In this section:
The AWS provides High Availability through the use of Elastic IP (EIP). With EIP, when a switchover from an active SBC instance to a standby instance is required, the IP address for the active server moves to the standby instance through a REST API call, which can result in a 15-20 second switchover time. While this solution may be acceptable for the majority of web-based applications, it does not meet the requirements needed for SBCs for real-time communications.
To accomplish switchover times closer to 2 seconds, an HA Front-End (HFE) was added to the AWS architecture solution to host the Elastic IP.
The SBC SWe does not support IPsec in AWS.
The High-Availability Front End (HFE) front-ends only one pkt port (pkt0), public endpoints can be connected only to pkt0. Pkt1 can serve private endpoints.
The HFE is configured using a script named "HFE.sh". This script is available in addition to example CloudFormation templates which support the deployment of an HA SBC with HFE.
Both files are required to deploy an SBC with High-Availability Front-End.
If you delete an instance from the CFN, be aware that AWS does not delete volume(s) automatically. You must also delete them from the AWS UI if you do not want volumes of deleted instances (standalone, HA or HFE-based SBC installation).
Prerequisites for AWS CFN Install of HFE and SBC HA Instance with Automated HFE Private Subnet Creation
Prior to initiating a CFN-based install of an HA SBC instance with HFE perform the following:
- Download the CFN supporting HFE and the HFE configuration script (HFE.sh) to your desktop.
- Create a VPC for use in the deployment. Refer to Create a VPC for the SBC SWe.
- Create Internet Gateway for use in the deployment. Refer to Create an Internet Gateway for SBC SWe.
- Create Key Pairs for Linux shell access and Administrator access. Refer to Create Key Pairs for the SBC SWe.
- Create Subnets for use in the deployment - HFE Public, SBC Management, SBC HA0, SBC PKT0, SBC PKT1. Refer to Create Subnets for the SBC SWe.
- Ensure space in VPC exists and determine subnet CIDR to use to create a new HFE Subnet (which is done by this CFN).
- Create Security Groups for use in the deployment. Refer to Create Security Groups for SBC SWe.
- Update or create Route tables for the newly created subnets. Refer to Create Route Tables for SBC SWe.
- Create a placement group for the SBC deployment. Refer to Create Placement Groups.
- Create a Policy and Role for the SBC instance. Refer to Create an Identity and Access Management (IAM) Role for SBC SWe.
- Create and Upload the HFE.sh script to S3 bucket. Refer to Upload HFE.sh script to S3.
- Create a Policy and Role for the HFE instance. Refer to Create an Identity and Access Management (IAM) Role for HFE.
- Locate the AMI ID in your region for an Amazon Linux 2 image. Refer to Locate Amazon Linux 2 AMI ID for use in HFE Deployments.
Instantiate an HFE and HA SBC Instance
To instantiate a standalone instance:
Log onto AWS.
Click the Services drop-down list.
The Services list is displayed.Click CloudFormation from Management Tools section.
Click Create Stack. The Select Template page displays.
- In the Choose a template section, select Upload a template to Amazon S3.
- Click Choose File to navigate through the folders and select the template.
Click Next.
The Create A New Stack page displays.NoteIf you desire to use pre-allocated EIPs for management, ensure you to set EIPAssociationForMgt to "No" at the field prompt.
After the deployment has completed, you must manually associate the pre-allocated EIP to Mgmt (Eth0) Primary and secondary IPs.
In the Stack name field enter a unique name for this SBC stack. A stack is a collection of AWS resources you create and delete as a single unit.
Enter the required values for the Parameter fields. The following table describes the create stack parameters:
NoteThird party CPU setting of more than two vCPU is not supported with p3.2xlarge instances due to the vCPU requirement of the Standard_GPU_Profile.
- Click Next.
The Options page displays. Optionally you can choose to Tag your deployment with a Key-value pair, IAM Role Permissions, Rollback Triggers or other advanced Options.
- Click Next.
The Review page displays. - Review the stack details and click Create
The CloudFormation Stacks page is displayed. - On successful stack creation, the stack then lists.
Do not update or modify the stack after creation.
Do not change or remove resources after instance creation. For example, removing or attaching EIP, or changing the user data.
Verify the Instance Creation
Perform the following steps to view the SBC SWe instances created:
Click the Services drop-down list.
The Services list is displayed.From the left pane click EC2.
The EC2 Dashboard page is displayed.
From the left pane under Instances click Instances.
The instances table lists the new instance.CautionIf you delete an instance from CFN, be aware that AWS does not delete volume(s) automatically. You must also delete it from the AWS UI if you do not want volumes of deleted instances (standalone, HA or HFE-based SBC installation).