Let’s get a quick overview of Google Cloud Compute Engine from an GCP certification perspective. We will look at important certification questions Compute Engine, MIG’s, Images, Instance Templates

You will learn

• What is a Compute Engine
• Why it is important and how to set it up?
• Commands Cheatsheet

Compute

Compute Engine Fundamentals

Google Compute Engine (GCE)

• In corporate data centers, applications are deployed to physical servers
• Where do you deploy applications in the cloud?
  • Rent virtual servers
  • Virtual Machines - Virtual servers in GCP
  • Google Compute Engine (GCE) - Provision & Manage Virtual Machines

Compute Engine - Features

• Create and manage lifecycle of Virtual Machine (VM) instances
• Load balancing and auto scaling for multiple VM instances
• Attach storage (& network storage) to your VM instances
• Manage network connectivity and configuration for your VM instances
• Our Goal:
  • Setup VM instances as HTTP (Web) Server
  • Distribute load with Load Balancers

Compute Engine Machine Family

• What type of hardware do you want to run your workloads on?
• Different Machine Families for Different Workloads:
  • General Purpose (E2, N2, N2D, N1) : Best price-performance ratio
    • Web and application servers, Small-medium databases, Dev environments
  • Memory Optimized (M2, M1): Ultra high memory workloads
    • Large in-memory databases and In-memory analytics
  • Compute Optimized (C2): Compute intensive workloads
    • Gaming applications

Compute Engine Machine Types

• How much CPU, memory or disk do you want?
  • Variety of machine types are available for each machine family
  • Let’s take an example : e2-standard-2:
    • e2 - Machine Type Family
    • standard - Type of workload
    • 2 - Number of CPUs
• Memory, disk and networking capabilities increase along with vCPUs

Image

• What operating system and what software do you want on the instance?
• Type of Images:
  • Public Images: Provided & maintained by Google or Open source communities or third party vendors
  • Custom Images: Created by you for your projects

Internal and External IP Addresses

• External (Public) IP addresses are Internet addressable.
• Internal (Private) IP addresses are internal to a corporate network
• You CANNOT have two resources with same public (External) IP address.
  • HOWEVER, two different corporate networks CAN have resources with same Internal (private) IP address
• All VM instances are assigned at least one Internal IP address
• Creation of External IP addresses can be enabled for VM instances
  • (Remember) When you stop an VM instance, External IP address is lost

Static IP Addresses

• Scenario : How do you get a constant External IP address for a VM instance?
  • Quick and dirty way is to assign an Static IP Address to the VM!

Static IP Addresses - Remember

• Static IP can be switched to another VM instance in same project
• Static IP remains attached even if you stop the instance. You have to manually detach it.
• Remember : You are billed for an Static IP when you are NOT using it!
  • Make sure that you explicitly release an Static IP when you are not using it.

Simplify VM setup

• How do we reduce the number of steps in creating an VM instance and setting up?
• Let’s explore a few options:
  • Startup script
  • Instance Template
  • Custom Image

Bootstrapping with Startup script

#!/bin/bash
apt update 
apt -y install apache2
echo "Hello world from $(hostname) $(hostname -I)" > /var/www/html/index.html

• Bootstrapping: Install OS patches or software when an VM instance is launched.
• In VM, you can configure Startup script to bootstrap

Instance templates

• Why do you need to specify all the VM instance details (Image, instance type etc) every time you launch an instance?
  • How about creating a Instance template?
  • Define machine type, image, labels, startup script and other properties
• Used to create VM instances and managed instance groups
  • Provides a convenient way to create similar instances
• CANNOT be updated
  • To make a change, copy an existing template and modify it
• (Optional) Image family can be specified (example - debian-9):
  • Latest non-deprecated version of the family is used

Reducing Launch Time with Custom Image

• Installing OS patches and software at launch of VM instances increases boot up time
• How about creating a custom image with OS patches and software pre-installed?
  • Can be created from an instance, a persistent disk, a snapshot, another image, or a file in Cloud Storage
  • Can be shared across projects
  • (Recommendation) Deprecate old images (& specify replacement image)
  • (Recommendation) Hardening an Image - Customize images to your corporate security standards
• Prefer using Custom Image to Startup script

Sustained use discounts

Source: https://cloud.google.com

• Automatic discounts for running VM instances for significant portion of the billing month
  • Example: If you use N1, N2 machine types for more than 25% of a month, you get a 20% to 50% discount on every incremental minute.
  • Discount increases with usage (graph)
  • No action required on your part!
• Applicable for instances created by Google Kubernetes Engine and Compute Engine
• RESTRICTION: Does NOT apply on certain machine types (example: E2 and A2)
• RESTRICTION: Does NOT apply to VMs created by App Engine flexible and Dataflow

Committed use discounts

• For workloads with predictable resource needs
• Commit for 1 year or 3 years
• Up to 70% discount based on machine type and GPUs
• Applicable for instances created by Google Kubernetes Engine and Compute Engine
• RESTRICTION: Does NOT apply to VMs created by App Engine flexible and Dataflow

Preemptible VM

• Short-lived cheaper (upto 80%) compute instances
  • Can be stopped by GCP any time (preempted) within 24 hours
  • Instances get 30 second warning (to save anything they want to save)
• Use Preempt VM’s if:
  • Your applications are fault tolerant
  • You are very cost sensitive
  • Your workload is NOT immediate
  • Example: Non immediate batch processing jobs
• RESTRICTIONS:
  • NOT always available
  • NO SLA and CANNOT be migrated to regular VMs
  • NO Automatic Restarts
  • Free Tier credits not applicable

Google Compute Engine - Billing

• You are billed by the second (after a minimum of 1 minute)
• You are NOT billed for compute when a compute instance is stopped
  • However, you will be billed for any storage attached with it!
• (RECOMMENDATION) Always create Budget alerts and make use of Budget exports to stay on top of billing!
• What are the ways you can save money?
  • Choose the right machine type and image for your workload
  • Be aware of the discounts available:
    • Sustained use discounts
    • Committed use discounts
    • Discounts for preemptible VM instances

Compute Engine : Live Migration & Availability Policy

• How do you keep your VM instances running when a host system needs to be updated (a software or a hardware update needs to be performed)?
• Live Migration
  • Your running instance is migrated to another host in the same zone
  • Does NOT change any attributes or properties of the VM
  • SUPPORTED for instances with local SSDs
  • NOT SUPPORTED for GPUs and preemptible instances
• Important Configuration - Availability Policy:
  • On host maintenance: What should happen during periodic infrastructure maintenance?
    • Migrate (default): Migrate VM instance to other hardware
    • Terminate: Stop the VM instance
  • Automatic restart - Restart VM instances if they are terminated due to non-user-initiated reasons (maintenance event, hardware failure etc.)

Compute Engine Features: Custom Machine Types

• What do you do when predefined VM options are NOT appropriate for your workload?
  • Create a machine type customized to your needs (a Custom Machine Type)
• Custom Machine Type: Adjust vCPUs, memory and GPUs
  • Choose between E2, N2, or N1 machine types
  • Supports a wide variety of Operating Systems: CentOS, CoreOS, Debian, Red Hat, Ubuntu, Windows etc
  • Billed per vCPUs, memory provisioned to each instance
    • Example Hourly Price: $0.033174 / vCPU + $0.004446 / GB

Compute Engine Features: GPUs

• How do you accelerate math intensive and graphics-intensive workloads for AI/ML etc?
• Add a GPU to your virtual machine:
  • High performance for math intensive and graphics-intensive workloads
  • Higher Cost
  • (REMEMBER) Use images with GPU libraries (Deep Learning) installed
    • OTHERWISE, GPU will not be used
  • GPU restrictions:
    • NOT supported on all machine types (For example, not supported on shared-core or memory-optimized machine types)
    • On host maintenance can only have the value “Terminate VM instance”
• Recommended Availability policy for GPUs
  • Automatic restart - on

Virtual Machine - Remember

• Associated with a project
• Machine type availability can vary from region to regions
• You can only change the machine type (adjust the number of vCPUs and memory) of a stopped instance
  • You CANNOT change the machine type of a running instance
• VM’s can be filtered by various properties
  • Name, Zone, Machine Type, Internal/External IP, Network, Labels etc
• Instances are Zonal (Run in a specific zone (in a specific region))
  • Images are global (You can provide access to other projects - if needed)
  • Instance templates are global (Unless you use zonal resources in your templates)
• Automatic Basic Monitoring is enabled
  • Default Metrics: CPU utilization, Network Bytes (in/out), Disk Throughput/IOPS
  • For Memory Utilization & Disk Space Utilization - Cloud Monitoring agent is needed

Virtual Machine - Best Practices

• Choose Zone and Region based on:
  • Cost, Regulations, Availability Needs, Latency and Specific Hardware needs
  • Distribute instances in multiple zones and regions for high availability
• Choose right machine type for you needs:
  • Play with them to find out the right machine type
  • Use GPUs for Math and Graphic intensive applications
• Reserve for “committed use discounts” for constant workloads
• Use preemptible instances for fault-tolerant, NON time critical workloads
• Use labels to indicate environment, team, business unit etc

Compute Engine Scenarios

Quick Review

Image

• What operating system and what software do you want on the VM instance?
• Reduce boot time and improve security by creating custom hardened Images.
• You can share an Image with other projects

Machine Types

• Optimized combination of compute(CPU, GPU), memory, disk (storage) and networking for specific workloads.
• You can create your own Custom Machine Types when existing ones don’t fit your needs

Quick Review

• Static IP Addresses: Get a constant IP addresses for VM instances
• Instance Templates: Pre-configured templates simplifying the creation of VM instances
• Sustained use discounts: Automatic discounts for running VM instances for significant portion of the billing month
• Committed use discounts: 1 year or 3 year reservations for workloads with predictable resource needs
• Preemptible VM: Short-lived cheaper (upto 80%) compute instances for non-time-critical fault-tolerant workloads