andrewh

Alert Investigation: Lambda High Error Rate

Alert: Lambda High Error Rate Date: 2026-07-15 Status: Resolved (all instances Normal) Severity: P4 Slack: #sp-monitoring-alerts-prod Spark group: UK Sky Protect IoT SRE Runbook: https://sky-group.atlassian.net/wiki/x/nWHi

andrewh

Use motel with otel-cli

otel-cli is a command-line tool for creating OpenTelemetry spans from shell scripts. motel generates synthetic telemetry from topology definitions. The two tools complement each other — otel-cli instruments real commands, motel simulates entire distributed systems.

This guide covers practical ways to use them together.

Prerequisites

• motel installed
• otel-cli installed (releases)

andrewh

motel: Preview Traffic

2026-02-22T09:00:00Z

motel preview renders the effective traffic rate over time as an SVG chart. This is useful for verifying bursty patterns, scenario overrides, and ramp-up shapes before sending traffic to a collector.

Uniform traffic

A flat rate produces a horizontal line across the chart.

andrewh

#!/bin/sh
#
# Clean up a Raspberry Pi Zero W
#
# Refs:
#   - https://www.dzombak.com/blog/2023/12/considerations-for-a-long-running-raspberry-pi/
#   - https://www.dzombak.com/blog/2023/12/disable-or-remove-unneeded-services-and-software-to-help-keep-your-raspberry-pi-online/
#   - https://www.dzombak.com/blog/2024/03/running-a-raspberry-pi-with-a-read-only-root-filesystem/
#   - ChatGPT

andrewh

Keybase proof

I hereby claim:

• I am andrewh on github.
• I am andrewh (https://keybase.io/andrewh) on keybase.
• I have a public key ASC8teA31aZ0PyFgd7wQIJwy-g3yPmhCtttEZE0eW1nhAwo

To claim this, I am signing this object:

andrewh

#!/usr/bin/env python

print("""
α Α = alpha
β Β = beta
γ Γ = gamma
δ Δ = delta
ε Ε = epsilon
ζ Ζ = zeta
η Η = eta

andrewh

http-ping

$ http-ping -c 5 -u google.com
Found google.com, assuming you mean http://google.com/
HTTP-PING google.com (62.253.3.89): GET request
11K bytes from www.google.co.uk: http_seq=0 status=200 time=301.44 ms
11K bytes from www.google.co.uk: http_seq=1 status=200 time=186.29 ms
12K bytes from www.google.co.uk: http_seq=2 status=200 time=185.33 ms
12K bytes from www.google.co.uk: http_seq=3 status=200 time=288.65 ms

andrewh

-- 1. Place in ~/Library/Scripts and enable the Applescript menu via the Applescript Editor
-- 2. Substitute "vpn.example.com" and "redacted" for your VPN server and password
-- 3. Open Security & Privacy System Preferences, go to Privacy, Accessibility
-- 4. Enable Applescript Editor and System UI Server
-- 5. Trigger script from the menu
-- 6. Enjoy being connected

tell application "Cisco AnyConnect Secure Mobility Client"
    activate
end tell

andrewh

#!/usr/bin/env ruby

# qpasswd - password generator from quantum RNG

require 'open-uri'

rng = 'https://qrng.anu.edu.au/wp-content/plugins/colours-plugin/get_block_alpha.php'
ARGV.size < 1 ? pw_size = 16 : pw_size = ARGV[0].to_i
data = open(rng).read.strip.split('')
output = data.sample(pw_size)

andrewh

#!/usr/bin/env bash

set -e

FILES_TO_PRUNE="path_to_large_file_from_root_of_repo"

catch_error () {
  local cmd_name=$1
  local ret_code=$2
  if [ $ret_code -ne 0 ]; then