feat(balancer): add balancer-to-balancer fallback support

Xray does not natively support using a balancer as fallbackTag for
another balancer. This feature automates the loopback workaround:
when a user selects a balancer as fallback, the panel generates a
loopback outbound + routing rule in the template.

How it works:
- User picks fallback balancer from dropdown
- Panel creates loopback outbound _bl_{target} + routing rule
- Balancer fallbackTag set to _bl_{target}
- Traffic: Balancer A → loopback _bl_B → routing rule → Balancer B

Key features:
- Dedup: multiple balancers sharing same fallback reuse one loopback
- DFS cycle detection at edit time and on save
- Self-reference guard (cannot select own balancer)
- Delete protection (blocks if used as fallback by others)
- Cleans up routing rules referencing deleted balancers
- Override resolves balancer tags through loopback mechanism
- All live status tags resolved for display
- Internal _bl_ objects filtered from Outbounds/Routing UI
- Backward-compatible with old _bl_ naming format
- Translations for all 13 locales

frontend/src/pages/xray/XrayPage.tsx

@@ -30,6 +30,7 @@ import { propagateOutboundTagRename } from './basics/helpers';
 import { RoutingTab } from './routing';
 import { OutboundsTab } from './outbounds';
 import { BalancersTab } from './balancers';
+import { cleanupOrphanedBalancerLoopbacks, ensureMissingBalancerLoopbacks, detectBalancerCycles } from './balancers/balancer-loopback';
 import { DnsTab } from './dns';
 import { WarpModal, NordModal } from './overrides';
 import './XrayPage.css';
@@ -190,6 +191,18 @@ export default function XrayPage() {
       navigate('/xray#advanced');
       return;
     }
+    if (templateSettings) {
+      const clone = JSON.parse(JSON.stringify(templateSettings));
+      ensureMissingBalancerLoopbacks(clone);
+      cleanupOrphanedBalancerLoopbacks(clone);
+      const cycles = detectBalancerCycles(clone);
+      if (cycles.length > 0) {
+        const names = cycles.map((c) => c.join(' → ')).join(', ');
+        messageApi.error(t('pages.xray.balancer.balancerFallbackCycle') + ' (' + names + ')');
+        return;
+      }
+      setTemplateSettings(clone);
+    }
     saveAll();
   }
 

frontend/src/pages/xray/balancers/BalancerFormModal.tsx

@@ -1,9 +1,10 @@
 import { useMemo, useState } from 'react';
 import { useTranslation } from 'react-i18next';
-import { Button, Form, Input, InputNumber, Modal, Select, Space, Switch } from 'antd';
+import { Alert, Button, Form, Input, InputNumber, Modal, Select, Space, Switch, Tag } from 'antd';
 import { MinusOutlined, PlusOutlined } from '@ant-design/icons';
 
 import { InputAddon } from '@/components/ui';
+import type { XraySettingsValue } from '@/hooks/useXraySetting';
 import {
   BalancerFormSchema,
   type BalancerFormValues,
@@ -12,7 +13,9 @@ import {
   BalancerStrategyTypeSchema,
   type BalancerStrategySettings,
   type BalancerStrategyType,
+  type BalancerObject,
 } from '@/schemas/routing';
+import { isBalancerLoopbackTag } from './balancer-loopback';
 
 export type BalancerFormValue = BalancerFormValues;
 
@@ -20,6 +23,9 @@ interface BalancerFormModalProps {
   open: boolean;
   balancer: BalancerFormValue | null;
   outboundTags: string[];
+  balancerTags: string[];
+  balancers: BalancerObject[];
+  templateSettings: XraySettingsValue | null;
   otherTags: string[];
   onClose: () => void;
   onConfirm: (value: BalancerFormValue) => void;
@@ -62,6 +68,9 @@ export default function BalancerFormModal({
   open,
   balancer,
   outboundTags,
+  balancerTags,
+  balancers,
+  templateSettings,
   otherTags,
   onClose,
   onConfirm,
@@ -125,9 +134,79 @@ export default function BalancerFormModal({
   const baselines = settings?.baselines ?? [];
   const costs = settings?.costs ?? [];
 
-  const fallbackOptions = useMemo(
-    () => ['', ...outboundTags].map((tg) => ({ value: tg, label: tg || `(${t('none')})` })),
-    [outboundTags, t],
+  const currentTag = state.tag.trim();
+
+  const availableBalancerTags = useMemo(() => {
+    return balancerTags.filter((tg) => tg !== currentTag);
+  }, [balancerTags, currentTag]);
+
+  const cycleInfo = useMemo(() => {
+    const rules = (templateSettings?.routing?.rules || []) as Array<{ inboundTag?: string[]; balancerTag?: string }>;
+    const resolveLoopback = (tag: string): string | null => {
+      for (const r of rules) {
+        if (Array.isArray(r.inboundTag) && r.inboundTag.includes(tag) && r.balancerTag) {
+          return r.balancerTag;
+        }
+      }
+      return null;
+    };
+
+    const fallbackOf: Record<string, string> = {};
+    for (const b of balancers) {
+      if (!b.tag || !b.fallbackTag || b.tag === currentTag) continue;
+      const target = isBalancerLoopbackTag(b.fallbackTag)
+        ? resolveLoopback(b.fallbackTag)
+        : b.fallbackTag;
+      if (target) fallbackOf[b.tag] = target;
+    }
+
+    const result: Record<string, string[]> = {};
+    for (const tg of availableBalancerTags) {
+      const visited = new Set<string>();
+      let cursor = tg;
+      const path = [tg];
+      while (cursor && !visited.has(cursor)) {
+        if (cursor === currentTag) {
+          result[tg] = path;
+          break;
+        }
+        visited.add(cursor);
+        cursor = fallbackOf[cursor] || '';
+        if (cursor) path.push(cursor);
+      }
+    }
+    return result;
+  }, [currentTag, balancers, availableBalancerTags, templateSettings?.routing?.rules]);
+
+  const wouldCreateCycle = !!cycleInfo[state.fallbackTag];
+
+  const fallbackOptions = useMemo(() => {
+    const options: Array<{ value: string; label: React.ReactNode; disabled?: boolean; title?: string }> = [
+      { value: '', label: `(${t('none')})` },
+    ];
+    for (const tg of outboundTags) {
+      options.push({ value: tg, label: tg });
+    }
+    for (const tg of availableBalancerTags) {
+      const cycle = cycleInfo[tg];
+      options.push({
+        value: tg,
+        disabled: !!cycle,
+        title: cycle ? t('pages.xray.balancer.cycleTooltip', { path: cycle.join(' → '), start: currentTag }) : undefined,
+        label: (
+          <span>
+            <Tag color="blue" style={{ marginRight: 4 }}>{t('pages.xray.rules.balancer')}</Tag>
+            {tg}
+          </span>
+        ),
+      });
+    }
+    return options;
+  }, [outboundTags, availableBalancerTags, cycleInfo, currentTag, t]);
+
+  const isFallbackBalancer = useMemo(
+    () => balancerTags.includes(state.fallbackTag),
+    [balancerTags, state.fallbackTag],
   );
 
   const title = isEdit
@@ -141,6 +220,7 @@ export default function BalancerFormModal({
       title={title}
       okText={okText}
       cancelText={t('close')}
+      okButtonProps={{ disabled: !parsed.success || duplicateTag || wouldCreateCycle }}
       mask={{ closable: false }}
       onOk={submit}
       onCancel={onClose}
@@ -189,6 +269,22 @@ export default function BalancerFormModal({
             options={fallbackOptions}
           />
         </Form.Item>
+        {isFallbackBalancer && !wouldCreateCycle && (
+          <Alert
+            type="info"
+            showIcon
+            message={t('pages.xray.balancer.balancerFallbackInfo')}
+            style={{ marginBottom: 16 }}
+          />
+        )}
+        {wouldCreateCycle && (
+          <Alert
+            type="error"
+            showIcon
+            message={t('pages.xray.balancer.balancerFallbackCycle')}
+            style={{ marginBottom: 16 }}
+          />
+        )}
 
         {state.strategy === 'leastLoad' && (
           <>

frontend/src/pages/xray/balancers/BalancersTab.tsx

@@ -1,12 +1,21 @@
 import { useCallback, useEffect, useMemo, useState } from 'react';
 import { useTranslation } from 'react-i18next';
-import { Button, Dropdown, Empty, Modal, Select, Space, Table, Tabs, Tag, Tooltip } from 'antd';
+import { Button, Dropdown, Empty, Modal, Select, Space, Table, Tabs, Tag, Tooltip, message } from 'antd';
 import { PlusOutlined, MoreOutlined, EditOutlined, DeleteOutlined, SyncOutlined, DeploymentUnitOutlined, RadarChartOutlined } from '@ant-design/icons';
 import type { ColumnsType } from 'antd/es/table';
 
 import BalancerFormModal from './BalancerFormModal';
 import type { BalancerFormValue } from './BalancerFormModal';
 import { syncObservatories, observersRemovedByDeletingBalancer } from './balancer-helpers';
+import {
+  isBalancerLoopbackTag,
+  loopbackTagFor,
+  resolveLoopbackFallback,
+  ensureBalancerLoopback,
+  removeBalancerLoopback,
+  removeBalancerLoopbackIfOrphaned,
+  propagateBalancerTagRename,
+} from './balancer-loopback';
 import ObservatorySettingsTab from './ObservatorySettingsTab';
 import { catTabLabel } from '@/pages/settings/catTabLabel';
 import { HttpUtil } from '@/utils';
@@ -42,6 +51,7 @@ interface BalancerRow {
   strategy: BalancerStrategyType;
   selector: string[];
   fallbackTag: string;
+  displayFallbackTag: string;
   settings?: BalancerStrategySettings;
 }
 
@@ -61,26 +71,33 @@ export default function BalancersTab({
 }: BalancersTabProps) {
   const { t } = useTranslation();
   const [modal, modalContextHolder] = Modal.useModal();
+  const [messageApi, messageContextHolder] = message.useMessage();
   const [modalOpen, setModalOpen] = useState(false);
   const [editingBalancer, setEditingBalancer] = useState<BalancerFormValue | null>(null);
   const [editingIndex, setEditingIndex] = useState<number | null>(null);
 
+  const balancerObjects = useMemo(
+    () => (templateSettings?.routing?.balancers || []) as BalancerObject[],
+    [templateSettings?.routing?.balancers],
+  );
+
   const rows: BalancerRow[] = useMemo(() => {
-    const list = (templateSettings?.routing?.balancers || []) as BalancerRecord[];
+    const list = balancerObjects;
     return list.map((b, idx) => ({
       key: idx,
       tag: b.tag || '',
       strategy: (b.strategy?.type ?? 'random') as BalancerStrategyType,
       selector: b.selector || [],
       fallbackTag: b.fallbackTag || '',
+      displayFallbackTag: resolveLoopbackFallback(templateSettings!, b.fallbackTag || ''),
       settings: b.strategy?.settings,
     }));
-  }, [templateSettings?.routing?.balancers]);
+  }, [balancerObjects, templateSettings]);
 
   const outboundTags = useMemo(() => {
     const tags = new Set<string>();
     for (const o of templateSettings?.outbounds || []) {
-      if (o?.tag) tags.add(o.tag);
+      if (o?.tag && !isBalancerLoopbackTag(o.tag)) tags.add(o.tag);
     }
     for (const tag of clientReverseTags || []) {
       if (tag) tags.add(tag);
@@ -96,6 +113,14 @@ export default function BalancersTab({
     return rows.filter((b) => b.key !== editingIndex).map((b) => b.tag).filter(Boolean);
   }, [rows, editingIndex]);
 
+  const balancerTags = useMemo(() => {
+    return otherTags.filter((tg) => !isBalancerLoopbackTag(tg));
+  }, [otherTags]);
+
+  const overrideOptions: Array<{ value: string; label: React.ReactNode }> = useMemo(() => {
+    return outboundTags.map((tag) => ({ value: tag, label: tag }));
+  }, [outboundTags]);
+
   const mutate = useCallback(
     (mutator: (next: XraySettingsValue) => void) => {
       setTemplateSettings((prev) => {
@@ -146,7 +171,12 @@ export default function BalancersTab({
     setModalOpen(true);
   }
   function openEdit(idx: number) {
-    setEditingBalancer(rows[idx]);
+    const row = rows[idx];
+    const resolved: BalancerFormValue = {
+      ...row,
+      fallbackTag: resolveLoopbackFallback(templateSettings!, row.fallbackTag),
+    };
+    setEditingBalancer(resolved);
     setEditingIndex(idx);
     setModalOpen(true);
   }
@@ -156,10 +186,11 @@ export default function BalancersTab({
       if (!tt.routing) tt.routing = { rules: [], balancers: [] };
       if (!Array.isArray(tt.routing.balancers)) tt.routing.balancers = [];
       const list = tt.routing.balancers as BalancerRecord[];
+
       const wire: BalancerRecord = {
         tag: form.tag,
         selector: [...form.selector],
-        fallbackTag: form.fallbackTag || '',
+        fallbackTag: '',
       };
       if (form.strategy && form.strategy !== 'random') {
         wire.strategy = { type: form.strategy };
@@ -167,16 +198,42 @@ export default function BalancersTab({
           wire.strategy.settings = form.settings;
         }
       }
+
+      const isFallbackABalancer = form.fallbackTag && balancerTags.includes(form.fallbackTag);
+
+      if (isFallbackABalancer) {
+        wire.fallbackTag = loopbackTagFor(form.fallbackTag);
+      } else {
+        wire.fallbackTag = form.fallbackTag || '';
+      }
+
       if (editingIndex == null) {
         list.push(wire);
+        if (isFallbackABalancer) {
+          ensureBalancerLoopback(tt, form.fallbackTag);
+        }
       } else {
         const oldTag = list[editingIndex]?.tag;
+        const oldFallback = list[editingIndex]?.fallbackTag || '';
         list[editingIndex] = wire;
+
         if (oldTag && oldTag !== wire.tag) {
           const rules = tt.routing.rules || [];
           for (const rule of rules) {
             if (rule?.balancerTag === oldTag) rule.balancerTag = wire.tag;
           }
+          propagateBalancerTagRename(tt, oldTag, wire.tag);
+        }
+
+        const oldTarget = isBalancerLoopbackTag(oldFallback)
+          ? (oldFallback.slice(4))
+          : null;
+
+        if (oldTarget && oldTarget !== form.fallbackTag) {
+          removeBalancerLoopbackIfOrphaned(tt, oldTarget);
+        }
+        if (isFallbackABalancer) {
+          ensureBalancerLoopback(tt, form.fallbackTag);
         }
       }
       syncObservatories(tt);
@@ -185,6 +242,15 @@ export default function BalancersTab({
   }
 
   function confirmDelete(idx: number) {
+    const deletedTag = rows[idx]?.tag;
+    const lbTag = loopbackTagFor(deletedTag);
+    const dependents = (templateSettings?.routing?.balancers || [])
+      .filter((b) => b.tag !== deletedTag && b.fallbackTag === lbTag)
+      .map((b) => b.tag);
+    if (dependents.length > 0) {
+      messageApi.error(t('pages.xray.balancer.balancerDeleteInUse', { names: dependents.join(', ') }));
+      return;
+    }
     const removed = templateSettings
       ? observersRemovedByDeletingBalancer(templateSettings, idx)
       : { observatory: false, burst: false };
@@ -199,7 +265,14 @@ export default function BalancersTab({
       cancelText: t('cancel'),
       onOk: () => mutate((tt) => {
         if (tt.routing?.balancers) {
+          const deletedTag = tt.routing.balancers[idx]?.tag;
+          removeBalancerLoopback(tt, deletedTag);
           tt.routing.balancers.splice(idx, 1);
+          if (tt.routing?.rules) {
+            tt.routing.rules = tt.routing.rules.filter(
+              (r) => r?.balancerTag !== deletedTag,
+            );
+          }
           syncObservatories(tt);
         }
       }),
@@ -278,7 +351,7 @@ export default function BalancersTab({
           </Tag>
         )),
     },
-    { title: 'Fallback', dataIndex: 'fallbackTag', key: 'fallbackTag', align: 'center', width: 160 },
+    { title: 'Fallback', dataIndex: 'displayFallbackTag', key: 'displayFallbackTag', align: 'center', width: 160 },
     {
       title: t('pages.xray.balancerLive'),
       key: 'live',
@@ -293,9 +366,13 @@ export default function BalancersTab({
             </Tooltip>
           );
         }
-        const picked = live.override || live.selected?.[0] || record.fallbackTag;
+        const resolve = (tag: string) => isBalancerLoopbackTag(tag) ? resolveLoopbackFallback(templateSettings!, tag) : tag;
+        const picked = live.override ? resolve(live.override) : live.selected?.[0] ? resolve(live.selected[0]) : record.displayFallbackTag;
+        const tooltipText = live.override
+          ? resolve(live.override)
+          : (live.selected || []).map(resolve).join(', ');
         return (
-          <Tooltip title={(live.selected || []).join(', ') || undefined}>
+          <Tooltip title={tooltipText || undefined}>
             <Tag color={live.override ? 'orange' : 'blue'}>{picked || '—'}</Tag>
           </Tooltip>
         );
@@ -308,6 +385,23 @@ export default function BalancersTab({
       width: 200,
       render: (_v, record) => {
         const live = liveStatus[record.tag];
+        const resolvedFB = record.displayFallbackTag;
+        let options = overrideOptions;
+        if (resolvedFB && !outboundTags.includes(resolvedFB)) {
+          options = [...overrideOptions, {
+            value: resolvedFB,
+            label: (
+              <span>
+                <Tag color="blue" style={{ marginRight: 4 }}>{t('pages.xray.rules.balancer')}</Tag>
+                {resolvedFB}
+              </span>
+            ),
+          }];
+        }
+        const rawOverride = live?.override || undefined;
+        const resolvedOverride = rawOverride && isBalancerLoopbackTag(rawOverride)
+          ? resolveLoopbackFallback(templateSettings!, rawOverride)
+          : rawOverride;
         return (
           <Select
             size="small"
@@ -315,8 +409,8 @@ export default function BalancersTab({
             placeholder={t('pages.xray.balancerOverridePh')}
             allowClear
             disabled={!live?.running}
-            value={live?.override || undefined}
-            options={outboundTags.map((tag) => ({ label: tag, value: tag }))}
+            value={resolvedOverride}
+            options={options}
             onChange={(v) => setOverride(record.tag, (v as string | undefined) || '')}
           />
         );
@@ -359,6 +453,7 @@ export default function BalancersTab({
   return (
     <>
       {modalContextHolder}
+      {messageContextHolder}
       <Tabs
         items={[
           {
@@ -385,6 +480,9 @@ export default function BalancersTab({
         open={modalOpen}
         balancer={editingBalancer}
         outboundTags={outboundTags}
+        balancerTags={balancerTags}
+        balancers={balancerObjects}
+        templateSettings={templateSettings}
         otherTags={otherTags}
         onClose={() => setModalOpen(false)}
         onConfirm={onConfirm}

frontend/src/pages/xray/balancers/balancer-loopback.ts

@@ -0,0 +1,198 @@
+import type { XraySettingsValue } from '@/hooks/useXraySetting';
+
+const LOOPBACK_PREFIX = '_bl_';
+
+export function isBalancerLoopbackTag(tag: string): boolean {
+  return tag.startsWith(LOOPBACK_PREFIX);
+}
+
+export function loopbackTagFor(targetBalancerTag: string): string {
+  return LOOPBACK_PREFIX + targetBalancerTag;
+}
+
+export function balancerTagFromLoopback(loopbackTag: string): string | null {
+  if (!isBalancerLoopbackTag(loopbackTag)) return null;
+  return loopbackTag.slice(LOOPBACK_PREFIX.length);
+}
+
+function loopbackMatchesTarget(loopbackTag: string, targetTag: string): boolean {
+  if (!isBalancerLoopbackTag(loopbackTag)) return false;
+  const target = balancerTagFromLoopback(loopbackTag);
+  return target === targetTag;
+}
+
+function findLoopbackTarget(settings: XraySettingsValue, loopbackTag: string): string | null {
+  const rules = (settings.routing?.rules || []) as Array<{ inboundTag?: string[]; balancerTag?: string }>;
+  for (const r of rules) {
+    if (Array.isArray(r.inboundTag) && r.inboundTag.includes(loopbackTag) && r.balancerTag) {
+      return r.balancerTag;
+    }
+  }
+  return null;
+}
+
+export function resolveLoopbackFallback(
+  settings: XraySettingsValue,
+  fallbackTag: string,
+): string {
+  if (!fallbackTag || !isBalancerLoopbackTag(fallbackTag)) return fallbackTag;
+  const target = findLoopbackTarget(settings, fallbackTag);
+  if (target) return target;
+  const targetTag = balancerTagFromLoopback(fallbackTag);
+  return targetTag || fallbackTag;
+}
+
+function countLoopbackRefs(settings: XraySettingsValue, targetTag: string): number {
+  let count = 0;
+  for (const b of (settings.routing?.balancers || []) as Array<{ fallbackTag?: string }>) {
+    if (b.fallbackTag && isBalancerLoopbackTag(b.fallbackTag) && loopbackMatchesTarget(b.fallbackTag, targetTag)) {
+      count++;
+    }
+  }
+  return count;
+}
+
+export function ensureBalancerLoopback(
+  settings: XraySettingsValue,
+  targetBalancerTag: string,
+): void {
+  const lbTag = loopbackTagFor(targetBalancerTag);
+
+  if (!Array.isArray(settings.outbounds)) settings.outbounds = [];
+  const existingIdx = (settings.outbounds as Array<{ tag?: string; protocol?: string }>).findIndex(
+    (o) => o.tag === lbTag,
+  );
+  const newOutbound = { tag: lbTag, protocol: 'loopback', settings: { inboundTag: lbTag } };
+  if (existingIdx >= 0) {
+    (settings.outbounds as Record<string, unknown>[])[existingIdx] = newOutbound;
+  } else {
+    (settings.outbounds as Record<string, unknown>[]).push(newOutbound);
+  }
+
+  if (!settings.routing) settings.routing = { rules: [], balancers: [] };
+  if (!Array.isArray(settings.routing.rules)) settings.routing.rules = [];
+
+  const existingRuleIdx = (settings.routing.rules as Array<{ inboundTag?: string[] }>).findIndex(
+    (r) => Array.isArray(r.inboundTag) && r.inboundTag.includes(lbTag),
+  );
+  if (existingRuleIdx >= 0) {
+    (settings.routing.rules as Record<string, unknown>[])[existingRuleIdx].balancerTag = targetBalancerTag;
+  } else {
+    (settings.routing.rules as Record<string, unknown>[]).push({
+      type: 'field',
+      inboundTag: [lbTag],
+      balancerTag: targetBalancerTag,
+    });
+  }
+}
+
+export function removeBalancerLoopbackIfOrphaned(
+  settings: XraySettingsValue,
+  targetBalancerTag: string,
+): void {
+  if (countLoopbackRefs(settings, targetBalancerTag) > 0) return;
+  removeBalancerLoopback(settings, targetBalancerTag);
+}
+
+export function removeBalancerLoopback(
+  settings: XraySettingsValue,
+  targetBalancerTag: string,
+): void {
+  const lbTag = loopbackTagFor(targetBalancerTag);
+
+  if (Array.isArray(settings.outbounds)) {
+    settings.outbounds = (settings.outbounds as Array<{ tag?: string }>).filter(
+      (o) => o.tag !== lbTag,
+    ) as XraySettingsValue['outbounds'];
+  }
+
+  if (settings.routing && Array.isArray(settings.routing.rules)) {
+    settings.routing.rules = (settings.routing.rules as Array<{ inboundTag?: string[] }>).filter(
+      (r) => !(Array.isArray(r.inboundTag) && r.inboundTag.includes(lbTag)),
+    ) as XraySettingsValue['routing'] extends { rules?: infer R } ? R : never;
+  }
+}
+
+export function propagateBalancerTagRename(
+  settings: XraySettingsValue,
+  oldTag: string,
+  newTag: string,
+): void {
+  const oldLbTag = loopbackTagFor(oldTag);
+  const newLbTag = loopbackTagFor(newTag);
+
+  if (Array.isArray(settings.outbounds)) {
+    for (const o of settings.outbounds as Array<{ tag?: string; settings?: { inboundTag?: string } }>) {
+      if (o.tag === oldLbTag) o.tag = newLbTag;
+      if (o.settings?.inboundTag === oldLbTag) o.settings.inboundTag = newLbTag;
+    }
+  }
+
+  if (settings.routing && Array.isArray(settings.routing.rules)) {
+    for (const r of settings.routing.rules as Array<{ inboundTag?: string[] }>) {
+      if (Array.isArray(r.inboundTag)) {
+        const idx = r.inboundTag.indexOf(oldLbTag);
+        if (idx !== -1) r.inboundTag[idx] = newLbTag;
+      }
+    }
+  }
+
+  if (settings.routing && Array.isArray(settings.routing.balancers)) {
+    for (const b of settings.routing.balancers as Array<{ tag?: string; fallbackTag?: string }>) {
+      if (b.fallbackTag === oldLbTag) b.fallbackTag = newLbTag;
+    }
+  }
+}
+
+export function detectBalancerCycles(settings: XraySettingsValue): string[][] {
+  const balancers = (settings.routing?.balancers || []) as Array<{ tag?: string; fallbackTag?: string }>;
+  const cycles: string[][] = [];
+
+  for (const b of balancers) {
+    if (!b.tag || !b.fallbackTag || !isBalancerLoopbackTag(b.fallbackTag)) continue;
+    const targetTag = balancerTagFromLoopback(b.fallbackTag);
+    if (!targetTag) continue;
+
+    const visited = new Set<string>();
+    let cursor = targetTag;
+    while (cursor && !visited.has(cursor)) {
+      if (cursor === b.tag) {
+        cycles.push([b.tag, targetTag]);
+        break;
+      }
+      visited.add(cursor);
+      const next = balancers.find((x) => x.tag === cursor);
+      const fb = next?.fallbackTag;
+      if (!fb || !isBalancerLoopbackTag(fb)) break;
+      cursor = balancerTagFromLoopback(fb) || '';
+    }
+  }
+  return cycles;
+}
+
+export function ensureMissingBalancerLoopbacks(settings: XraySettingsValue): void {
+  const balancers = (settings.routing?.balancers || []) as Array<{ tag?: string; fallbackTag?: string }>;
+  for (const b of balancers) {
+    if (!b.fallbackTag || !isBalancerLoopbackTag(b.fallbackTag)) continue;
+    const targetTag = balancerTagFromLoopback(b.fallbackTag);
+    if (!targetTag) continue;
+    ensureBalancerLoopback(settings, targetTag);
+  }
+}
+
+export function cleanupOrphanedBalancerLoopbacks(settings: XraySettingsValue): void {
+  if (!Array.isArray(settings.outbounds)) return;
+
+  const orphanedTags: string[] = [];
+  for (const o of settings.outbounds as Array<{ tag?: string; protocol?: string }>) {
+    if (o.protocol !== 'loopback' || !o.tag || !isBalancerLoopbackTag(o.tag)) continue;
+    const targetTag = balancerTagFromLoopback(o.tag);
+    if (targetTag && countLoopbackRefs(settings, targetTag) === 0) {
+      orphanedTags.push(targetTag);
+    }
+  }
+
+  for (const tag of orphanedTags) {
+    removeBalancerLoopback(settings, tag);
+  }
+}

frontend/src/pages/xray/outbounds/OutboundFormModal.tsx

@@ -330,6 +330,10 @@ export default function OutboundFormModal({
       messageApi.error(t('pages.xray.outboundForm.tagRequired'));
       return;
     }
+    if (tagValue.startsWith('_bl_')) {
+      messageApi.error(t('pages.xray.balancer.reservedPrefix'));
+      return;
+    }
     const isDuplicateTag = (existingTags || []).includes(tagValue)
       && !(isEdit && (outboundProp?.tag as string | undefined) === tagValue);
     if (isDuplicateTag) {

frontend/src/pages/xray/outbounds/OutboundsTab.tsx

@@ -43,6 +43,7 @@ import TextModal from '@/components/feedback/TextModal';
 
 import OutboundFormModal from './OutboundFormModal';
 import { propagateOutboundTagRename } from '../basics/helpers';
+import { isBalancerLoopbackTag } from '../balancers/balancer-loopback';
 import type { XraySettingsValue, SetTemplate, OutboundTestState, OutboundTrafficRow } from '@/hooks/useXraySetting';
 import './OutboundsTab.css';
 
@@ -140,7 +141,13 @@ export default function OutboundsTab({
     [templateSettings?.outbounds],
   );
 
-  const rows = useMemo(() => outbounds.map((o, i) => ({ ...o, key: i })), [outbounds]);
+  const rows = useMemo(
+    () =>
+      outbounds
+        .map((o, i) => ({ ...o, key: i }))
+        .filter((o) => !isBalancerLoopbackTag(o.tag || '')),
+    [outbounds],
+  );
 
   const dialerProxyTags = useMemo(() => {
     const tags = new Set<string>();

frontend/src/pages/xray/routing/RoutingTab.tsx

@@ -14,6 +14,7 @@ import {
 import { catTabLabel } from '@/pages/settings/catTabLabel';
 import PromptModal from '@/components/feedback/PromptModal';
 import TextModal from '@/components/feedback/TextModal';
+import { isBalancerLoopbackTag } from '../balancers/balancer-loopback';
 import RoutingBasic from './RoutingBasic';
 import RouteTester from './RouteTester';
 import RuleFormModal from './RuleFormModal';
@@ -66,26 +67,31 @@ export default function RoutingTab({
 
   const rows: RuleRow[] = useMemo(
     () =>
-      rules.map((rule, idx) => {
-        const r: RuleRow = { key: idx };
-        r.enabled = rule.enabled !== false;
-        r.domain = arrJoin(rule.domain);
-        r.ip = arrJoin(rule.ip);
-        r.port = rule.port;
-        r.sourcePort = rule.sourcePort;
-        r.vlessRoute = rule.vlessRoute;
-        r.network = rule.network;
-        r.sourceIP = arrJoin(rule.sourceIP);
-        r.user = arrJoin(rule.user);
-        r.inboundTag = arrJoin(rule.inboundTag);
-        r.protocol = arrJoin(rule.protocol);
-        if (rule.attrs && typeof rule.attrs === 'object' && !Array.isArray(rule.attrs)) {
-          r.attrs = JSON.stringify(rule.attrs, null, 2);
-        }
-        r.outboundTag = rule.outboundTag;
-        r.balancerTag = rule.balancerTag;
-        return r;
-      }),
+      rules
+        .map((rule, idx) => {
+          const r: RuleRow = { key: idx };
+          r.enabled = rule.enabled !== false;
+          r.domain = arrJoin(rule.domain);
+          r.ip = arrJoin(rule.ip);
+          r.port = rule.port;
+          r.sourcePort = rule.sourcePort;
+          r.vlessRoute = rule.vlessRoute;
+          r.network = rule.network;
+          r.sourceIP = arrJoin(rule.sourceIP);
+          r.user = arrJoin(rule.user);
+          r.inboundTag = arrJoin(rule.inboundTag);
+          r.protocol = arrJoin(rule.protocol);
+          if (rule.attrs && typeof rule.attrs === 'object' && !Array.isArray(rule.attrs)) {
+            r.attrs = JSON.stringify(rule.attrs, null, 2);
+          }
+          r.outboundTag = rule.outboundTag;
+          r.balancerTag = rule.balancerTag;
+          return r;
+        })
+        .filter((r) => {
+          const inboundTags = (rules[r.key]?.inboundTag || []) as string[];
+          return !inboundTags.some(isBalancerLoopbackTag);
+        }),
     [rules],
   );
 
@@ -105,7 +111,7 @@ export default function RoutingTab({
     const seen = new Set<string>();
     const out: string[] = [];
     const push = (tag?: string) => {
-      if (!tag || seen.has(tag)) return;
+      if (!tag || seen.has(tag) || isBalancerLoopbackTag(tag)) return;
       seen.add(tag);
       out.push(tag);
     };

frontend/src/schemas/xray.ts

@@ -101,7 +101,10 @@ export const RuleFormSchema = z.object({
 });
 
 export const BalancerFormSchema = z.object({
-  tag: z.string().trim().min(1, 'pages.xray.balancerTagRequired'),
+  tag: z.string().trim().min(1, 'pages.xray.balancerTagRequired').refine(
+    (val) => !val.startsWith('_bl_'),
+    { message: 'pages.xray.balancer.reservedPrefix' },
+  ),
   strategy: BalancerStrategyTypeSchema.default('random'),
   selector: z.array(z.string()).min(1, 'pages.xray.balancerSelectorRequired'),
   fallbackTag: z.string().default(''),
@@ -111,7 +114,11 @@ export const BalancerFormSchema = z.object({
 export const OutboundTagSchema = z
   .string()
   .trim()
-  .min(1, 'pages.xray.outboundTagRequired');
+  .min(1, 'pages.xray.outboundTagRequired')
+  .refine(
+    (val) => !val.startsWith('_bl_'),
+    { message: 'pages.xray.balancer.reservedPrefix' },
+  );
 
 export type BalancerFormValues = z.infer<typeof BalancerFormSchema>;
 export type RuleFormValues = z.infer<typeof RuleFormSchema>;

frontend/src/test/balancer-form-modal.test.tsx

@@ -10,6 +10,9 @@ function renderModal(onConfirm = vi.fn()) {
       open
       balancer={null}
       outboundTags={['proxy', 'direct']}
+      balancerTags={[]}
+      balancers={[]}
+      templateSettings={null}
       otherTags={['existing']}
       onClose={() => {}}
       onConfirm={onConfirm}

internal/web/service/xray.go

@@ -906,11 +906,23 @@ func (s *XrayService) GetBalancersStatus(tags []string) ([]BalancerStatus, error
 }
 
 // OverrideBalancer forces a balancer in the running core to use the given
-// outbound tag; an empty target clears the override.
+// outbound tag; an empty target clears the override. When target names
+// another balancer, the override resolves to the loopback outbound that
+// routes traffic through the target balancer via the routing rules.
 func (s *XrayService) OverrideBalancer(tag, target string) error {
 	if !s.IsXrayRunning() {
 		return errors.New("xray is not running")
 	}
+	if target != "" {
+		resolved, err := s.resolveOverrideTarget(target)
+		if err != nil {
+			return err
+		}
+		if resolved == "" {
+			return errors.New("balancer fallback target not found in routing rules")
+		}
+		target = resolved
+	}
 	if err := s.xrayAPI.Init(p.GetAPIPort()); err != nil {
 		return err
 	}
@@ -918,6 +930,42 @@ func (s *XrayService) OverrideBalancer(tag, target string) error {
 	return s.xrayAPI.SetBalancerTarget(tag, target)
 }
 
+// resolveOverrideTarget checks if target names a balancer and, if so,
+// returns the loopback outbound tag that routes to it through the
+// routing rules. Returns empty if target is already a concrete outbound.
+func (s *XrayService) resolveOverrideTarget(target string) (string, error) {
+	template, err := s.settingService.GetXrayConfigTemplate()
+	if err != nil {
+		return "", err
+	}
+	var cfg map[string]any
+	if err := json.Unmarshal([]byte(template), &cfg); err != nil {
+		return "", err
+	}
+	routing, _ := cfg["routing"].(map[string]any)
+	if routing == nil {
+		return "", nil
+	}
+	rules, _ := routing["rules"].([]any)
+	for _, r := range rules {
+		rule, ok := r.(map[string]any)
+		if !ok {
+			continue
+		}
+		if rule["balancerTag"] != target {
+			continue
+		}
+		inboundTags, ok := rule["inboundTag"].([]any)
+		if !ok || len(inboundTags) == 0 {
+			continue
+		}
+		if lbTag, ok := inboundTags[0].(string); ok && strings.HasPrefix(lbTag, "_bl_") {
+			return lbTag, nil
+		}
+	}
+	return "", nil
+}
+
 // TestRoute asks the running core which outbound its router picks for the
 // described connection.
 func (s *XrayService) TestRoute(req xray.RouteTestRequest) (*xray.RouteTestResult, error) {

internal/web/translation/ar-EG.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "وسم موازن فريد",
         "selector": "المحدد",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "اختر موزان أحمال آخر كبديل",
+        "balancerFallbackInfo": "سيتم توجيه حركة المرور عبر: الموزان → Loopback → الخادم → الموزان المستهدف → الاتصال الخارجي. سيؤدي هذا إلى إضافة قفزة إضافية عبر الخادم، مما قد يسبب تأخيرات طفيفة.",
+        "balancerFallbackCycle": "لا يمكن تعيين هذا الموزان كبديل — سيؤدي ذلك إلى إنشاء تبعية دائرية.",
+        "balancerDeleteInUse": "لا يمكن حذف هذا الموزان — يتم استخدامه كبديل لـ: {names}",
         "expected": "المتوقع",
         "expectedPlaceholder": "العدد الأمثل للعقد",
         "maxRtt": "أقصى RTT",
         "tolerance": "التحمل",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "ماينفعش تستخدم balancerTag و outboundTag مع بعض. لو اتستخدموا مع بعض، outboundTag هو اللي هيشتغل."
+        "balancerDesc": "ماينفعش تستخدم balancerTag و outboundTag مع بعض. لو اتستخدموا مع بعض، outboundTag هو اللي هيشتغل.",
+        "cycleTooltip": "حلقة: {path} → (العودة إلى {start})"
       },
       "wireguard": {
         "secretKey": "المفتاح السري",
@@ -2152,4 +2157,4 @@
     "statusDown": "غير متصل",
     "statusUp": "متصل"
   }
-}
+}

internal/web/translation/en-US.json

@@ -1825,6 +1825,12 @@
         "tagPlaceholder": "unique balancer tag",
         "selector": "Selector",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Select another balancer as fallback",
+        "balancerFallbackInfo": "Traffic will be routed through: Balancer → Loopback → Server → Target Balancer → Outbound. This adds an extra hop through the server, which may introduce slight delays.",
+        "balancerFallbackCycle": "Cannot set this balancer as fallback — it would create a circular dependency.",
+        "balancerDeleteInUse": "Cannot delete this balancer — it is used as fallback by: {names}",
+        "reservedPrefix": "_bl_ prefix is reserved for internal balancer loopback objects",
+        "cycleTooltip": "Cycle: {path} → (back to {start})",
         "expected": "Expected",
         "expectedPlaceholder": "optimal node count",
         "maxRtt": "Max RTT",
@@ -2155,4 +2161,4 @@
     "statusDown": "DOWN",
     "statusUp": "UP"
   }
-}
+}

internal/web/translation/es-ES.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "etiqueta única de balanceador",
         "selector": "Selector",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Seleccione otro balanceador como respaldo",
+        "balancerFallbackInfo": "El tráfico se enrutará a través de: Balanceador → Loopback → Servidor → Balanceador destino → Conexión saliente. Esto agrega un salto adicional a través del servidor, lo que puede introducir ligeros retrasos.",
+        "balancerFallbackCycle": "No se puede establecer este balanceador como respaldo — crearía una dependencia circular.",
+        "balancerDeleteInUse": "No se puede eliminar este balanceador — se usa como respaldo para: {names}",
         "expected": "Esperado",
         "expectedPlaceholder": "número óptimo de nodos",
         "maxRtt": "Máx. RTT",
         "tolerance": "Tolerancia",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "No es posible utilizar balancerTag y outboundTag al mismo tiempo. Si se utilizan al mismo tiempo, sólo funcionará outboundTag."
+        "balancerDesc": "No es posible utilizar balancerTag y outboundTag al mismo tiempo. Si se utilizan al mismo tiempo, sólo funcionará outboundTag.",
+        "cycleTooltip": "Ciclo: {path} → (volver a {start})"
       },
       "wireguard": {
         "secretKey": "Llave secreta",
@@ -2152,4 +2157,4 @@
     "statusDown": "CAÍDO",
     "statusUp": "ACTIVO"
   }
-}
+}

internal/web/translation/fa-IR.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "تگ منحصربه‌فرد بالانسر",
         "selector": "انتخابگر",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "یک بالانسر دیگر به عنوان پشتیبان انتخاب کنید",
+        "balancerFallbackInfo": "ترافیک از مسیر زیر مسیریابی می‌شود: بالانسر → Loopback → سرور → بالانسر مقصد → اتصال خروجی. این یک پرش اضافی از طریق سرور اضافه می‌کند که ممکن است تأخیرهای جزئی ایجاد کند.",
+        "balancerFallbackCycle": "امکان تنظیم این بالانسر به عنوان پشتیبان وجود ندارد — وابستگی دایره‌ای ایجاد می‌کند.",
+        "balancerDeleteInUse": "امکان حذف این بالانسر وجود ندارد — به عنوان پشتیبان برای موارد زیر استفاده می‌شود: {names}",
         "expected": "مورد انتظار",
         "expectedPlaceholder": "تعداد نود بهینه",
         "maxRtt": "حداکثر RTT",
         "tolerance": "تحمل",
         "baselines": "خطوط پایه",
         "costs": "هزینه‌ها",
-        "balancerDesc": "امکان استفاده همزمان balancerTag و outboundTag باهم وجود ندارد. درصورت استفاده همزمان فقط outboundTag عمل خواهد کرد."
+        "balancerDesc": "امکان استفاده همزمان balancerTag و outboundTag باهم وجود ندارد. درصورت استفاده همزمان فقط outboundTag عمل خواهد کرد.",
+        "cycleTooltip": "حلقه: {path} → (بازگشت به {start})"
       },
       "wireguard": {
         "secretKey": "کلید شخصی",
@@ -2152,4 +2157,4 @@
     "statusDown": "قطع",
     "statusUp": "وصل"
   }
-}
+}

internal/web/translation/id-ID.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "tag balancer unik",
         "selector": "Selector",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Pilih load balancer lain sebagai fallback",
+        "balancerFallbackInfo": "Lalu lintas akan di-routing melalui: Load Balancer → Loopback → Server → Load Balancer tujuan → Koneksi keluar. Ini menambahkan hop tambahan melalui server, yang dapat menyebabkan sedikit penundaan.",
+        "balancerFallbackCycle": "Tidak dapat mengatur load balancer ini sebagai fallback — akan menciptakan dependensi siklik.",
+        "balancerDeleteInUse": "Tidak dapat menghapus load balancer ini — digunakan sebagai fallback untuk: {names}",
         "expected": "Diharapkan",
         "expectedPlaceholder": "jumlah node optimal",
         "maxRtt": "Maks. RTT",
         "tolerance": "Toleransi",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "BalancerTag dan outboundTag tidak dapat digunakan secara bersamaan. Jika digunakan secara bersamaan, hanya outboundTag yang akan berfungsi."
+        "balancerDesc": "BalancerTag dan outboundTag tidak dapat digunakan secara bersamaan. Jika digunakan secara bersamaan, hanya outboundTag yang akan berfungsi.",
+        "cycleTooltip": "Siklus: {path} → (kembali ke {start})"
       },
       "wireguard": {
         "secretKey": "Kunci Rahasia",
@@ -2152,4 +2157,4 @@
     "statusDown": "MATI",
     "statusUp": "AKTIF"
   }
-}
+}

internal/web/translation/ja-JP.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "一意のバランサータグ",
         "selector": "セレクター",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "フォールバックとして別のバランサーを選択してください",
+        "balancerFallbackInfo": "トラフィックは以下のルートで転送されます：バランサー → Loopback → サーバー → ターゲットバランサー → アウトバウンド。これによりサーバーを経由する追加ホップが発生し、多少の遅延が生じる場合があります。",
+        "balancerFallbackCycle": "このバランサーをフォールバックに設定できません — 循環依存が発生します。",
+        "balancerDeleteInUse": "このバランサーを削除できません — 以下のバランサーのフォールバックとして使用されています：{names}",
         "expected": "期待値",
         "expectedPlaceholder": "最適ノード数",
         "maxRtt": "最大 RTT",
         "tolerance": "許容範囲",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "balancerTagとoutboundTagは同時に使用できません。同時に使用された場合、outboundTagのみが有効になります。"
+        "balancerDesc": "balancerTagとoutboundTagは同時に使用できません。同時に使用された場合、outboundTagのみが有効になります。",
+        "cycleTooltip": "循環: {path} → ({start} に戻る)"
       },
       "wireguard": {
         "secretKey": "シークレットキー",
@@ -2152,4 +2157,4 @@
     "statusDown": "ダウン",
     "statusUp": "アップ"
   }
-}
+}

internal/web/translation/pt-BR.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "tag única do balanceador",
         "selector": "Seletor",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Selecione outro balanceador como fallback",
+        "balancerFallbackInfo": "O tráfego será roteado através de: Balanceador → Loopback → Servidor → Balanceador de destino → Conexão de saída. Isso adiciona um salto extra pelo servidor, o que pode introduzir pequenos atrasos.",
+        "balancerFallbackCycle": "Não é possível definir este balanceador como fallback — isso criaria uma dependência circular.",
+        "balancerDeleteInUse": "Não é possível excluir este balanceador — ele é usado como fallback para: {names}",
         "expected": "Esperado",
         "expectedPlaceholder": "número ótimo de nós",
         "maxRtt": "Máx. RTT",
         "tolerance": "Tolerância",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "Não é possível usar balancerTag e outboundTag ao mesmo tempo. Se usados simultaneamente, apenas outboundTag funcionará."
+        "balancerDesc": "Não é possível usar balancerTag e outboundTag ao mesmo tempo. Se usados simultaneamente, apenas outboundTag funcionará.",
+        "cycleTooltip": "Ciclo: {path} → (voltar para {start})"
       },
       "wireguard": {
         "secretKey": "Chave Secreta",
@@ -2152,4 +2157,4 @@
     "statusDown": "INATIVO",
     "statusUp": "ATIVO"
   }
-}
+}

internal/web/translation/ru-RU.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "уникальный тег балансировщика",
         "selector": "Селектор",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Выберите другой балансировщик в качестве запасного",
+        "balancerFallbackInfo": "Трафик будет маршрутизирован через: Балансировщик → Loopback → Сервер → Целевой балансировщик → Исходящее соединение. Это добавляет дополнительный хоп через сервер, что может вызвать небольшие задержки.",
+        "balancerFallbackCycle": "Невозможно назначить этот балансировщик запасным — это создаст циклическую зависимость.",
+        "balancerDeleteInUse": "Невозможно удалить этот балансировщик — он используется как запасной для: {names}",
         "expected": "Ожидаемое",
         "expectedPlaceholder": "оптимальное число узлов",
         "maxRtt": "Макс. RTT",
         "tolerance": "Допуск",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "Невозможно одновременно использовать balancerTag и outboundTag. При одновременном использовании будет работать только outboundTag."
+        "balancerDesc": "Невозможно одновременно использовать balancerTag и outboundTag. При одновременном использовании будет работать только outboundTag.",
+        "cycleTooltip": "Цикл: {path} → (обратно к {start})"
       },
       "wireguard": {
         "secretKey": "Секретный ключ",
@@ -2152,4 +2157,4 @@
     "statusDown": "НЕДОСТУПЕН",
     "statusUp": "РАБОТАЕТ"
   }
-}
+}

internal/web/translation/tr-TR.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "benzersiz dengeleyici etiketi",
         "selector": "Seçici",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Yedek olarak başka bir dengeleyici seçin",
+        "balancerFallbackInfo": "Trafik şu yoldan yönlendirilecektir: Dengeleyici → Loopback → Sunucu → Hedef dengeleyici → Bağlantı çıkışı. Bu, sunucu üzerinden ek bir atlama ekler ve hafif gecikmelere neden olabilir.",
+        "balancerFallbackCycle": "Bu dengeleyiciyi yedek olarak ayarlayamazsınız — döngüsel bağımlılık oluşturur.",
+        "balancerDeleteInUse": "Bu dengeleyici silinemez — şu dengeleyicilerin yedeği olarak kullanılmaktadır: {names}",
         "expected": "Beklenen",
         "expectedPlaceholder": "optimal düğüm sayısı",
         "maxRtt": "Maks. RTT",
         "tolerance": "Tolerans",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "Dengeleyici Etiketi (balancerTag) ve Giden Bağlantı Etiketi (outboundTag) aynı anda kullanılamaz. Aynı anda kullanıldığında yalnızca giden bağlantı etiketi geçerli olur."
+        "balancerDesc": "Dengeleyici Etiketi (balancerTag) ve Giden Bağlantı Etiketi (outboundTag) aynı anda kullanılamaz. Aynı anda kullanıldığında yalnızca giden bağlantı etiketi geçerli olur.",
+        "cycleTooltip": "Döngü: {path} → ({start} adresine geri dön)"
       },
       "wireguard": {
         "secretKey": "Gizli Anahtar",
@@ -2152,4 +2157,4 @@
     "statusDown": "ÇEVRİMDIŞI",
     "statusUp": "ÇEVRİMİÇİ"
   }
-}
+}

internal/web/translation/uk-UA.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "унікальний тег балансувальника",
         "selector": "Селектор",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Оберіть інший балансувач як резервний",
+        "balancerFallbackInfo": "Трафік буде маршрутизовано через: Балансувач → Loopback → Сервер → Цільовий балансувач → Вихідне зʼєднання. Це додає додатковий хоп через сервер, що може спричинити невеликі затримки.",
+        "balancerFallbackCycle": "Неможливо призначити цей балансувач резервним — це створить циклічну залежність.",
+        "balancerDeleteInUse": "Неможливо видалити цей балансувач — він використовується як резервний для: {names}",
         "expected": "Очікуване",
         "expectedPlaceholder": "оптимальна кількість вузлів",
         "maxRtt": "Макс. RTT",
         "tolerance": "Допуск",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "Неможливо використовувати balancerTag і outboundTag одночасно. Якщо використовувати одночасно, працюватиме лише outboundTag."
+        "balancerDesc": "Неможливо використовувати balancerTag і outboundTag одночасно. Якщо використовувати одночасно, працюватиме лише outboundTag.",
+        "cycleTooltip": "Цикл: {path} → (назад до {start})"
       },
       "wireguard": {
         "secretKey": "Приватний ключ",
@@ -2152,4 +2157,4 @@
     "statusDown": "НЕДОСТУПНО",
     "statusUp": "ДОСТУПНО"
   }
-}
+}

internal/web/translation/vi-VN.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "tag balancer duy nhất",
         "selector": "Selector",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "Chọn một load balancer khác làm dự phòng",
+        "balancerFallbackInfo": "Lưu lượng sẽ được định tuyến qua: Load Balancer → Loopback → Máy chủ → Load Balancer mục tiêu → kết nối ra ngoài. Điều này thêm một hop bổ sung qua máy chủ, có thể gây ra độ trễ nhẹ.",
+        "balancerFallbackCycle": "Không thể đặt load balancer này làm dự phòng — sẽ tạo ra phụ thuộc vòng.",
+        "balancerDeleteInUse": "Không thể xóa load balancer này — nó được sử dụng làm dự phòng cho: {names}",
         "expected": "Kỳ vọng",
         "expectedPlaceholder": "số node tối ưu",
         "maxRtt": "RTT tối đa",
         "tolerance": "Dung sai",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "Không thể sử dụng balancerTag và outboundTag cùng một lúc. Nếu sử dụng cùng lúc thì chỉ outboundTag mới hoạt động."
+        "balancerDesc": "Không thể sử dụng balancerTag và outboundTag cùng một lúc. Nếu sử dụng cùng lúc thì chỉ outboundTag mới hoạt động.",
+        "cycleTooltip": "Vòng lặp: {path} → (quay lại {start})"
       },
       "wireguard": {
         "secretKey": "Khoá bí mật",
@@ -2152,4 +2157,4 @@
     "statusDown": "NGỪNG HOẠT ĐỘNG",
     "statusUp": "HOẠT ĐỘNG"
   }
-}
+}

internal/web/translation/zh-CN.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "唯一均衡器标签",
         "selector": "选择器",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "选择另一个负载均衡器作为备用",
+        "balancerFallbackInfo": "流量将通过以下路径路由：负载均衡器 → Loopback → 服务器 → 目标负载均衡器 → 出站连接。这会增加一个经过服务器的额外跳转，可能会引入轻微延迟。",
+        "balancerFallbackCycle": "无法将此负载均衡器设置为备用 — 这会创建循环依赖。",
+        "balancerDeleteInUse": "无法删除此负载均衡器 — 它被用作以下负载均衡器的备用：{names}",
         "expected": "期望",
         "expectedPlaceholder": "最佳节点数",
         "maxRtt": "最大 RTT",
         "tolerance": "容差",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "无法同时使用 balancerTag 和 outboundTag。如果同时使用，则只有 outboundTag 会生效。"
+        "balancerDesc": "无法同时使用 balancerTag 和 outboundTag。如果同时使用，则只有 outboundTag 会生效。",
+        "cycleTooltip": "循环: {path} → (回到 {start})"
       },
       "wireguard": {
         "secretKey": "密钥",
@@ -2152,4 +2157,4 @@
     "statusDown": "断开",
     "statusUp": "恢复"
   }
-}
+}

internal/web/translation/zh-TW.json

@@ -1706,13 +1706,18 @@
         "tagPlaceholder": "唯一均衡器標籤",
         "selector": "選擇器",
         "fallback": "Fallback",
+        "fallbackBalancerHint": "選擇另一個負載平衡器作為備用",
+        "balancerFallbackInfo": "流量將透過以下路徑路由：負載平衡器 → Loopback → 伺服器 → 目標負載平衡器 → 出站連線。這會增加一個經過伺服器的額外跳轉，可能會引入輕微延遲。",
+        "balancerFallbackCycle": "無法將此負載平衡器設定為備用 — 這會建立循環依賴。",
+        "balancerDeleteInUse": "無法刪除此負載平衡器 — 它被用作以下負載平衡器的備用：{names}",
         "expected": "期望",
         "expectedPlaceholder": "最佳節點數",
         "maxRtt": "最大 RTT",
         "tolerance": "容差",
         "baselines": "Baselines",
         "costs": "Costs",
-        "balancerDesc": "無法同時使用 balancerTag 和 outboundTag。如果同時使用，則只有 outboundTag 會生效。"
+        "balancerDesc": "無法同時使用 balancerTag 和 outboundTag。如果同時使用，則只有 outboundTag 會生效。",
+        "cycleTooltip": "循環: {path} → (回到 {start})"
       },
       "wireguard": {
         "secretKey": "金鑰",
@@ -2152,4 +2157,4 @@
     "statusDown": "中斷",
     "statusUp": "恢復"
   }
-}
+}