miketheman

Adding 2 nodes to an existing 3-node ZooKeeper ensemble without losing the Quorum

Since many deployments may start out with 3 nodes and so little is known about how to grow a cluster from 3 memebrs to 5 members without losing the existing Quorum, here is an example of how this might be achieved.

In this example, all 5 nodes will be running on the same Vagrant host for the purpose of illustration, running on distinct configurations (ports and data directories) without the actual load of clients.

YMMV. Caveat usufructuarius.

Step 1: Have a healthy 3-node ensemble

miketheman

#!/usr/bin/env python

import sys
import boto
import pprint

del_flag = ''
if len(sys.argv) > 1:
    del_flag = sys.argv[1]

miketheman

from unittest.mock import patch

import boto3
from botocore.stub import Stubber


# create an ssm client
ssm = boto3.client("ssm")
# create an sqs client
sqs = boto3.client("sqs")

miketheman

"""
Add users to a Mastodon instance list.

Uses https://mastodonpy.readthedocs.io/
"""
from os import environ
from pathlib import Path

from mastodon import Mastodon
from mastodon.errors import MastodonNotFoundError, MastodonServiceUnavailableError

miketheman

Tests how GitHub renders code blocks

Code fence, no language set

    ```
    echo "foo"
    ```

miketheman

CURRENT_DIRECTORY := $(shell pwd)

TESTSCOPE = apps
TESTFLAGS = --with-timer --timer-top-n 10 --keepdb

help:
	@echo "Docker Compose Help"
	@echo "-----------------------"
	@echo ""
	@echo "Run tests to ensure current state is good:"

miketheman

DIAGRAMS := $(wildcard *.puml */*puml)
SVGS := $(DIAGRAMS:.puml=.svg)
PNGS := $(DIAGRAMS:.puml=.png)

all: $(SVGS) $(PNGS)

%.png: %.puml
	plantuml -tpng "$<"

%.svg: %.puml

miketheman

from github import Github

gh = Github('SET_GITHUB_ACCESS_TOKE_HERE')

org = gh.get_organization('SET_ORG_NAME_HERE')

repos = org.get_repos()

for repo in repos:
    if repo.archived:

miketheman

try:
    # importlib.metadata is present in Python 3.8 and later
    import importlib.metadata as importlib_metadata
except ImportError:
    # use the shim package importlib-metadata pre-3.8
    import importlib_metadata as importlib_metadata

try:
    __version__ = importlib_metadata.version(__package__ or __name__)
except importlib_metadata.PackageNotFoundError:

miketheman

class Hypermail < Formula
  desc "Hypermail is a free (GPL) program to convert email from Unix mbox format to html."
  homepage "http://www.hypermail-project.org/"
  url "https://github.com/hypermail-project/hypermail/releases/download/v2.4.0/hypermail-2.4.0.tar.gz"
  sha256 "f97995b9bb1ece888968467cdad05e3daa7662ff3e3a5739e378b4f3adeb26c6"
  license "GPL-2.0"

  depends_on "bison" => :build

  depends_on "gcc"