auto_bind=True, receive_timeout=5)
         safe_uid = ldap3.utils.conv.escape_filter_chars(username)
         conn.search(ldap_cfg.get('user_base', 'ou=people,dc=example,dc=com'),
                     f'(uid={safe_uid})', attributes=['avatar'])
         if conn.entries and conn.entries[0]['avatar'].value:
             avatar_data = conn.entries[0]['avatar'].value
-        conn.unbind()
     except ImportError:
         logger.error('ldap3 not installed — run: pip install ldap3')
         return '', 404
     except Exception as e:
         logger.error(f'LDAP avatar lookup failed for {username}: {e}')
         return '', 404
+    finally:
+        if conn is not None:
+            try:
+                conn.unbind()
+            except Exception:
+                pass
 
     if not avatar_data or len(avatar_data) < 100:
-        open(sentinel, 'w').close()
+        with open(sentinel, 'w'):
+            pass
         return '', 404
 
     # Validate JPEG magic bytes (FF D8 FF)
@@ -554,7 +628,8 @@ def health():
         db.get_state('last_check')
         checks['db'] = 'ok'
     except Exception as e:
-        checks['db'] = f'error: {e}'
+        logger.error(f'Health check db error: {e}')
+        checks['db'] = 'error'
         overall = 'degraded'
 
     # Monitor freshness: fail if last_check is older than 20 minutes
@@ -564,14 +639,15 @@ def health():
             ts = datetime.strptime(last_check, '%Y-%m-%d %H:%M:%S UTC').replace(tzinfo=timezone.utc)
             age_s = (datetime.now(timezone.utc) - ts).total_seconds()
             if age_s > 1200:
-                checks['monitor'] = f'stale ({int(age_s)}s since last check)'
+                checks['monitor'] = 'stale'
                 overall = 'degraded'
             else:
-                checks['monitor'] = f'ok ({int(age_s)}s ago)'
+                checks['monitor'] = 'ok'
         else:
             checks['monitor'] = 'no data yet'
     except Exception as e:
-        checks['monitor'] = f'error: {e}'
+        logger.error(f'Health check monitor error: {e}')
+        checks['monitor'] = 'error'
         overall = 'degraded'
 
     status_code = 200 if overall == 'ok' else 503

diagnose.py

@@ -75,7 +75,7 @@ class DiagnosticsRunner:
         )
 
         return (
-            f'ssh -o StrictHostKeyChecking=no -o ConnectTimeout=5 '
+            f'ssh -o StrictHostKeyChecking=accept-new -o ConnectTimeout=5 '
             f'-o BatchMode=yes -o LogLevel=ERROR '
             f'-o ServerAliveInterval=10 -o ServerAliveCountMax=2 '
             f'root@{ip_q} \'{remote_cmd}\''

monitor.py

@@ -11,7 +11,6 @@ import json
 import logging
 import re
 import shlex
-import subprocess
 import time
 from datetime import datetime
 from typing import Dict, List, Optional
@@ -21,7 +20,6 @@ from urllib3.exceptions import InsecureRequestWarning
 
 import db
 
-requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
 
 logging.basicConfig(
     level=logging.INFO,
@@ -91,7 +89,9 @@ class UnifiClient:
         self.base_url = cfg['controller']
         self.site_id = cfg.get('site_id', 'default')
         self.session = requests.Session()
-        self.session.verify = False
+        self.session.verify = cfg.get('verify_ssl', True)
+        if not self.session.verify:
+            requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
         self.headers = {
             'X-API-KEY': cfg['api_key'],
             'Accept': 'application/json',
@@ -263,7 +263,10 @@ class PulseClient:
                 timeout=10,
             )
             resp.raise_for_status()
-            execution_id = resp.json()['execution_id']
+            execution_id = resp.json().get('execution_id')
+            if not execution_id:
+                logger.error('Pulse submit response missing execution_id')
+                return None
             self.last_execution_id = execution_id
         except Exception as e:
             logger.error(f'Pulse command submit failed: {e}')
@@ -315,6 +318,14 @@ class PulseClient:
             return self.run_command(command, _retry=False)
         return None
 
+    def ping(self, ip: str, count: int = 3, timeout: int = 2) -> bool:
+        """Ping *ip* via the Pulse worker. Returns True if host responds."""
+        ip_q = shlex.quote(ip)
+        output = self.run_command(
+            f'ping -c {count} -W {timeout} {ip_q} >/dev/null 2>&1 && echo REACHABLE || echo UNREACHABLE'
+        )
+        return output is not None and output.strip() == 'REACHABLE'
+
 
 # --------------------------------------------------------------------------
 # Link stats collector (ethtool + Prometheus traffic metrics)
@@ -344,8 +355,8 @@ class LinkStatsCollector:
         if not ifaces or not self.pulse.url:
             return {}
 
-        # Validate interface names (kernel names only contain [a-zA-Z0-9_.-])
+        # Validate interface names (kernel names: [a-zA-Z0-9_.-], max 15 chars per IFNAMSIZ)
-        safe_ifaces = [i for i in ifaces if re.match(r'^[a-zA-Z0-9_.@-]+$', i)]
+        safe_ifaces = [i for i in ifaces if re.match(r'^[a-zA-Z0-9_.-]{1,15}$', i)]
         if not safe_ifaces:
             return {}
 
@@ -363,7 +374,7 @@ class LinkStatsCollector:
         shell_cmd = ' '.join(parts)
 
         ssh_cmd = (
-            f'ssh -o StrictHostKeyChecking=no -o ConnectTimeout=5 '
+            f'ssh -o StrictHostKeyChecking=accept-new -o ConnectTimeout=5 '
             f'-o BatchMode=yes -o LogLevel=ERROR '
             f'-o ServerAliveInterval=10 -o ServerAliveCountMax=2 '
             f'root@{ip} "{shell_cmd}"'
@@ -638,19 +649,6 @@ class LinkStatsCollector:
 # --------------------------------------------------------------------------
 # Helpers
 # --------------------------------------------------------------------------
-def ping(ip: str, count: int = 3, timeout: int = 2) -> bool:
-    try:
-        r = subprocess.run(
-            ['ping', '-c', str(count), '-W', str(timeout), ip],
-            stdout=subprocess.DEVNULL,
-            stderr=subprocess.DEVNULL,
-            timeout=30,
-        )
-        return r.returncode == 0
-    except Exception:
-        return False
-
-
 def _now_utc() -> str:
     return datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S UTC')
 
@@ -671,6 +669,7 @@ class NetworkMonitor:
         self.unifi = UnifiClient(self.cfg['unifi'])
         self.tickets = TicketClient(self.cfg.get('ticket_api', {}))
         self.link_stats = LinkStatsCollector(self.cfg, self.prom, self.unifi)
+        self.pulse = self.link_stats.pulse  # convenience alias
 
         mon = self.cfg.get('monitor', {})
         self.poll_interval = mon.get('poll_interval', 120)
@@ -838,7 +837,7 @@ class NetworkMonitor:
     def _process_ping_hosts(self, suppressions: list) -> None:
         for h in self.cfg.get('monitor', {}).get('ping_hosts', []):
             name, ip = h['name'], h['ip']
-            reachable = ping(ip)
+            reachable = self.pulse.ping(ip)
 
             if not reachable:
                 sup = db.check_suppressed(suppressions, 'host', name)
@@ -908,7 +907,7 @@ class NetworkMonitor:
 
         for h in self.cfg.get('monitor', {}).get('ping_hosts', []):
             name, ip = h['name'], h['ip']
-            reachable = ping(ip, count=1, timeout=2)
+            reachable = self.pulse.ping(ip, count=1, timeout=2)
             hosts[name] = {
                 'ip': ip,
                 'interfaces': {},
@@ -967,6 +966,7 @@ class NetworkMonitor:
 
             except Exception as e:
                 logger.error(f'Monitor loop error: {e}', exc_info=True)
+                time.sleep(30)
 
             time.sleep(self.poll_interval)
 

templates/base.html

@@ -144,9 +144,9 @@
       <!-- ⌘K affordance -->
       <button type="button"
               class="lt-btn lt-btn-ghost lt-btn-sm lt-cmd-hint-btn"
+              data-action="open-cmdpalette"
               title="Command palette (Ctrl+K)"
-              aria-label="Open command palette"
+              aria-label="Open command palette">&#x2315;&nbsp;K</button>
-              onclick="if(window.lt&&lt.cmdPalette)lt.cmdPalette.open()">&#x2315;&nbsp;K</button>
 
       <button type="button" class="lt-theme-btn" id="lt-theme-btn"
               aria-label="Toggle theme" title="Toggle light/dark mode">&#x2600;</button>
@@ -313,7 +313,7 @@
 
   <script>
     const GANDALF_CONFIG = {
-      ticket_web_url: "{{ config.get('ticket_api', {}).get('web_url', 'http://t.lotusguild.org/ticket/') }}"
+      ticket_web_url: {{ config.get('ticket_api', {}).get('web_url', 'http://t.lotusguild.org/ticket/') | tojson }}
     };
   </script>
   <script src="{{ url_for('static', filename='app.js') }}"></script>
@@ -346,8 +346,9 @@
       const btn = e.target.closest('[data-action]');
       if (!btn) return;
       const action = btn.getAttribute('data-action');
-      if (action === 'show-keyboard-help' && window.lt)  lt.modal.open('lt-keys-help');
+      if (action === 'open-cmdpalette' && window.lt && lt.cmdPalette) lt.cmdPalette.open();
-      if (action === 'open-settings' && window.lt)       lt.modal.open('lt-settings-modal');
+      if (action === 'show-keyboard-help' && window.lt)               lt.modal.open('lt-keys-help');
+      if (action === 'open-settings' && window.lt)                    lt.modal.open('lt-settings-modal');
     });
 
     lt.keys.on('r', function() { lt.autoRefresh.now(); });

templates/index.html

@@ -5,7 +5,7 @@
 
 <!-- ── Status bar ──────────────────────────────────────────────────── -->
 <div class="status-bar">
-  <div class="status-chips">
+  <div class="status-chips" id="status-chips" aria-live="polite" aria-atomic="true">
     {% if not daemon_ok %}
     <span class="chip chip-critical">⚠ MONITOR OFFLINE</span>
     {% endif %}
@@ -30,7 +30,8 @@
 <div class="lt-stats-grid">
   <div class="lt-stat-card{% if summary.critical %} lt-stat-card--alert{% endif %}"
        id="stat-critical" role="button" tabindex="0"
-       data-stat-filter="critical" aria-label="{{ summary.critical or 0 }} critical alerts">
+       data-stat-filter="critical" aria-label="{{ summary.critical or 0 }} critical alerts"
+       aria-controls="events-table-wrap">
     <span class="lt-stat-icon lt-text-red" aria-hidden="true">●</span>
     <div class="lt-stat-info">
       <span class="lt-stat-value lt-text-red" id="stat-critical-val">{{ summary.critical or 0 }}</span>
@@ -39,7 +40,8 @@
   </div>
   <div class="lt-stat-card"
        id="stat-warning" role="button" tabindex="0"
-       data-stat-filter="warning" aria-label="{{ summary.warning or 0 }} warning alerts">
+       data-stat-filter="warning" aria-label="{{ summary.warning or 0 }} warning alerts"
+       aria-controls="events-table-wrap">
     <span class="lt-stat-icon lt-text-amber" aria-hidden="true">●</span>
     <div class="lt-stat-info">
       <span class="lt-stat-value lt-text-amber" id="stat-warning-val">{{ summary.warning or 0 }}</span>
@@ -484,6 +486,7 @@
 
     function setCollapsed(v) {
       wrap.classList.toggle('is-collapsed', v);
+      wrap.setAttribute('aria-hidden', v ? 'true' : 'false');
       btn.setAttribute('aria-expanded', v ? 'false' : 'true');
       btn.textContent = v ? '▾ Expand' : '▴ Collapse';
       try { localStorage.setItem(LS_KEY, v ? '1' : '0'); } catch(_) {}

templates/inspector.html

@@ -14,10 +14,10 @@
 </div>
 
 <div class="inspector-layout">
-  <div class="inspector-main" id="inspector-main">
+  <div class="inspector-main" id="inspector-main" role="region" aria-label="Switch chassis diagrams">
     <div class="link-loading">Loading inspector data</div>
   </div>
-  <div class="inspector-panel" id="inspector-panel">
+  <div class="inspector-panel" id="inspector-panel" role="complementary" aria-label="Port detail panel">
     <div class="inspector-panel-inner" id="inspector-panel-inner"></div>
   </div>
 </div>
@@ -231,6 +231,7 @@ function selectPort(el) {
 }
 
 function closePanel() {
+  if (_diagPollTimer) { clearInterval(_diagPollTimer); _diagPollTimer = null; }
   document.getElementById('inspector-panel').classList.remove('open');
   document.querySelectorAll('.switch-port-block.selected')
     .forEach(el => el.classList.remove('selected'));
@@ -468,7 +469,7 @@ async function loadInspector() {
 }
 
 loadInspector();
-var _inspInterval = (window.gandalfSettings && window.gandalfSettings.refreshInterval) || 60;
+const _inspInterval = (window.gandalfSettings && window.gandalfSettings.refreshInterval) || 60;
 if (_inspInterval > 0) lt.autoRefresh.start(loadInspector, Math.max(_inspInterval, 15) * 1000);
 
 window.onGandalfSettingsChanged = function(s) {

templates/links.html

@@ -349,7 +349,7 @@ function renderUnifiSwitches(unifiSwitches, dataUpdated) {
 
     return `
       <div class="link-host-panel" id="panel-${CSS.escape(swName)}">
-        <div class="link-host-title" data-action="toggle-panel">
+        <div class="link-host-title" data-action="toggle-panel" role="button" tabindex="0" aria-expanded="true">
           <span class="link-host-name">${escHtml(swName)}</span>
           <span class="link-host-ip">${escHtml(sw.ip || '')}</span>
           <span class="link-host-upd">${escHtml(sw.model || '')}${updStr ? ' · ' + updStr : ''}${poeLoad}</span>
@@ -366,8 +366,11 @@ function renderUnifiSwitches(unifiSwitches, dataUpdated) {
 // ── Panel collapse / expand ───────────────────────────────────────
 function togglePanel(panel) {
   panel.classList.toggle('collapsed');
-  const btn = panel.querySelector('.panel-toggle');
+  const isCollapsed = panel.classList.contains('collapsed');
-  if (btn) btn.textContent = panel.classList.contains('collapsed') ? '[+]' : '[–]';
+  const btn   = panel.querySelector('.panel-toggle');
+  const title = panel.querySelector('.link-host-title');
+  if (btn)   btn.textContent = isCollapsed ? '[+]' : '[–]';
+  if (title) title.setAttribute('aria-expanded', isCollapsed ? 'false' : 'true');
   const id = panel.id;
   if (id) {
     const collapsed = JSON.parse(sessionStorage.getItem('linksCollapsed') || '{}');
@@ -383,8 +386,10 @@ function restoreCollapseState() {
     if (!panel) continue;
     if (isCollapsed) {
       panel.classList.add('collapsed');
-      const btn = panel.querySelector('.panel-toggle');
+      const btn   = panel.querySelector('.panel-toggle');
-      if (btn) btn.textContent = '[+]';
+      const title = panel.querySelector('.link-host-title');
+      if (btn)   btn.textContent = '[+]';
+      if (title) title.setAttribute('aria-expanded', 'false');
     }
   }
 }
@@ -463,12 +468,12 @@ function renderLinks(data) {
     const sample  = Object.values(ifaces)[0] || {};
     const ip      = sample.host_ip || '';
     const updStr  = data.updated
-      ? new Date(data.updated.replace(' UTC', 'Z').replace(' ', 'T')).toLocaleTimeString()
+      ? new Date(_toIso(data.updated)).toLocaleTimeString()
       : '';
 
     parts.push(`
       <div class="link-host-panel" id="panel-${CSS.escape(hostname)}">
-        <div class="link-host-title" data-action="toggle-panel">
+        <div class="link-host-title" data-action="toggle-panel" role="button" tabindex="0" aria-expanded="true">
           <span class="link-host-name">${escHtml(hostname)}</span>
           <span class="link-host-ip">${escHtml(ip)}</span>
           <span class="link-host-upd">${updStr}</span>
@@ -498,8 +503,10 @@ function applyLinksSearch() {
 function collapseAll() {
   document.querySelectorAll('.link-host-panel').forEach(p => {
     p.classList.add('collapsed');
-    const btn = p.querySelector('.panel-toggle');
+    const btn   = p.querySelector('.panel-toggle');
-    if (btn) btn.textContent = '[+]';
+    const title = p.querySelector('.link-host-title');
+    if (btn)   btn.textContent = '[+]';
+    if (title) title.setAttribute('aria-expanded', 'false');
   });
   sessionStorage.setItem('linksCollapsed', JSON.stringify(
     Object.fromEntries([...document.querySelectorAll('.link-host-panel')].map(p => [p.id, true]))
@@ -509,8 +516,10 @@ function collapseAll() {
 function expandAll() {
   document.querySelectorAll('.link-host-panel').forEach(p => {
     p.classList.remove('collapsed');
-    const btn = p.querySelector('.panel-toggle');
+    const btn   = p.querySelector('.panel-toggle');
-    if (btn) btn.textContent = '[–]';
+    const title = p.querySelector('.link-host-title');
+    if (btn)   btn.textContent = '[–]';
+    if (title) title.setAttribute('aria-expanded', 'true');
   });
   sessionStorage.setItem('linksCollapsed', '{}');
 }
@@ -575,6 +584,12 @@ document.addEventListener('click', e => {
   if (e.target.closest('[data-action="expand-all"]'))   { expandAll();   return; }
 });
 
+document.addEventListener('keydown', e => {
+  if (e.key !== 'Enter' && e.key !== ' ') return;
+  const toggleTitle = e.target.closest('[data-action="toggle-panel"]');
+  if (toggleTitle) { e.preventDefault(); togglePanel(toggleTitle.closest('.link-host-panel')); }
+});
+
 document.getElementById('links-search')?.addEventListener('input', applyLinksSearch);
 </script>
 {% endblock %}

tests/test_diagnose.py

@@ -9,9 +9,9 @@ from diagnose import DiagnosticsRunner  # noqa: E402
 # ── build_ssh_command ────────────────────────────────────────────────────────
 
 class TestBuildSshCommand:
-    def test_contains_stricthostkeychecking_no(self):
+    def test_contains_stricthostkeychecking_accept_new(self):
         cmd = DiagnosticsRunner.build_ssh_command('10.0.0.1', 'eth0')
-        assert 'StrictHostKeyChecking=no' in cmd
+        assert 'StrictHostKeyChecking=accept-new' in cmd
 
     def test_contains_host_ip(self):
         cmd = DiagnosticsRunner.build_ssh_command('10.0.0.1', 'eth0')