rutvij-pandya

# Ruby(2.4.4) Module - SecureRandom - https://ruby-doc.org/stdlib-2.4.4/libdoc/securerandom/rdoc/SecureRandom.html
SecureRandom.class_eval do 
  
  CHARSET = [*"A".."Z", *"0".."9"]

  # Returns Randomly generated 6 or more char long alphanumeric string
  def self.alphanumeric(number)
    CHARSET.sample(number).join
  end
end

rutvij-pandya

## Modify postgresql.conf 

# Find postgresql.conf 

# ---- For mac users ----
cd /usr/local/var/postgres/  
vi postgresql.conf

# ---- For ubuntu users ----
cd /etc/postgresql/<version>/main

rutvij-pandya

## Gemfile

gem 'pghero'
# pg_query is used by pghero to provide suggestions to add indexes
gem 'pg_query', '>= 0.9.0'

# bundle install

## Add a route to access the pgHero Dashboard 
# You can secure its access with Devise user authentication

rutvij-pandya

# CentOS 6.5

Install rvm 
>> curl -L get.rvm.io | bash -s stable
>> \curl -sSL https://get.rvm.io | bash 
>> source /etc/profile.d/rvm.sh
>> rvm reload

Install Ruby 
>> rvm install 2.1.2

rutvij-pandya

Create new Volume (i.e, 30gb) from Panel
>> Select volume, Go to Actions/Attach
>> Select instance to attach it

Mount volume to /mnt
>> Create EBS volume.
>> Attach EBS volume to /dev/sdf (EC2's external name for this particular device number).
>> Format file system /dev/xvdf (Ubuntu's internal name for this particular device number):
>> sudo mkfs.ext4 /dev/xvdf
>> Only format the file system if this is a new volume with no data on it. Formatting will make it difficult or impossible to retrieve any data that was on this volume previously.

rutvij-pandya

Launch EC2 instance 
>> Reference - http://dennissuratna.com/rails-deployment-aws2/
Config Security group
Make server private - only accessible via NAT
>> Select Subnat option while configuring instance 
Map DNS - link web address - www.foo.com 

Basic Configuration for EC2 instance 
>> yum -y update
>> yum groupinstall -y 'development tools'

rutvij-pandya

VPC and subnet
>> Reference - http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Introduction.html
Config VPC - Config Subnet & associate with VPC
>> Reference - http://docs.aws.amazon.com/AmazonVPC/latest/GettingStartedGuide/getting-started-create-vpc.html

NAT (Network Access Translation) instance
>> Reference - http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_NAT_Instance.html
Config NAT server
>> Reference - http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_NAT_Instance.html#NATInstance
Define Routing in Subnet

rutvij-pandya

Open bash_profile file 
>> vi ~/.bash_profile 
Add Alias in bash_profile file
>> alias ssh-nat="ssh -i ~/.ssh/key-pair.pem ec2-user@1.1.1.1" # Replace with actual server ip
Save 
>> :wq
Refresh file 
>> source ~/.bash_profile 
Try Alias 
>> ssh-nat

rutvij-pandya

Each server has .ssh/authorized_keys file
Each SSH key has Private & Public key
Copy content within Pub key of relevant Private key & paste it in relevant server's .ssh/authorized_keys file
>> vi .ssh/test_ssh.pub
>> Copy content
>> ssh-nat (alias)
>> ssh-learn (alias)
>> vi .ssh/authorized_keys 
>> i - Paste content 
>> :wq - save

rutvij-pandya

# First step to AWS - learn to generate SSH key for servers

Generate Key in Mac 
>> ssh-keygen 
Give path & key name
>> Enter file in which to save the key (/Users/username/.ssh/id_rsa): /Users/username/.ssh/test_ssh
Enter password (optional)
>> Enter passphrase (empty for no passphrase): 
>> Enter same passphrase again: 
  "Your identification has been saved in /Users/username/.ssh/test_ssh.