Longhorn best practices

The following settings are provided as an example how longhorn should be configured in a production cluster, especially if it is deployed on Hetzner Cloud infrastructure.

Hetzner server nodes provide local storage and allow up to five attached volumes (with a size of up to 10TiB each) Local storage is provided by NVMe storage and therefore is much faster than the attached volumes, but limited in size (max 300GiB usable).

It is assumed that the cluster creation is already done, e.g. via terraform scripts provided by the great kube-hetzner project.

Initial configuration

Nenzyz / Add swapfile on Ubuntu

Created December 5, 2024 12:37

	fallocate -l 8G /swapfile
	chmod 600 /swapfile
	mkswap /swapfile
	swapon /swapfile
	echo '/swapfile none swap sw 0 0' \| sudo tee -a /etc/fstab
	mount -a

Nenzyz / install_AdGuardHome.sh

Created September 6, 2024 07:49 — forked from stu43005/install_AdGuardHome.sh

install AdGuard Home in Synology RT1900ac

	mkdir /opt
	cd /opt
	wget https://github.com/AdguardTeam/AdGuardHome/releases/download/latest/AdGuardHome_linux_armv7.tar.gz
	tar -xzvf AdGuardHome_linux_armv7.tar.gz

	# grep -rn '/etc/' -e 'dnsmasq'
	# netstat -lnp \| grep 'dnsmasq'
	echo "port=0" >> /etc/dhcpd/dhcpd-port-port.conf
	echo 'enable="yes"' > /etc/dhcpd/dhcpd-port-port.info
	echo "port=0" >> /etc/dhcpd/dhcpd.conf

Nenzyz / keystore add certificate

Created October 31, 2023 13:07

	# Convert pem to der
	openssl x509 -outform der -in certificate.pem -out certificate.der

	# Import
	keytool -importcert -trustcacerts -file ~/Downloads/mitmproxy-ca-cert.der -alias mitmproxy -storepass changeit -keystore /Users/<USER>/.asdf/installs/java/liberica-17.0.6+10/lib/security/cacerts

	# asdf keystore location on macOS
	/Users/<USER>/.asdf/installs/java/<JAVA_INSTALLATION>/lib/security/cacerts

Nenzyz / postgres_queries_and_commands.sql

Last active May 12, 2025 14:52 — forked from rgreenjr/postgres_queries_and_commands.sql

Useful PostgreSQL Queries and Commands

	-- show db sizes
	SELECT datname as db_name, pg_size_pretty(pg_database_size(datname)) as db_usage FROM pg_database;

	-- show and terminate
	SELECT * --, pg_terminate_backend(pid)
	FROM pg_stat_activity
	WHERE usename='postgres' AND datname='dev-dc-server';

	-- show running queries (pre 9.2)
	SELECT procpid, age(clock_timestamp(), query_start), usename, current_query

Nenzyz / cryptography_ecdsa.py

Created August 7, 2023 09:10 — forked from gabrielfalcao/cryptography_ecdsa.py

Ed25519 signing in python

	from cryptography.hazmat.primitives.asymmetric.ed25519 import (
	Ed25519PrivateKey,
	Ed25519PublicKey,
	)
	from cryptography.hazmat.primitives import serialization


	private_key = Ed25519PrivateKey.generate()
	public_key = private_key.public_key()

Nenzyz / zfsbench

Created July 30, 2023 13:58 — forked from mergwyn/zfsbench

ZFS benchmarking using fio

	#!/usr/bin/env bash

	set -o errexit

	echo $(date):Random read
	fio --filename=test --sync=1 --rw=randread --bs=4k --numjobs=1 \
	--iodepth=4 --group_reporting --name=test --filesize=10G --runtime=300 && rm test

	echo $(date):Random write
	fio --filename=test --sync=1 --rw=randwrite --bs=4k --numjobs=1 \

Nenzyz / SSLPoke.java

Created January 27, 2023 16:29 — forked from 4ndrej/SSLPoke.java

Test of java SSL / keystore / cert setup. Check the comment #1 for howto.

	import javax.net.ssl.SSLParameters;
	import javax.net.ssl.SSLSocket;
	import javax.net.ssl.SSLSocketFactory;
	import java.io.*;

	/** Establish a SSL connection to a host and port, writes a byte and
	* prints the response. See
	* http://confluence.atlassian.com/display/JIRA/Connecting+to+SSL+services
	*/
	public class SSLPoke {