1. Overview
   1. Google Cloud resources are hosted in multiple locations worldwide
   2. These locations are composed of regions with zones within those regions
   3. Putting resources in different zones in a region provides isolation from many types of infrastructure, hardware, and software failures
   4. Putting resources in different regions provides an even higher degree of failure independence.
   5. Design robust systems by spreading resources across different failure domains
   6. All Compute Engine resources are either global, regional, or zonal
   7. Images are a global resource, but persistent disks are either regional or zonal resources
   8. The scope of the resource determines how accessible the resource is to other resources
   9. Global resources are accessible by resources in any region or zone, so virtual machine (VM) instances from different zones can use the same global image
   10. Regional resources are accessible only to resources within the same region
   11. A regional static external IP address is accessible only by resources within the same region
   12. For a VM instance to use a specific static external IP, the instance must be in a zone that is in the same region as the address
   13. The scope of the resources indicate how accessible they are for other resources
   14. All resources, whether global, zonal, or regional, must be unique within the project
   15. Every resource in Compute Engine must be uniquely named across the project
2. Global
   1. Global resources are accessible by any resource in any zone within the same project
   2. Global resources do not need a scope specification
   3. Global static external IP addresses are a global resource and are used for global load balancers: HTTP(S), SSL proxy, and TCP proxy
   4. Images are used by any instance or disk resource in the same project as the image
   5. Google provides preconfigured images that can be used to boot instances
   6. Users can customize preconfigured images, or build their own image
   7. Optionally, users can share images across projects
   8. Persistent disk snapshots are available to all disks within the same project as the snapshot
   9. Optionally, users can share snapshots across projects
   10. An instance template can be used to create VM instances and managed instance groups
   11. An instance template is a global resource
   12. Zonal resources can be specified in an instance template, which restricts the use of that template to the location of the specified zonal resource
   13. A Cloud Interconnect is a highly available connection from an on-premises network to Google's network
   14. Interconnect attachments which run inside of this connection, are regional resources
   15. A Cloud Interconnect location is a physical connection point for Cloud Interconnect near the on premise network
   16. There is one Cloud Interconnect location for every available colocation facility and edge availability domain
   17. Cloud Interconnect locations are read-only, global resources
   18. A VPC network is a global resource, but individual subnets are regional resources
   19. Firewalls apply to a single VPC network and are considered a global resource because packets can reach them from other networks
   20. Routes are used to create complex networking scenarios
   21. Routes can be used to manage how traffic is routed for a specific IP range
   22. Routes are similar to how a router directs traffic within a local area network
   23. Routes apply to VPC networks within a Google Cloud project and are considered global resources
   24. Operations are a per-zone resource, a per-region resource, and a global resource
   25. If an operation is performed on a global resource, the operation is considered a global operation
   26. Operations are unique in that they span all three scopes: global resources, regional operations, and zonal operations
   27. A request to list operations returns operations across all three scopes
3. Regional
   1. Regional resources are accessible by any resources within the same region
   2. A static external IP address reserved in a specific region can only be assigned to instances within that region
   3. Each region also has one or more zones
   4. Addresses collection contains any regional static external IP addresses reserved for projects
   5. Static external IP addresses are a regional resource that are used by instances that are in the same region as the address, by regional forwarding rules for network load balancers, and for protocol forwarding
   6. An interconnect attachment allocates a VLAN on Cloud Interconnect and connects that VLAN to a VPC network
   7. An attachment is a regional resource, but a Cloud Interconnect connection is a global resource
   8. Subnets regionally segment the network IP space into prefixes (subnets) and control which prefix an instance's internal IP address is allocated from
   9. Regional managed instance groups are collections of identical instances that span multiple zones
   10. Regional managed instance groups spread app load across multiple zones, rather than confining app to a single zone or having to manage multiple instance groups across different zones
   11. Regional persistent disks provide durable storage and replication of data between two zones within the same region
   12. In a failover situation, force-attach a regional persistent disk to another instance within the same region
   13. Optionally, share disk resources across projects, to enable other projects make images and snapshots from these disks but doesn't let instances in other projects attach the disks
   14. Regional operations Operations are a per-zone resource, a per-region resource, and a global resource
   15. An operation on a regional resource is considered a per-region operation
   16. Reserving an address is considered a regional operation because addresses are a region-specific resource
4. Zonal
   1. Resources that are hosted in a zone are called per-zone resources
   2. Zone-specific resources, or per-zone resources, are unique to that zone and are only usable by other resources in the same zone
   3. An instance is a per-zone resource
   4. When an instance is created, the zone where the instance is located is provided
   5. Instances can access other resources within the same zone, and can access global resources, but can't access other per-zone resources in a different zone, such as a disk resource
   6. Instances in one zone can communicate with instances in another zone if both instances belong to the same VPC network
   7. A virtual machine (VM) instance is located within a zone and can access global resources or resources within the same zone
   8. Persistent disks are accessed by other instances within the same zone
   9. Users can attach a disk only to instances in the same zone as the disk
   10. Users can't attach a disk to an instance in another zone
   11. Optionally, users can share disk resources across projects, which lets other projects make images and snapshots from these disks but doesn't let instances in other projects attach the disks
   12. Machine types are per-zone resources
   13. Instances and disks can only use machine types that are in the same zone
   14. A zonal managed instance group uses an instance template to create a group of identical instances within a single zone
   15. VM instances are managed in a managed instance group as a single entity, rather than managing individual instances
   16. Operations are a per-zone resource, a per-region resource, and a global resource
   17. If you are performing an operation on a zone-specific resource, the operation is considered a per-zone operation
   18. Creating an instance is considered a per-zone operation because the operation is being performed on a zone-specific resource, an instance