查看“︁Photonicat 2 多出口与故障切换”︁的源代码

{| class="wikitable"
|-
! 适用 / Applies to
| Photonicat 2, photonicatWrt 26.04.x + pcat-manager-web 2026-06 及以后版本 / Photonicat 2, photonicatWrt 26.04.x with pcat-manager-web builds from 2026-06 onward
|}

Photonicat 2 同时拥有'''有线 WAN、WiFi 中继（Smart WAN）和 4G/5G 蜂窝'''三类出口。本页解释它们如何排定优先级、断线时如何自动切换、仪表盘指示灯的含义，以及排障方法。

The photonicat 2 has three egress classes at once: '''wired WAN, WiFi relay (Smart WAN), and 4G/5G cellular'''. This page explains how they're prioritized, how failover works, what the dashboard indicators mean, and how to debug it.

== 中文说明 ==

=== 优先级：路由 metric 链 ===
故障切换完全由'''路由 metric'''（数值越小优先级越高）决定——所有出口可以同时在线，流量始终走 metric 最小的可用出口：

{| class="wikitable"
! 出口 !! 接口 !! metric !! 说明
|-
| 有线宽带 || wan (eth0 / pppoe-wan) || '''1'''（IPv6 别名 wan_6 随主接口） || 最高优先级
|-
| WiFi 中继 (Smart WAN) || wan_wifi / wan_wifi_v6 || '''5 / 6''' || 次优先
|-
| 5G 蜂窝 || wwan_5g / wwan_5g_v6 || '''10 / 11''' || 兜底
|-
| LTE 蜂窝 || wwan_lte / wwan_lte_v6 || '''12 / 13''' || 兜底（LTE 模组）
|}

* '''插上网线''' → 有线立即接管（metric 1 最小）。
* '''拔掉网线''' → 有线路由消失，流量自动落到 WiFi 中继；WiFi 也没有 → 蜂窝。全程无需人工干预。
* '''WiFi 连上了但没有互联网'''（如未登录的酒店门户）：Smart WAN 的联网探测会把 wan_wifi 的 metric '''临时调到蜂窝之后'''——上网流量走蜂窝，WiFi 链路保持连接供你登录；探测恢复后自动还原。详见 [[Photonicat 2 Smart WAN 智能上网]]。

=== 与 pcat-manager 的关系 ===
固件自带的 pcat-manager 默认只跟踪有线 wan（eth0）：有线一断，pcat-manager 的策略会自动开启蜂窝网络，'''跳过 WiFi 中继'''，破坏上面的 metric 切换链。因此启用 Smart WAN 时，管理程序会自动把 pcat-manager 的规则切换为系统默认；关闭 Smart WAN 时自动还原。

=== 仪表盘指示 ===
* 首页拓扑图'''只点亮当前真正承载流量的出口'''（而不是"接口在线"）——有线/WiFi 中继/蜂窝一目了然。
* 同时显示 WiFi 信号强度与当前网络模式；多出口在线时 WAN 图标为组合图标。
* LAN 绿点只在存在可用出口时点亮。

=== 排障 ===
<pre>
ip route show default          # IPv4 默认路由及 metric（可能有多条，走 metric 最小者）
ip -6 route show default       # IPv6 同理
ip route get 1.1.1.1           # 当前实际选择的出口
ifstatus wan_wifi | head       # Smart WAN 接口状态
logread | grep -i wifi_wan     # Smart WAN 巡检/切换日志
</pre>
* 流量走了蜂窝但 WiFi 明明在线 → 查 <code>ip route show default</code>：若 wan_wifi 的 metric 被调高，说明门户探测判定该 WiFi 无法上网。
* 切换后个别应用卡住 → 长连接（VPN、SSH）绑定旧出口地址是正常现象，重连即可。

== English ==

=== Priority: the route-metric chain ===
Failover is driven purely by '''route metrics''' (lower wins). All uplinks can be up simultaneously; traffic always takes the lowest-metric available route:

{| class="wikitable"
! Egress !! Interface !! Metric !! Role
|-
| Wired broadband || wan (eth0 / pppoe-wan) || '''1''' (IPv6 alias wan_6 follows) || top priority
|-
| WiFi relay (Smart WAN) || wan_wifi / wan_wifi_v6 || '''5 / 6''' || second
|-
| 5G cellular || wwan_5g / wwan_5g_v6 || '''10 / 11''' || fallback
|-
| LTE cellular || wwan_lte / wwan_lte_v6 || '''12 / 13''' || fallback (LTE modems)
|}

* '''Plug in ethernet''' → wired takes over instantly (metric 1).
* '''Unplug it''' → the wired route vanishes; traffic falls to WiFi relay, then to cellular if no saved WiFi is reachable. No manual action.
* '''WiFi associated but no internet''' (e.g. an unauthenticated hotel portal): Smart WAN's connectivity probe '''temporarily demotes''' wan_wifi below cellular — internet traffic uses cellular while the WiFi stays associated for you to log in; the metric is restored on recovery. See [[Photonicat 2 Smart WAN 智能上网|Smart WAN]].

=== Interaction with pcat-manager ===
Stock pcat-manager only tracks the wired wan (eth0): when it drops, pcat-manager policies would enable cellular network, '''skipping WiFi relay''' and defeating the metric chain. So while Smart WAN is enabled, the manager automatically switches pcat-manager rules to default routing rule and restores them when Smart WAN is turned off.

=== Dashboard indicators ===
* The topology lights '''only the egress actually carrying traffic''' (not merely "interface up") — wired / WiFi relay / cellular at a glance.
* WiFi signal strength and the current network mode are shown; WAN icons composite when several uplinks are up.
* The LAN green dot requires a live egress.

=== Debugging ===
<pre>
ip route show default          # IPv4 default routes and metrics (lowest wins)
ip -6 route show default       # same for IPv6
ip route get 1.1.1.1           # which egress is actually selected right now
ifstatus wan_wifi | head       # Smart WAN interface state
logread | grep -i wifi_wan     # Smart WAN reconcile/failover logs
</pre>
* Traffic on cellular while WiFi looks fine → check <code>ip route show default</code>: a raised wan_wifi metric means the portal probe judged that WiFi offline.
* An app hangs right after failover → long-lived connections (VPN, SSH) pinned to the old egress address must reconnect; that's expected.

[[Photonicat 2 Smart WAN 智能上网]] ｜ [[Photonicat 4G/5G 家庭网络备份]] ｜ [[Photoincat 2 IPv6 PPPoE]]