maurorappa

FROM alpine:3.5
LABEL type=proxy-in
MAINTAINER Zerolatency - Mauro Rappa
RUN apk --update --no-cache add lua luarocks gcc make lua-dev musl-dev openssl
RUN luarocks-5.1 install copas
# remove fairness in copas client handling
RUN sed -i 's/90/0/' /usr/local/share/lua/5.1/copas.lua
RUN wget -O proxy-in.lua https://gist.githubusercontent.com/maurorappa/0e92df25be62bbb48535a5e0c8a8b965/raw/feb4bc8e4b8fddb41e16410ce85f9eada9f06833/proxy-in.lua
CMD ["lua","proxy-in.lua","*:8080","127.0.0.1:80"]
EXPOSE 8080

maurorappa

## This yaml formated config file handles setting
## logger information.  The values that are necessary to be set
## are seen at the bottom.  The top '_log' are only used to remove
## redundency in a syslog and fallback-to-file case.
##
## The 'log_cfgs' entry defines a list of logger configs
## Each entry in the list is tried, and the first one that
## works is used.  If a log_cfg list entry is an array, it will
## be joined with '\n'.
_log:

maurorappa

#!/usr/bin/env ruby
# No Frills script with basic dependencies
#

require 'rubygems' if RUBY_VERSION < '1.9.0'
require 'sensu-plugin/check/cli'
require 'socket'
require 'timeout'

class PingRedis < Sensu::Plugin::Check::CLI

maurorappa

#!/opt/sensu/embedded/bin/ruby

require 'rubygems' if RUBY_VERSION < '1.9.0'
require 'sensu-plugin/check/cli'
require 'net/http'
require 'json'

# Scenario: you are shipping logs to the ES cluster and you want periodically look for errors 
# the script will run any query and count the occurences, with the flags -c (critical) and -w (warning) you can trigger SENSU alarms 
# the following example will look for Fatal errors occurred between 017-02-12 and 017-02-12 and raise a critical alert if at least one is found

maurorappa

#!/bin/sh

yum update
yum install -y unzip php httpd mysql-server mysql php-mysql vim telnet

conf="                          \n
[mysqld]                        \n
port=3307                       \n
datadir=/var/lib/mysql          \n
socket=/var/lib/mysql/mysql.sock\n

maurorappa

 ! Configuration File for keepalived
global_defs {
}

vrrp_script chk_redis_master {
        script "redis-cli info replication|grep master > /dev/null"
        interval 2                      # check every 2 seconds
        weight 2                        # add 2 points of prio if OK
}

maurorappa

# -*- mode: ruby -*-
# vi: set ft=ruby :

# the envionment variable 'mode' will select the type of deployment from the yml file

require 'yaml'
mode = ENV['mode']
puts ("mode selected: #{mode}")

box_details = YAML.load_file("vagrant_ansible.yml")

maurorappa

require 'rubygems'
require 'redis'
require 'uri'

uri = URI.parse('redis://127.0.0.1:26379')
REDIS = Redis.new(:host => uri.host, :port => uri.port)

REDIS.psubscribe('*switch-master' ) do |on|
 on.psubscribe do |event, total|
    puts "Subscribed to ##{event} (#{total} subscriptions)"

maurorappa

/* ------------------------------------------------------------ *
 * file:        sslconnect.c                                    *
 * ------------------------------------------------------------ *
 * file:        sslconnect.c                                    *
 * purpose:     utility to time an SSL connection and           *
 * to compile:                                                  *
 * gcc -lssl -lcrypto -o sslconnect sslconnect.c                *
 * ------------------------------------------------------------ */

#include <sys/socket.h>

maurorappa

You can't simply run a backup on a specific node in a cluster, since its role can change to master and lead to an overload for it.
You need some intelligence to choose the right node (slave) and allow multiple nodes to execute the backup; you want to be safe without
designing a specific node to run it.

This is my approach:
* schedule the script below in any MongoDB host
* the script will exit if it's running on a master
* if it's a slave, it will wait a random interval, check if there's a lock document on the master and if not present perform the backup.

in such a way you are covered from any single node failure