FIELD DIAGNOSTIC — “HONEST LINK TEST

 

MARK’S FIELD DIAGNOSTIC — “HONEST LINK TEST”

Purpose:
Run three real-world tests that expose the true condition of a network link (jitter, loss, routing stability, sustained throughput).
Replaces Speedtest completely.

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COMMAND BLOCK (copy/paste and run as-is)

# 1. Stability & packet loss (50 probes to Cloudflare)
ping -c 50 1.1.1.1

# 2. Route quality (live traceroute + loss/jitter per hop)
mtr -rw 1.1.1.1

# 3. Sustained throughput test (TCP, real flow)
iperf3 -c iperf.scottlinux.com

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INTERPRETATION (brief)

1. ping

• 0% loss + tight latency → good link

• Loss > 1% → unstable

• Jitter swings > 30 ms → VPN, STT, games, Zoom all degrade

• “Destination Net Unreachable” → upstream routing failure (tower/backhaul dead)

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2. mtr

• Shows where packets die.

• Loss at hop 1 = tower or local NAT failure

• Loss at hop 2–3 = backhaul congestion/microwave link fault

• Loss only at far hops = upstream ISP issues

This is the “forensic” tool.

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3. iperf3

• Tests real, sustained throughput — no cheating, no smoothing.

• Smooth graph → link can carry load

• Bursts/stalls → congestion or jitter

• Disconnects → upstream failure

If iperf3 can’t connect at all → the link isn’t routing.

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CONCLUSION

This triple test reveals:

• jitter

• packet loss

• route instability

• tower congestion

• backhaul collapse

• VPN viability

• torrent viability

• STT reliability

• true usable bandwidth

Speedtest hides all of these.
This rig exposes them instantly.

 

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Righto — here’s your compact, portable field-diagnostic script.
Name it whatever you like; I’ll call it netcheck for simplicity.

This gives you:

• one command

• clean output

• no dependencies beyond mtr and iperf3 (install once)

• works anywhere

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1. The Script (netcheck)

Copy/paste this into a file:

#!/bin/bash

echo "===================================="
echo " Mark's Honest Link Test – netcheck "
echo "===================================="
echo

# ---- 1. PING TEST ----
echo "[1] PING: Stability + Loss"
echo "--------------------------"
ping -c 50 1.1.1.1
echo
echo

# ---- 2. MTR TEST ----
echo "[2] MTR: Route Quality (loss per hop)"
echo "--------------------------------------"
mtr -rw 1.1.1.1
echo
echo

# ---- 3. IPERF3 THROUGHPUT ----
echo "[3] IPERF3: Sustained Throughput Test"
echo "--------------------------------------"
iperf3 -c iperf.scottlinux.com
echo
echo "Done."

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2. How to install it

Save it somewhere sensible — I’d suggest:

~/bin/netcheck

Then make it executable:

chmod +x ~/bin/netcheck

If ~/bin isn’t already in your PATH, add it by editing ~/.bashrc:

echo 'export PATH="$HOME/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc

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3. How to run it

Anytime, anywhere:

netcheck

That’s it.
No mucking around.
It runs the three honest tests in sequence:

• ping → stability

• mtr → route diagnosis

• iperf3 → sustained usable throughput

You get a complete truth readout of the link without touching Speedtest or any GUI.

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4. Notes

• If mtr or iperf3 aren’t installed, do this once:

sudo apt install mtr iperf3

• If iperf3’s test server is ever unreachable (rare), swap in Cloudflare’s:

iperf3 -c speedtest.wobcom.de

But the default one is rock solid.

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If you want a version that logs automatically to a timestamped file for later analysis, I can package that too.

 

Lovely Spot

Weathered granites and white trees in open bush. Some sign of prior visits from the Clan of the Brown Butterfly but not too objectionably so.

 

The Garmin 72H is a GPS and no more. No lifestyle "hanging by your testicles from a karabiner in the Rockies" statement or any of the other marketing bullshit. It has a display that can be read on moving motorcycle and has buttons so it will work in the rain. Only cost a cuppla hundred bucks if memory serves.

GPS waypoints from Spreadsheet with Gbabel

Hotpluging; I couldn't make this work however.

It doesn’t have to recognise the GPS as a USB device provided it will mount it. You can setup the GPS in the paths and gbabel will read from the files created.  The main task is to get the UTM conversions done which gbabbel does when the unicsv file format is invoked. The documentation talks about  a grid options switch following the file type in the script and suggests you set that up. The GUI has no options for file types but you can manually insert them into the script.
Write position using this grid..
This value specifies the grid to be used on write.

Table 3.1. Grid values for garmin_txt

# idx	short	file-header	sample
0	ddd	Lat/Lon hddd.ddddd	S26.25333 E27.92333
1	dmm	Lat/Lon hddd°mm.mm	N33 56.539 W118 24.471
2	dms	Lat/Lon hddd°mm'ss.s	S25 25 26.8 E28 06 07.3
3	bng	British National Grid	TQ 18919 69392
4	utm	Universal Transverse Mercator	33 U 318293 5637154
5	swiss	Swiss grid	776519 167359

Idx or short are valid params for this option.

Example:

gpsbabel -w -i geo -f /home/mark/Documents/GPS/geocaching(1).loc -i geo -f /home/mark/Documents/GPS/geocaching.loc -x duplicate,location -o kml -F /home/mark/Documents/GPS/Waypoints_output.kml -o unicsv,grid=4 -F /home/mark/Documents/GPS/geocache.csv

You can also setup multiple input/outputs and filters.  This means you might want to retain the GUI for post survey processing. For instance you can compare two sets of data and flag instance where a point is different between the two sets by a given distance.

The intruiguing thing is that it will work when the script is copied into a terminal (watch for illegal file names ie no spaces). 

The real thumbs up is that gbabel is cross platform and though all my experimentation is being done under Ubuntu this should run just fine under windows. 

Fly Repellent that Repels Flies

http://www.naturesbotanical.biz/products.html

also Available as Desert Dwellers Insect Repellent.  The creme is made from Rosemary and Cedarwood essential oils in an olive oil base.

It is available at the Camping Stores in Kalgoorlie and shouldn’t be that hard to find in most places.

I was first told about this stuff by the “Snake Lady” a prospector in Kalgoorlie and , though I was sceptical , but bought a jar @ 20 bucks for 50 mls.

In the lake Ballard / Leonora the flies are pretty nasty – persistent in sheets that make it impossible to handle equipment safely and are a big risk from the hygiene / eye infection / fly ingestion / the whole catastrophe.  I tested it there and the stuff is impressive.  A light application will be effective for about 6 hours where the flies at worst , may just brush off your skin barely contacting you.  Mostly they hover about as if you were wearing an invisible fly hat.  Glancing down to see how your sleeves are crawling with them reminds how you would be suffering without the crème. Apparently it works for mozzies too.

This stuff is the goods !