Both Routers Were Faulty, and the Power Socket Explained Why (NBN 250M, Kingsford)

两台路由器都有问题，而原因藏在墙上的插座里（NBN 250兆，Kingsford）

House · KingsfordHouse · KingsfordNBN box · PPPoENBN box · PPPoE拨号250 Mbps plan250兆套餐2 identical ASUS routers两台同型号华硕19V 1.75A power draw电源规格19V 1.75ALoose wall socket墙上插座松动

When one router misbehaves you replace the router. When two identical routers in the same house both misbehave in different ways, the answer is usually not sitting inside either of them. This one took longer than most because there were several variables in play at once, and the thing that tied them together was a loose power socket.

一台路由器不正常，那就换路由器。同一栋房子里两台同型号的路由器、以不同方式都不正常，那答案通常不在这两台设备里面。这一单比一般的耗时，因为同时涉及的变量比较多，而把它们串起来的，是一个松动的墙插座。

The situation

基本情况

Location: Kingsford. Connection: NBN box with PPPoE dial-up. Plan: 250 Mbps.
Two ASUS routers of the same model, meshed together.
Reported fault: frequent dropouts, showing up mainly when several devices were connected at once.
Handled as an on-site visit. This case had more variables in play than most.

所在区域：Kingsford。接入方式：NBN box，PPPoE拨号。套餐：250兆。
家里有两台同型号的华硕路由器组网。
反馈的故障：频繁断网，主要出现在多设备同时连接的时候。
处理方式：线下上门。这个case涉及的变量比一般的多。

Diagnosing two routers, one at a time

两台路由器，一台一台查

Working through it on site现场排查顺序

Map the home network first先了解家庭网络架构

Two ASUS routers meshed两台华硕组网

Power down the second router to remove interference把副路由断电，排除干扰

Diagnose the main unit alone先单独诊断主路由

Main router: remove a stray cable in a LAN port主路由：拔掉LAN口上多接的一根线

Other end unknown另一端去向不明

Main router: try splitting the WiFi bands主路由：尝试拆分WiFi频段

Admin says saved, 5G light never lights后台提示成功，5G灯不亮

Second router: wired to a laptop via LAN副路由：用网线直连电脑

Port recognition drops in and out网口识别时有时无

Notice the socket: plugging in dips the NBN box发现插座问题：插拔会让旁边NBN设备短暂断电

Loose socket插座松动

Fit a TP-Link router and hand back for observation换上带的TP-Link路由器，交由客户观察使用

No further multi-device dropouts reported未再反馈多设备断网

The order here is deliberate: the second router was powered down before the main one was examined.

With two meshed units live, anything you observe on one can be caused by the other. Removing one from the picture is what makes the results readable.
On the main router, a LAN port had an extra cable in it whose other end could not be traced, so it was removed.
Splitting the WiFi bands was accepted in the admin page — the interface reported success — but the hardware never applied it and the 5G indicator did not come on. That is a router-side fault, not a settings mistake.
On the second router, connecting a computer directly to a LAN port produced repeated cycles of the port being recognised and then not, although its wireless side worked and could be configured.

这个顺序是刻意的：在检查主路由之前，先把副路由断电。

两台组网设备同时在线时，你在其中一台上看到的任何现象，都可能是另一台造成的。把一台移出画面，结果才读得懂。
主路由上，有个LAN口多接了一根网线，另一端连接未知，现场做了移除。
尝试拆分WiFi频段时，后台提示修改成功——界面说成功了——但硬件层面并未生效，5G的WiFi指示灯没有亮。这是路由器本身的问题，不是设置错了。
副路由上，用网线直连电脑，出现周期性的网口识别、又识别不到，尽管它的无线部分工作正常、也可以配置。

What tied the two faults together

把两个故障串起来的是什么

The power path, and what it was doing to the gear供电这条链路，对设备做了什么

Loose wall socket松动的墙插座

unstable / 不稳定

Bottleneck瓶颈

→

Router PSU 19V 1.75A路由器电源 19V 1.75A

high draw / 功率偏高

→

NBN box beside it旁边的NBN设备

briefly cut / 短暂断电

→

Both ASUS routers两台华硕路由器

faults in both / 均出现故障

The give-away was physical, not in any admin page: plugging the router's power into that socket briefly cut power to the NBN box next to it. Combined with the household's earlier report that a lightning event had already destroyed an NBN device, an unstable supply is the most consistent explanation for two matching routers failing in two different ways.真正的线索是物理层面的，不在任何后台页面里：把路由器电源插到那个插座上，会让旁边的NBN设备短暂断电。再结合客户此前反馈家里的NBN设备曾因打雷故障、后来更换过设备，供电不稳是对「两台同型号路由器以两种不同方式出故障」最一致的解释。

Apartments vs houses

公寓与House的差别

Why this bites houses more than apartments为什么House比公寓更容易遇到这个问题

	Apartment公寓	House独立屋 House
Supply stability供电稳定性	Generally more stable通常更稳定	More variable波动更大
High-draw routers高功率路由器	Less exposed受影响较小	More exposed — this pair ran at 19V 1.75A更容易受影响——本例是19V 1.75A
Typical symptom典型症状	——	Intermittent faults that move between devices间歇性故障，而且会在设备之间转移
What to do该做什么	——	Have the electrical side checked, not just the network请人检查电路，而不只是查网络

Two details from this job are worth carrying into your own setup.

The routers in use here are a high-end series with a lot of features, running at 19V 1.75A — a noticeably higher draw than an ordinary router. Higher-draw gear is more exposed to an unstable supply.
The household had already lost an NBN device to a lightning event and had it replaced, which fits the same picture rather than being a separate story.
We fitted a TP-Link router from the van and asked the client to use it for a while and report back. No further multi-device dropouts were reported.
We also recommended getting the electrical side of the house looked at promptly. Replacing networking gear does not fix a socket.

这一单有两个细节值得带回你自己的环境。

这里在用的是高端系列路由器，功能丰富，电源规格19V 1.75A——明显高于常规路由器的功率。功率越高的设备，越容易受供电不稳影响。
客户此前家里的NBN设备就因为打雷出现故障、后来更换过设备，这和同一个判断是吻合的，而不是另一件独立的事。
我们用带的TP-Link路由器接上，让客户先观察使用一段时间。之后未再反馈多设备连接断网的情况。
同时建议客户尽早找人对家里的电源风险做一次排查。换网络设备修不好一个插座。

Result最终结果

Assessment: both ASUS routers showed faults — the main unit would not apply a WiFi band split at hardware level despite the admin page reporting success, and the second unit's LAN port cycled in and out of recognition. The common factor was the power side: the socket the router plugged into was loose, and plugging it in briefly cut power to the NBN box next to it, in a household that had already lost an NBN device to a lightning event. These are high-draw units at 19V 1.75A. A TP-Link router was fitted and used for an observation period with no further multi-device dropouts reported, and the client was advised to have the electrical risk in the house checked promptly.

判断：两台华硕路由器均有故障——主路由在后台提示拆分WiFi成功、硬件层面却未生效，5G指示灯不亮；副路由的LAN口出现周期性识别不到。共同的因素在供电这一侧：路由器所插的插座松动，插拔时会让旁边的NBN设备短暂断电，而这家此前已经有NBN设备因打雷故障并更换过。这两台还是19V 1.75A的高功率机型。现场换上TP-Link路由器交由客户观察使用，期间未再反馈多设备连接断网，同时建议客户尽早对家里的电源风险进行排查。