Study notes for the GCP Professional Network Engineer cert exam

gcp-pro-networking-cert.md

GCP Professional Network Engineer

RFC1918 IP Address Allocation for Private Internets

• determine the number of servers and IP address you need
• determine number of private hosts first
  • 10.0.0.0/8 (24-bit; Class A)
  • 172.16.0.0/12 (20-bit; 16 Class B blocks)
  • 192.168.0.0/16 (16-bit; 256 Class C blocks)
• use route summarization for better routing performance and management
  • 192.168.0.0/24 and 192.168.1.0/24 could be 192.168.0.0/23, spanning both (borrowing a bit)

CIDR Notation

• /29 8 (2^3)
• /28 16 (2^4)
• /27 32 (2^5)
• /26 64 (2^6)
• /25 128 (2^7)
• /24 256 (2^8)
• /23 512 (2^9)
• /22 1,024 (2^10)
• /21 2,048 (2^11)
• /20 4,096 (2^12)
• /19 8,192 (2^13)
• /18 16,384 (2^14)
• /17 32,768 (2^15)
• /16 65,536 (2^16)
• /15 131,072 (2^17)
• /14 262,144 (2^18)
• /13 524,288 (2^19)
• /12 1,048,576 (2^20)
• /11 2,097,152 (2^21)
• /10 4,194,304 (2^22)
• /9 8,388,608 (2^23)
• /8 16,777,216 (2^24)

Identity and Access Management (IAM)

Identity Access Management (IAM)

• Authentication (AuthN) and Authorization (AuthZ)
• who can do what on which resource
• types
  • Google Account
  • Service Account
  • Google Groups
    • GSuite (Workspace) Domain
    • Cloud Identity Domain
• roles
  • Primitive
  • Predefined (more granular)
  • Custom (most granular)
• IAM policy
  • bindings consist of members and roles
  • identity (who)
  • role (can do what)
  • resource (on which resource)
• hierarchy
  • Organization
    • Folder
      • Project
        • Resources
  • policies are inherited from top down, and union of all parent policies
• key people
  • OrgAdmin
    • NetworkAdmin (networking - usually at org level)
      • KNOW PERMISSIONS AND WHAT EACH ALLOWS YOU TO DO
    • SecurityAdmin (security policies - usually at org level)
    • ComputeInstanceAdmin

Network IAM Roles

Defining IAM Policies

• selecting the default policies that enforce organization standards across all resources

Determining the Resource Hierarchy

• create the structure of how roles will be assigned to resources

Delegating Responsibility

• select the team members that will be assigned the IAM roles to implement the configuration of Network and Security

Key roles:

• roles/compute.networkAdmin (Compute Network Admin)
  • over 200 permissions for compute network resources
  • doesn't create firewalls, assign IAM roles, or SSL certs
• roles/compute.securityAdmin (Compute Security Admin)
  • over 50 permissions for computer security
  • firewall, SSL
• roles/compute.xpnAdmin (Compute Shared VPC Admin)
  • 14+ permissions
  • administer shared VPC networks
• roles/compute.networkViewer (Compute Network Viewer)
  • 14+ permissions
  • read-only access to Compute Engine networking
  • granted to Service Accounts

Can view roles and assignees in Console or Gcloud SDK

• gcloud iam roles (copy, create, delete, describe, list, undelete, update)
  • gcloud iam roles list --filter="network"
  • gcloud iam roles describe <paste> (lists available permissions)
• gcloud iam list-grantable-roles (list IAM grantable roles for a resource)
• gcloud iam list-testable-permissions (list IAM testable permissions for a resource)

Creating Custom Roles

• need getIamPolicy and setIamPolicy permissions to set IAM role

Service Accounts

• Created at project level
• if you assign service account to Compute Engine instance, it uses IAM instead of access scopes, for permissions
• granting serviceAccountUser role to users allows them to impersonate and act on resources as SA (like sudo or actAs)
• need to understand how to audit service accounts

Commands in GCloud SDK:

• gcloud iam service-accounts
  • list and --filter="serviceAccounts"
  • disable <email-address>

Designing, Planning and Implementing a VPC Network

GCP Global Network

GCP computing architectures meet you where you are. All regions are connected by a private global network.

• Global
  • Region
    • Zones
      • Infrastructure
        • Resources

Ingress to GCP

• Premium Tier: Traffic from your users enters Google's network at a location nearest to them.
• Standard Tier: Traffic from your users enters Google's network through peering, ISP, or transit networks in the region where you have deployed your GCP resources.

Egress from GCP

• Premium Tier: Egress traff is sent through Google's network backbone, leaving at a global edge POP closest to your users.
• Standard Tier: Egress traffic is sent to the internet via a peering or transit network, local to the GCP region from which it originates.

Making a VPC

• REF: https://cloud.google.com/vpc/docs/vpc

Components

• Mode (automatic or custom)
• Subnet
  • Name
  • Region
  • IP Range
    • Primary (all subnets have only 1 primary range)
    • Secondary (subnets may have up to 20 secondary ranges; allows for separation of infra (VM) from containers or multiple services running on VM)
  • Alias IP (associating more than one IP address to a network interface)
    • allows one node on a network to have multiple connections to a network, each serving a different purpose
    • can be assigned from either primary, or secondary subnet ranges

Default, Auto, Custom VPCs

• Default (named "default" and uses Auto Mode)
• Auto (VPC assigns predefined range in every region)
  • starts with /20 range and can be expanded to /16 range (65,534 addresses)
• Custom (recommended in production - you completely control)
  • minimize collision risk (connecting, hybrid, peering, etc.)
  • cannot be changed to Auto mode after
  • starts with /12 range and can be expanded to /8 range (to be confirmed)

Reserved IPs

• first 2 addresses, and last 2 addresses are reserved by GCP
• Network (xxx.xxx.xxx.0)
• Gateway (xxx.xxx.xxx.1) - don't respond to ping traffic
• Second-to-last (xxx.xxx.xxx.254) - reserved for potential future use
• Broadcast (xxx.xxx.xxx.255)

DHCP, DNS, Metadata

• Internal IPs
  • IP address allocated to VMs by DHCP from regional subnetworks
  • DHCP renews every 24 hours
  • Hostname and IP address are registered with internal DNS
  • Alias IP - additional IPs assigned to a VM, mapped to or is a primary IP
• External IPs
  • External IP address assigned from a pool of ephemeral IPs managed by GCP
  • DHCP renews every 24 hours
  • VM doesn't know about the external IP, mapped to internal IP by the VPC
    • mapped by Metadata server
  • Allows communications from outside the project
• Metadata (Internal DNS)

VPC Routes

In GCP, a route consists of a single destination CIDR and a single Next Hop. Route is a way or course taken in getting from a starting point to a destination.

System-generated routes

• Subnet routes - created by GCP any time a primary or secondary subnet is added to a VPC
• Default - whenever a resource is created, GCP creates a default route
  • defines path out of network (i.e. to the Internet)
  • provides standard path for Google Private Access
  • can default and replace with custom route (NAT gateway)

Custom routes

• Static
• Dynamic

Comparison

Routing Priority

• Subnet routes
  • Custom routes
    • Default routes
      • Drops the packet

VPC Firewall Rules

Distributed virtual firewall controlling ingress and egress traffic for a single VPC.

Implied rules

• ingress: deny all by default (cannot view in logs so would have to create same with higher priority)
• egress: allow all by default (cannot view in logs)
• priority lower than all other rules, not visible, not removable

Components

• Priority (0 - 65535; 0 is highest priority; exits on first match)
• Action on match (allow or deny; one or other)
• Direction (ingress or egress)
• Protocols and ports (TCP, UDP, ICMP, IPIP)
• Source / Destination (source IP range, destination IP range)
• Targets - what to take action on (all instances, target tags, service accounts)
  • Secondary filter - narrow rules (target tags, service accounts)
• Enforcement status (enabled or disabled)
  • enforced at the instance level

Summary

• VPC object can be in any datacenter and is global
• To access resources in a region, we assign a subnet to that region
• Routes are created when you create your subnet
• In each region their are zones
• Resources consumed by assigning IP addresses from subnet
• Firewall rules are enforced at the instance level

VPC Peering

• Peering: Make or become equal or the same length.
• Allows us to build SaaS ecosystems in GCP making services available privately across different VPC networks within or across different organizations.

Overview

• Allows private communications between VPC networks without an external IP
• Connection must be established on both sides
• Subnet ranges cannot overlap

Routing

• No granular routing; use firewall rules to control traffic
• Firewall rules created separately on both sides
  • must use as no way to exclude VMs, etc. from peered network
• not automatic; must use and export custom routes
• no transitive routing supported (A - B - C) [no A->C]

Traditional connectivity

Peered connectivity (reduced latency, increased security, decreased egress costs)

Shared VPC

A way to centrally manage network resources within a host project and share them to any number of service projects.

Benefits

• centralizes network administration by sharing a VPC across projects
• relies on IAM roles to share network resources

Key IAM roles that make VPC sharing possible:

• Organization Admin
  • Shared VPC Admin
    • Network Admin (network resources, routes, subnets)
    • Security Admin (firewall rules and SSL certs)
    • Service Project Admin (grant Network User role to use resources)
      • Network User (assigned to all service project users, in order to consume resources)
• Required roles to create Shared VPC Network
  • roles/compute.xpnAdmin
  • roles/resourcemanager.projectIamAdmin

Concepts

• Service Project resources are not required to use Shared VPC resources and can use local (unless restricted by Org policy)
  • instances in service project must use external IP address to find in that same service project (even if internal IP)
• Hybrid connectivity best connected to Host Project, and shared with Service Project
• Load Balancing is managed in the Service Projects
• GKE: Alias IPs must be created BEFORE service project requests a GKE Cluster

Summary

• Host project can have more than one VPC; all are shared VPC
• Host and service projects attached at project level
• Project cannot be host and service project simultaneously
• Can only connect service project to one host project at a time
• Resources objects obtain IP address information from shared VPC network

Illustrations

Cloud NAT

Lets your compute VM instances and GKE container pods communicate with the internet using a shared public IP address.

Benefits

• Security - create instances without public IP addresses
• High Availability - Managed service without user intervention
• Scalability - Seamlessly scales with the number of instances and volume of network traffic

Overview

• specific to one region
  • only instances in that region can use Cloud NAT
  • if resources in multiple regions, must create Cloud NAT gateway for each region
• choose ranges
  • Primary & Secondary
  • Primary only
  • Selected subnets
• Outbound NAT traffic only (no inbound)
• VM with external IP does NOT need to route through NAT

NAT translation example

Configuration

• Minimum ports per VM (allows up to 64K ports)
  • Default 64 ports per VM
    • VM ports assigned 32000 - 33023
    • support approx 1000 VMs
  • Increasing to 1024 for container workloads
    • support approx 64 VMs (keep in mind for IPs required for GKE cluster and number of nodes)

Private Google Access

Provides a methods for VMs to reach public IP addresses of Google APIs & Services through the VPC network's default internet gateway, while not traversing the public internet and not requiring an external IP. Instances with external IP do not use PGA.

Overview

• only instances with internal-only IP uses
• enabled On/Off on a per-subnet basis
  • add firewall rule to allow egress to all IP (0.0.0.0/0)
    • optionally use network tags to limit which VMs can access
  • add DNS entry for *.googleapis.com
    • restricted.googleapis.com
    • private.googleapis.com

Summary

Kubernetes, Clusters & VPC Interactions

Kubernetes Cluster Networking

Cluster Components

Control Plane (a.k.a. Master) - runs on Google Resources [managed]

• etcd (distributed persistent state store)
• kube-api-server
• kube-schedulers
• kube-controller-manager
• cloud-controller-manager

Workers

• Node Pool (groups of nodes)
• Node VM compute instances
  • kubelet
  • kube-proxy

Container Networking

• nodes - vm instance running Kubernetes agents (default /20, min /29, max /8)
  • best practice: don't exceed 500 nodes
• pods - unit of deployment, one or more containers + storage (default /14, min /19, max /9)
  • rolling updates, so need at least double max pods
  • best practice: don't exceed 500,000 pods
  • POD IP address range is a single range assigned at cluster creation and cannot be changed
• services - endpoint for application access (default /20, /27, max `/16)
  • serve as static IP for pods in cluster which can come and go
  • Service IP address range not primary vpc
  • allows pods to scale

GKE Cluster IP Allocation

Zonal vs Regional Cluster

• Zonal default has single control plane instance
• Control plane can be inaccessible to make cluster updates during maintenance/upgrades
• Nodes share single regional subnet

Regional Cluster

• nodes spread across multiple zones in region
• Control plane at least 3 instances across zones so higher availability
• Nodes share single regional subnet

Routes-based Cluster

• legacy
• move traffic through cluster using routes
• IP range used for BOTH pods and services and the last /20 of range used for services
  • If default /14 range assigned, total IPs is 262,144
  • Last /20 is 4,096 addresses for Services
  • So Pods have 258,048 addresses available (/14 - /20)
• IPs assigned to pods by carving subsets from Pod IP range
• IP range is single range assigned to pods at cluster creation
• max pods/node of 110 allocates 256 IPs per node (/24 CIDR)

VPC Native Cluster (Alias IP)

• acquire addresses from regional VPC subnet
• able to customer max pods/node, and impact min/max nodes in cluster
• able to set NEGs as backend for load balancer
• only option to use Shared VPC clusters

GKE Private Clusters

Default

• master and nodes have external IP address
• Authorized Masters can be enabled for BOTH private and public clusters
• must add Master IP Range to cluster so peering can be set up for private RFC1918 communication between control plane and nodes

Public Master / Public Nodes

• default configuration
• all have external IPs

Public Master / Private Nodes

• nodes do not have external IP address
• control plane (Public Master) still accessible with external IP
• need Cloud NAT for pods to reach internet
• best to enabled Master Authorized Networks to protect control plane (IP whitelist)

Private Master / Private Nodes

• need new internal IP range (i.e. 172.16.0.0/28)
• must assign Master Authorized Network(s) to allow bastion, etc. to access nodes
• need Cloud NAT for pods to reach internet
• peering-route- will be added to routes table for managed control plane with new IP range

Shared VPC Clusters

• create IP ranges in Host Project PRIOR to cluster creation
• Only supported by VPC-Native Clusters (Alias IP)
• grant cluster service account IAM role on host project
  • Host Service Agent User role (roles/container.hostServiceAgentUser)
  • user creating cluster MUST have Network User role (roles/compute.networkUser)

Network Policy

Pod and Service network security. Isolating Pods and Services. By default pods are not isolated.

• enable at cluster creation time, or after cluster creation
• need at least N1-Standard1 size to accommodate additional resources
• GKE will recreate all cluster nodes (NOTE: if maintenance window it will not run until next schedule maintenance)
• when enabled, all pods still can communicate until you define policy rules (YAML file)
• example deny all

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: default-deny-ingress
spec:
  podSelector: {}
  policyTypes:
  - Ingress

• example web to database

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: database-allow-from-web
spec:
  policyTypes:
  - Ingress
  podSelector:
    matchLabels:
      app: database
  ingress:
  - from:
    - podSelector:
        matchLabels:
          app: web

Summary

Load Balancing

Load Balance Overview

Acts as traffic director to multiple backends to allow scaling.

• HTTP(S) load balancer
  • layer 7 for HTTP and HTTPS applications
  • ports 80, 8080, and 443
• TCP load balancer
  • layer 4 load balancing or proxy for applications that rely on TCP/SSL protocol
• UDP load balancing
  • layer 4 load balancing for apps that rely on UDP protocol

To know

• key difference of proxy load balancers (terminates incoming connections, opens new connections to backend)

Components

• Forwarding Rule (external IP [VIP = anycast IP]) - fwd rule for IPv4 and another for IPv6
  • Target Proxy (terminate request) - HTTP or HTTPS
    • URL map (L7 URI to route to backends, or storage bucket)
      • Backend service (instance group and serving capacity metadata; specify which health checks performed)
        • Instances
        • Storage buckets
        • MUST HAVE firewall rule for health check for (130.211.0.0/22 and 35.191.0.0/16)

Balancing Mode

• tells LB system when backend at full stage
• if full, new requests automatically routed to another

Architecture

Global Load Balancer - HTTP(S) and Use Cases

• Premium Tier
  • global external IP address (IPv4 or IPv6)
  • "anycast IP"
  • traffic routed to location nearest to user
• Standard Tier
  • regional external IP address (IPv4)
  • only distribute traffic to VMs in single region
  • traffic routed to location where backend instances are located

TCP & SSL Global Load Balancers

• does not support port 80

  • 25, 43, 110, 143, 195, 443, 465, 587, 700, 995, 1883, 5222

• Proxy load balancers (TCP / SSL)

  • global services and not single region
  • specific ports so any other, use Network load balancers
  • original port/IP address not preserved by default
  • target proxy terminates connection; opens another to backends (why losing original IP info)
  • can configure though "proxy protocol rules" to save source IP/port info
  • session affinity (route subsequent requests to same backend instances)
  • backend services manage health checks and detect if available to send traffic

Components

Firewall rules (allow health checks)

Summary

Network Load Balancer

Regional non-proxy load balancer that does not terminate client connections but allows them to pass through to our GCP backends.

• within a single region, the load balancer services all zones
• does not modify source IP or port
• instances chosen at random
• existing traffic sent to same server using source IP/port and destination IP/port hash
  • no session affinity, but target pools provides that persistent connection
• does not load balance traffic within GCP network
• responses go directly back to client, not through load balancer
  • industry term: direct server return
• must run basic web server on each instance so HTTP health checks on port 80

Key difference

• GCP recommends allowing all IP addresses 0.0.0.0/0

Components

Summary

Internal Load Balancing

• Allow higher availability and flexibility in rolling updates, maintenance
• only RFC1918 addresses in same region (not traffic from public internet)
• internal fwd rules must be in same subnet
• each uses one regional backend service (must have 1 IG and health check)
• no UDP health checks, so must run a TCP service to respond to health check
• can configure failover backends if a configurable threshold of backend not responding
• configure firewall rules for internal traffic source ranges

Managed Instances

• instance template
  • zonal, regional (recommend 3 minimum instances)
    • managed instances
      • autoscaling policy (default 60 second cool down period; configurable)
    • unmanaged instance
      • no autoscaling policy

To know:

• rolling update and canary (how to)
• autoscaling target utilization methods
  • Average CPU utilization
  • Cloud Monitoring metrics
  • HTTP load balancing serving capacity (utilization or requests/sec)

Summary

Network Endpoint Groups

Logical groupings of IPs and ports representing software services instead of entire VMs

• VPC
  • subnet
    • region/zone
      • default port
        • (Add Network Endpoint): VM, container, or apps
          • add IP/Port of app running

Highlights

• every IP address must be in same subnet
• VM instance must be in same zone as NEG
  • network interface must be in same subnet in VPC network
• if using NEG in load balancer, all other backends MUST BE NEGs
• IP must be primary address or alias IP
• can add same NEG for more than one backend service
  • can add same IP/port to multiple NEGs

To know

• you cannot use balancing mode of UTILIZATION for backend services that use zonal NEG as backend

  • only use balancing modes RATE or CONNECTION

• Console

  • Compute
    • Network Endpoint Groups

Cloud Armor Policies - Whitelisting and Blacklisting IPs

Security Policies are sets of rules you define to enforce application layer firewall rules protecting externally-facing application or services. Each rule is evaluated with respect to incoming traffic.

• "Service firewall rules)"
• Operates at GCP edge, closest to source, preventing unnecessary consuming resources
• Not supported for internal traffic
• Check which LBs it supports (formerly just HTTP(S) load balancing)
• "Deny lists" or "Allow lists"
• 5 IPs or ranges per rule

IAM Roles

• Compute Security Admin (create, modify policies)
• Compute Network Admin (assign policies to backend service)

DDoS scenario

Preview mode

• log actions to see how it works before applying rules to traffic

DNS and CDN Network Services

Cloud DNS

Three zones available using Cloud DNS

• Internal DNS
  • cannot be turned off; automatically created by Google Cloud
  • [INSTANCE_NAME].[ZONE].c.[PROJECT_ID].internal
• Private Zone
  • contains DNS records only visible internally within your GCP network(s)
  • Supports DNS Forwarding and DNS Peering
• Public Zone
  • visible to the internet. Usually purchased through a Registrar.

Managed DNS Zones

• Private and Public Zones

Creating a Private DNS zone

• Public or Private
• Zone name (i.e., research-acme-com)
• DNS name (i.e., research.acme.com)
• Description (optional)
• Options
  • Default (private)
  • Forward queries to another server
  • DNS Peering
  • Managed reverse lookup name
• Networks
  • multi-select

Then Create record set

• A, CNAME, etc.

Create a Public DNS zone

• Zone name (i.e., dev-acme-com)
• DNS name (i.e., dev.acme.com)
• DNSSEC (Off)
  • On
  • Off
  • Transfer
• Description (optional)
• then add new Nameserver records pointing to GCPs nameservers

Migrating existing public zones

• Create public zone
• Export records from existing on-premises network
  • BIND or YAML format
• Import DNS Records from on-premises
  • WARNING: if SOA (start of authority) records, use the delete-all-existing flag to replace with ones from Cloud DNS
• Update name servers to Cloud DNS name servers at Registrar

DNS Resolution Order on GCP

• when we create a public zone, it's the LAST PLACE resolver looks to resolve a domain name

Summary

DNS Forwarding and DNS Peering

• Forwarding - provide inbound and outbound between on-prem and Cloud DNS (hybrid DNS)
  • CANNOT USE TO FORWARD BETWEEN 2 GCP ENVS REGARDLESS OF DIRECTION
• Peering - extend DNS zones between VPC networks

DNS Resolution Order on GCP

DNS Policy (forwarding rules) - alternative to forwarding

DNS Peering

Summary (Top 5)

• Private Zone
  • Cloud DNS private zones support DNS services for a GCP Project. VPCs in the same project can use the same name servers.
• DNS Forwarding for Private Zones
  • Overrides normal DNS resolution of the specified zones. Instead, queries for the specified zones are forwarded to the listed forwarding targets
• DNS Peering for Private Zones
  • lets you send requests for records that come from one zone's namespace to another VPC network
• DNS Policy Outbound
  • when enabled in Cloud DNS, forwards all DNS request for a VPC network to name server targets. Disables internal DNS for the selected Networks
• DNS Policy Inbound
  • create an inbound DNS Policy to allow inbound connections from on-premises systems to use that network's VPC name resolution order

DNS Security

Protects public domain zone from spoofing or impersonation by a 3rd-party DNS server.

Cloud DNSSEC for Public Zones

• DNS zone for your domain must serve special DNSSEC records for public keys (DNSKEY) and signatures (RRSIG) to authenticate your zone's contents
• enabling
  • click "Registrar setup" and copy the DS line and paste at registrar
• disabling
  • disable at registrar first, before turning off
• transfer

Migrating Public Zones to GCP

• create public zone
• export on-prem records
• import records
• update registrar

Migrating DNSSEC signed zones to GCP

• create public zone
  • select DNSSEC as "Transfer"
• export DNS records (including original key)
• import records
• update registrar
• FINAL STEP: set DNSSEC to "On"

Summary

Content Delivery Network (CDN)

Shorten physical distance that data has to travel to get to our users to improve site rendering speed and performance. Stores a cached version of content in multiple geographical locations.

Requirements

• Premium Tier network (global network)
• Global HTTP(S) Load Balancer (fetches content from backends)
• Edge Location Cache Server

Types of content

• Images
• Video
• Audio
• Other
• Up to 5TB in size

Global user experience

Terminology

• Hit - when user request filled from the edge pop location
• Miss - if user request arrives and CDN does not have the file
• Fill - Cloud CDN initates request to source to fill request
  • no fill until request enters GCP network at that POP

Summary

Cloud CDN Cache Control

• apply correct expiration settings for time-sensitive content
• creating custom cache keys (e.g., remove hostname of URI and increase cache hit ratio)
  • use Cache invalidation (use folder structure instead of individual files: 1 per minute rate)
    • if want to invalidate before expire date
  • caches only update changes to files (diffs only)
• settings
  • s-maxage (priority)
  • maxage
  • Expires

Signed URLs

Give public temporary access to content without signing in.

• 128-bit key used for signing URL
  • name
  • creation method (automatic)
• cache-entry max age

Needed IAM role

Summary

Monitoring Network Operations

Observability is a measure of how well internal states of a system can be inferred from knowledge of its external outputs.

Managing Network Operations

Log entries standard fields

• actor
• logType
• logName
• severity
• timestamp

Architecture

Components

• Logs
  • Cloud Logging API
    • Cloud Logs Router
      • Exclusion filter
      • Inclusion filter
        • Log sinks
          • Cloud storage
          • BigQuery
          • Pub/Sub (3rd-party exports too)
• Log buckets
  • _Default (30 day default retention)
  • _Required (400 day retention, not configurable)

IAM roles

• Logging Admin - full control over all logging services
• Logs Configuration Writer - inclusion/exclusion filter configurability
• Logs Viewer - view non-private log data and configs
• Logs Writer - service accounts must have
• Private Logs Viewer - data access and transparency logs access

Cloud Logging Agent

• for 3rd party solutions/apps
  • need Log Writer IAM role for service account
  • if on-prem or other cloud, need service account with private key

Summary

VPC Flow Logs

• VPC network monitoring
• Forensics
• Security analysis
• Cost control / forecasting

Provide a packet-level view into how our VPC network is functioning.

Example Connection

ipConnection info

• 5-tuple (dest_ip, dest_port, protocol, src_ip, src_port)

Good to know: both SRC and DEST info logged for every VM instance (even if within GCP network)

Cost control (aggregation, sampling)

• sampling controls how much is stored (default 50%; quickly find issue set to 100% for troubleshooting)
• can turn on/off as needed
• stores in _Default for 30 days; if need longer then set up log sink export

Firewall Rule Logs

Allows us to verify and analyze the effects of firewall rules on our network traffic.

• not sampled; every connection is logged

IAM roles to enable rirewall rule Logging

• compute admin
• compute security admin
• owner or editor

IAM roles for firewall rule Viewing

• logging viewer
• owner, editor, or viewer (primitive roles)

Default rules

• ingress - deny all - 65535 priority (not logged and not editable)
• egress - allow all - 65535 priority (not logged and not edibable)
• to log:
  • create similar rule with higher priority (any priority with lower number than defaults)

Example ALLOW and DENY logs

WARNING / Troubleshooting

• default deny-all rules if logging, will generate a lot of log entries (cost)
• only works for TCP/UDP and no other protocols (i.e. ICMP)

Summary

Cloud Monitoring

We create pictures of what is going on; proactive and predictive operations. By collecting measurements over time, we can predict the pattern of events or take automated action based on the state of the environment.

Components

• Dashboards
• Uptime Checks
• Alerting Policies
• Notification Channels
• Groups

Metrics components

• Monitored resource (can be CPU, disk IDs)
• Metric types (e.g., "gauge")
• Time-series (points: collection of metrics over time)

Workspace

• single project for IAM permissions, agents, users
• takes name of project where created
• can monitor up to 100 GCP projects
• best practices
  • create separate project for Workspace
  • install monitoring agent on all GCP resources

IAM Role for VM service account

• Monitoring Metric Writer Role
  • if 3rd-party, Service Account private key

Summary

Managing Network Operations - Need to Know

Hybrid Networks

Establishing private connections between our VPC network and existing on-premise or multi-cloud network infrastructure.

Hybrid Connections

• VPN - lets you securely connect GCP resources to your own private network
  • uses IKEv1 or IKEv2 to establish IPSec connectivity
• Interconnect - lets you establish high bandwidth, low latency connections between your GCP networks and on-premises infrastructure
• Cloud Routers - enable dynamic route updates between your VPN and non-Google network
  • Regional
  • Global

Colocation Facility

• On-premises - Colocation Facility (Edge POP) - Google Cloud Platform
  • colocation facility providers establish circuit between colo and GCP establishing layer 2 connectivity
  • each "metro" metropolitan area
    • select colocation facility and metro where the Interconnect will live
    • select location close to on-premise location to reduce latency
    • each metro supports a subset of regions
    • more cost effective to avoid inter-region egress costs
    • each colocation facility supports specific regions

LOA-CFA

• Letter of Authorization and Connecting Facility Assignment (LOA-CFA)
  • Google sends email to facility provider to provision cross connect between Google and provider

Edge Availability Domain

• Each colocation facility has at least 2
• prevents outage as only 1 down at any one time for maintenance

Network Service Provider

• Colocation facility vendor
• enables establishing shared connectivity between provider and GCP

Dedicated Interconnect

• colo provider provisions circuit between our provider and Google's Edge POP

Partner Interconnect

• useful if our datacenter in physical location that cannot reach Google partner colocation facility
• or if bandwidth needs

VPN IPSec

• 3GB per tunnel, up to 8 tunnels

Direct Peering

• exchange routes and next hop is Google Global network; default IGW or VPN tunnel
• discount egress rates (no charge for peering)

Carrier Peering

• works same as direct peering
• uses shared network from GCP provider

Dedicated Interconnect

• Connect your on-premise network to Google Cloud network by connecting new fiber to your equipment
• LOA-CFA specify bandwidth needs for the business
• establish BGP session between on-premises router and GCP Cloud Router

Order

• name
• location
• suggest 2nd for SLA for redundancy

Redundancy

• company name
• technical contact

VLAN Attachment (can add to existing)

• Allocates a VLAN on an Interconnect connection and associates that VLAN with a specific Cloud Router
• name
• Cloud Router
• VLAN ID
• Allocate BGP IP address
• Bandwidth (max 50Gbs)

Partner Interconnect

Provide connectivity between GCP and our network through a 3rd-party provider

• should still use 2 zones and 2 connections for high availability

Setup

• select colocation facility
• connect on-premises network to facility (closest to our network, and GCP region)
• some offer layer 2, and layer 3
  • common is layer 3 TCP/IP connectivity

Order

• check connection
  • have provider
  • find a service provider
• check VPC network
• region
• VLAN attachment name
• Cloud Router
  • advertise all subnets OR
  • custom routes (also can advertise all, plus additional)
• adding VLAN attachment, Google generates Pairing key (one time) for service provider to set up
  • provide pairing key to partner
  • no need for LOA-CFA since existing connection with Google already
• layer 2 needs /24 range and ASN

Cloud VPN

• need Cloud VPN and Cloud Router
• IPSec = Internet Protocol Security
• traffic over public internet, but authenticates and encrypts traffic on both sides

HA VPN

• 99.99 SLA
• VPN Gateway (interfaces)
  • Tunnels
    • IP of remote gateway
    • IKEv1 or IKEv2
      • pre-shared key (generate and copy)
    • Routing
      • dynamic ONLY FOR HA
      • route-based
      • static routes
    • BGP session (peer device must support BGP)
      • peer ASN
      • Cloud Router BGP IP / BGP peer IP
      • advertisement of route options

HA VPN active/passive (recommended)

• in event of failure we have enough capacity

Need to know:

• difference between 99.9 and 99.99% availability
• ASN = autonomous system number
• MTU 1460 default (can adjust to reduce latency)
  • weigh cost implications
• against terms of service to connect two on-premises connections through VPN

Summary

VLAN attachments

Used with both dedicated and partner interconnect

• need physical connection between our network and GCP colocation facility
• after connection setup, can use cloud console to set up VLAN attachment
• binds our Cloud Router to our VPC and enables ability to send routes
• not redundant
  • need separate cloud router in different region
• for Partner Interconnect, creates VLAN attachment pairing key (waiting for service provider)
  • layer 3
  • for layer 2, need dedicated connection, ASN

Setup

• configure interconnect
• add VLAN attachment
• select project
  • name
  • router
  • VLAN ID
  • capacity (1Gb/s)

Overview

To know about HA

• zone name (zone 1) in each region, need multiple in each region for redundancy as zone 1 may be under maint in both regions

Multiple VLAN attachments

• advertise MED values
• sets up equal cost multipath routing (ECMP)

Cloud Router

• Not a physical device. Software defined.
• Establish connection between on-premises network and GCP network.
• uses BGP routing protocol
• if using internal load balancing, recommend regional routing mode (vs global) to reduce risk of lost connectivity

Private ASN

• 64512 - 65534 and 42000000 - ...

Redundancy

Use cases and components

Mode

• Regional (default) - only share subnets available from region
• Global - shares all VPC networks where subnets are provisioned

Peered Connections

Direct connection between Google's network and another network to support the exchange of traffic.

Overview

• no direct connection
• global routing only, no BGP routing
• should use VPN tunnel to add encryption across
• no setup or maintenance
• discounted egress rates

Direct Peering Connections

• need 24/7 NOC
• minimum traffic requirements (10gbs)

Carrier Peering Connections

• 1/3 discount on egress costs may justify extra provider costs

Summary

Highly Available Connections

Availability

• if customer cannot access a service at any time, it's "unavailable"
• call it "downtime"

Deciding

• based on availability, make sure business needs are met

Architectures

• 99.9%
• 99.99%

Autonomous System Numbers (ASN)

• group of routers that shared network information to make connectivity possible
• routing on BGP supports only destination-based forwarding paradigm
• forwards package based on the destination path
  • routes based on destination IP address
  • routing table describes the path to reach networks
    • in case of route path failure, uses alternative routes

NextHop

Multi exit discriminator (MED)

• like a "tie breaker" to help router decide route (lower value wins)

Equal-cost multi-path (ECMP)

Maximum Transmission Unit (MTU)

• remember outer packet adds encryption so need 75 lower than 1460 max so data can be routed

Partner Interconnect NEEDS PUBLIC ASN

• all others use private