ODB Network Design
Learn about Oracle Database@AWS's ODB Network requirements and find reference information for network design.
An ODB network is a private and isolated network that hosts the Oracle Exadata VM Clusters and Autonomous VM Clusters within a specified AWS Availability Zone (AZ). The ODB network consists of a CIDR range of IP addresses. The ODB network maps directly to the network that exists within the Oracle Cloud Infrastructure (OCI) child site, thus serving as the means of communication between AWS and OCI. In Oracle Multicloud architecture, the ODB network is designed to accommodate and provide network connectivity for the OCI components that are part of Oracle Database@AWS.
The ODB network is a private network, and by default, doesn't have connectivity to AWS VPCs, on-premises networks or the internet. ODB peering is a user-created network connection that enables traffic to be routed privately between an Amazon VPC and an ODB network. In Oracle Multicloud architecture, traffic between your applications in the VPC and the Oracle Database in the ODB network is routed privately through ODB Peering without moving over the public internet.
The ODB network requires a client subnet CIDR for Exadata VM Cluster and Autonomous VM Cluster creation. The network also requires a backup subnet CIDR for Exadata VM Cluster creation to route the traffic for Oracle-managed backups from Exadata Database Service to the backup destination.
The following section describes the CIDR requirements and planning required when creating the ODB network.
Client subnet CIDR requirements
The minimum CIDR size for the client subnet is /27, and the maximum size is /16. The following table shows IP addresses consumed by the Oracle Database@AWS service and the infrastructure components for the client subnet CIDR:
| Number of IP addresses | Consumed by | Summary |
|---|---|---|
| 6 | Oracle Database@AWS | These IP addresses are reserved regardless of how many VM clusters you provision in the ODB network. Oracle Database@AWS consumes the following:
|
| 3 | Each VM cluster | These IP addresses are reserved for Single Client Access Names (SCANs) regardless of how many VMs are present in each VM cluster. |
| 4 | Each VM | Each VM created consumes 4 IP addresses. |
Backup subnet CIDR requirements
The minimum CIDR size for the backup subnet is /28, and the maximum size is /16. The following table shows IP addresses consumed by the Oracle Database@AWS service and the infrastructure components for the backup subnet CIDR:
| Number of IP addresses | Consumed by | Summary |
|---|---|---|
| 3 | Oracle Database@AWS | These IP addresses are reserved regardless of how many VM clusters you provision in the ODB network. Oracle Database@AWS consumes the following:
|
| 3 | Each VM | Each VM created consumes 3 IP addresses. |
IP consumption scenarios
The following table explains how IP addresses are consumed in the ODB network for various VM clusters configurations. Though /28 is the minimum CIDR range for the client subnet CIDR to deploy 1 VM cluster with 2 VMs, Oracle recommends that you use at least a /27 CIDR range.
| Configuration | Client subnet IPs consumed | Client subnet minimum CIDR | Backup subnet IPs consumed | Backup subnet minimum CIDR |
|---|---|---|---|---|
| 1 VM cluster with 2 VMs | 17 (6 service + 3 cluster + 4*2) | /27 CIDR range, 32 IPs | 9 (3 service + 3*2) | /28 CIDR range, 16 IPs |
| 1 VM cluster with 3 VMs | 21 (6 service + 3 cluster + 4*3) | /27 CIDR range, 32 IPs | 12 (3 service + 3*3) | /28 CIDR range, 16 IPs |
| 1 VM cluster with 4 VMs | 25 (6 service + 3 cluster + 4*4) | /27 CIDR range, 32 IPs | 15 (3 service + 3*4) | /28 CIDR range, 16 IPs |
| 1 VM cluster with 8 VMs | 41 (6 service + 3 cluster + 4*8) | /26 CIDR range, 64 IPs | 27 (3 service + 3*8) | /27 CIDR range, 32 IPs |
VM Cluster Scenarios: Client Subnet CIDR
The following table shows how many instances of each configuration are possible with a particular client subnet CIDR range. This table doesn't show all possible scenarios.
| Scenario (VM Cluster configuration) | Number of VM Clusters with /27 (32 IPs) | Number of VM Clusters with /26 (64 IPs) | Number of VM Clusters with /25 (128 IPs) | Number of VM Clusters with /24 (256 IPs) | Number of VM Clusters with /23 (512 IPs) | Number of VM Clusters with /22 (1024 IPs) |
|---|---|---|---|---|---|---|
| 1 VM Cluster with 2 VMs (16 IPs) | 1 | 3 | 7 | 15 | 30 | 60 |
| 1 VM Cluster with 3 VMs(20 IPs) | 1 | 3 | 6 | 12 | 24 | 48 |
| 1 VM Cluster with 4 VMs(24 IPs) | 1 | 2 | 5 | 10 | 20 | 40 |
| 2 VM Cluster with 2 VMseach (27 IPs) | 1 | 2 | 4 | 9 | 18 | 36 |
| 2 VM Cluster with 3 VMseach (35 IPs) | 0 | 1 | 3 | 7 | 14 | 28 |
| 2 VM Cluster with 4 VMseach (43 IPs) | 0 | 1 | 2 | 5 | 11 | 23 |
VM Cluster Scenarios: Backup Subnet CIDR
The following table shows how many instances of each configuration are possible with a particular backup subnet CIDR range. This table doesn't show all possible scenarios.
| Scenario (VM Cluster configuration) | Number of VM Clusters with /27 (32 IPs) | Number of VM Clusters with /26 (64 IPs) | Number of VM Clusters with /25 (128 IPs) | Number of VM Clusters with /24 (256 IPs) | Number of VM Clusters with /23 (512 IPs) | Number of VM Clusters with /22 (1024 IPs) |
|---|---|---|---|---|---|---|
| 1 VM Cluster with 2 VMs (9 IPs) | 3 | 7 | 14 | 28 | 56 | 113 |
| 1 VM Cluster with 3 VMs (12 IPs) | 2 | 5 | 10 | 21 | 42 | 85 |
| 1 VM Cluster with 4 VMs (15 IPs) | 2 | 4 | 8 | 17 | 34 | 68 |
| 2 VM Cluster with 2 VMs each (15 IPs) | 2 | 4 | 8 | 17 | 34 | 68 |
| 2 VM Cluster with 3 VMs each (21 IPs) | 1 | 3 | 6 | 12 | 24 | 48 |
| 2 VM Cluster with 4 VMs each (27 IPs) | 1 | 2 | 7 | 9 | 18 | 37 |
Restrictions for IP Addresses
The following restrictions apply for the CIDR range of the ODB network subnets:
- Valid private IPv4 CIDR ranges required: The CIDR block must be private and IPv4. For example, 10.0.0.0/16, 172.16.0.0/16, 192.168.1.0/26.
-
Restricted CIDR blocks
The following IP addresses can't be used for an ODB network:
- 100.64.0.0/10 - Reserved for the cluster interconnect by OCI automation
- 100.105.0.0/16 - Reserved for local storage interconnect
- 169.254.0.0/16 - Oracle Cloud reserved range CIDR
- 224.0.0.0 - 239.255.255.255 - Reserved Class D
- 240.0.0.0 - 255.255.255.255 - Reserved Class E
- Restricted associations: You can't use the VPC CIDR ranges in the Restricted associations column in the table in IPv4 CIDR block association restrictions.
- You can't overlap the IP address CIDR ranges of the client subnets and backup subnets.
- You can't overlap the IP address CIDR ranges of the client and backup subnets with the VPC CIDR ranges used to connect to the ODB network.
- You can't overlap the IP address CIDR ranges of the client and backup subnets with any of the existing VPC CIDR ranges in a region for the "buyer" or "owner" AWS Account. See AWS Account for details on these account types.