Iskander Ignatev ignatev

Ubuntu Server Setup - with ifupdown

The assumption here is that you're starting with a Ubuntu 20.04 LTS Server or newer, rather than Desktop, base (Ubuntu Desktop deploys NetworkManager rather than systemd-networkd by default).

The goal is networking configured for static addressing using using ifupdown, rather than the newer systemd-networkd and netplan, or (for Ubuntu Desktop) NetworkManager. It basically returns networking on Ubuntu to its Debian roots.

The physical network device name for the test machine was "ens3", it will be something else on different hardware.

NOTE: I am currently using netplan rather than ifupdown on my own Ubuntu servers. I'll keep these notes updated because the configuration is close enough to Debian that it may come in handy when I finally switch to Debian.

I recently switched over to neovim (see my screenshots at the bottom). Below is my updated config file.

It's currently synchronized with my .vimrc config except for a block of neovim-specific terminal key mappings.

This is still a work in progress (everyone's own config is always a labor of love), but I'm already extremely pleased with how well this is working for me with neovim. While terminal mode isn't enough to make me stop using tmux, it is quite good and I like having it since it simplifies my documentation workflow for yanking terminal output to paste in a markdown buffer.

These days I primarily develop in Go. I'm super thrilled and grateful for fatih/vim-go,

Run Chef scripts locally

There are several options to run recipes:

using chef-client with -z option
using chef-apply
using chef-solo

Before running Chef recipes on the machine, it should be prepared:

Virtual Hosts on nginx (CSC309)

When hosting our web applications, we often have one public IP address (i.e., an IP address visible to the outside world) using which we want to host multiple web apps. For example, one may wants to host three different web apps respectively for example1.com, example2.com, and example1.com/images on the same machine using a single IP address.

How can we do that? Well, the good news is Internet browsers

Simple collection of Groovy scripts to help me maintain some Jenkins systems.

See also https://wiki.jenkins-ci.org/display/JENKINS/Jenkins+Script+Console

	-- show running queries (pre 9.2)
	SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
	FROM pg_stat_activity
	WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
	ORDER BY query_start desc;

	-- show running queries (9.2)
	SELECT pid, age(clock_timestamp(), query_start), usename, query
	FROM pg_stat_activity
	WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'

	#Better way:
	New-LocalUser -AccountNeverExpires:$true -Password ( ConvertTo-SecureString -AsPlainText -Force 'somepassword') -Name 'someuser' \| Add-LocalGroupMember -Group administrators

	#Old:
	$Username = "su"
	$Password = "password"

	$group = "Administrators"

	$adsi = [ADSI]"WinNT://$env:COMPUTERNAME"

	import org.sonatype.nexus.repository.storage.StorageFacet;
	import org.sonatype.nexus.repository.storage.Query;
	import org.joda.time.DateTime;
	import org.joda.time.format.DateTimeFormat;

	def fmt = DateTimeFormat.forPattern('yyyy-MM-dd HH:mm:ss');
	[
	'releases'
	].each { reponame ->
	// Get a repository

	// Check if a slave has < 10 GB of free space, wipe out workspaces if it does

	import hudson.model.*;
	import hudson.util.*;
	import jenkins.model.*;
	import hudson.FilePath.FileCallable;
	import hudson.slaves.OfflineCause;
	import hudson.node_monitors.*;

	# Generate a new key
	openssl genrsa -out server.key 2048

	# Generate a new CSR
	openssl req -sha256 -new -key server.key -out server.csr

	# Check certificate against CA
	openssl verify -verbose -CApath ./CA/ -CAfile ./CA/cacert.pem cert.pem

	# Self Signed