# 🌐 2.84 Gbps on a Sub-$100 Upgrade — Four Cables, Worked Like Four Lanes

**URL:** <https://onehack.st/t/2-84-gbps-on-a-sub-100-upgrade-four-cables-worked-like-four-lanes/326245>\
**Category:** Tutorials & Methods\
**Tags:** networking, tips-tricks, self-hosted-tools\
**Created:** [October 5, 2026, 11:10am UTC](https://onehack.st/t/2-84-gbps-on-a-sub-100-upgrade-four-cables-worked-like-four-lanes/326245 "2026-10-05T11:10:10Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![BCBC](https://onehack.st/user_avatar/onehack.st/bcbc/32/174133_2.png) [@BCBC](https://onehack.st/u/BCBC)\
**Post date:** [October 5, 2026, 11:10am UTC](https://onehack.st/t/2-84-gbps-on-a-sub-100-upgrade-four-cables-worked-like-four-lanes/326245/1 "2026-10-05T11:10:10Z")

</div>

### 🌐 Your fibre is not the bottleneck — your cable count is

2,844.78 Mbps through four ordinary gigabit cables · under $100, because he already owned the parts

![Four lanes, one car each](https://onehack.st/uploads/default/original/3X/1/8/18202c3e72cc53369651099c0474b800c2822a28.png)

**Why he bothered** — the fibre reaching his house carries more than a gigabit.  
One gigabit cable inside was throwing the rest away, so every download, backup and VM image crawled at 940.  
**Why this is the clever part** — he fixed it without buying a network.  
Four gigabit ports already sitting on the machine became four lanes, and the far end now measures **2,844.78 Mbps down** (940.59 up, 2 ms).  
**Why you would care** — the same trick needs a spare Ethernet port, a managed switch that speaks LACP, Linux and one cable.  
You may already own your next upgrade — the only question is how many lanes you are leaving empty.  
**Why the ugly pages are here** — a loop, a wrong assumption, a false FAIL and a reboot test are the hours you would otherwise spend blind.  
Somebody else’s bad afternoon is the entire value of a build log.

**The one idea, in one picture** — four bonded cables are a road with four lanes, not one fast car.  
A speed test opens many connections at once and fills them all; a single file copy still rides one lane, so it stays near a gigabit.  
That is why the 2.84 is real, and why one lone download still looks ordinary.

**The route, in plain words**

digraph path { rankdir=TB; graph [bgcolor="transparent"]; node [shape=box, style="rounded,filled", fillcolor="#f5f7fa", color="#b9c3d0", fontname="Helvetica", fontsize=11]; edge [fontname="Helvetica", fontsize=10, color="#8a95a3", fontcolor="#5b6673"]; fibre [label="the fibre from the street"]; eero [label="the router"]; core [label="the 10G core (Dexter)"]; multi [label="the multi-gig switch (RealHD)"]; old [label="the old switch (Aruba, still good)"]; box [label="his Linux box (Mikey)\nfour gigabit ports, bonded", fillcolor="#fff4cf", color="#e0a800"]; fibre -\> eero [label="10G"]; eero -\> core [label="10G"]; core -\> multi [label="10G"]; multi -\> old [label="4 x 1G LACP", color="#e0a800", fontcolor="#8a6a00"]; old -\> box [label="4 x 1G LACP", color="#e0a800", fontcolor="#8a6a00"]; }

**What the loop taught him** — one extra cable had quietly made a second path between two switches, and the lights went wild.  
He pulled it and drew the path instead. Steal the rule: _when building LACP, draw the Layer-2 topology, not the cable count._  
**What the reboot test buys you** — the setup returns by itself after a restart, because the old configuration was copied aside and compared byte-for-byte before a single change.  
Boring, and it is the difference between a lab and a network.

**To try it** — a spare port, a managed switch, Linux, a cable. **And his line, which is the real lesson** — old does not mean useless.

> **🔢 the numbers, the four-link bond, the netplan and the loop in full**
>
> - **The measured runs** — 2,844.78 Mbps down · 940.59 up · 2 ms ping, and an earlier 2,400.48 down · 940.71 up on the same finished setup.
> - **What carries it** — an Intel i350 four-port gigabit NIC in the workstation, IEEE 802.3ad LACP, an Aruba S3500-24P on one side of the path and a RealHD multi-gig switch on the other, 10G links beyond.
> - **Why upload stays at 941** — the bonded aggregate is on his side of the path; the upstream side is one gigabit, so upload keeps its ceiling.
> - **The loop** — the workstation had an Aruba path _and_ a direct cable toward the multi-gig side, while those two switches were also linked to each other. Removing the extra cable made the intended path unambiguous.
> - **The bond config** — Netplan with systemd-networkd, four interfaces with dhcp disabled and a single bond; the old file was copied aside and verified with `cmp -s` before the change.

He did not buy a faster network. He stopped wasting the lanes he already had.