On-Premises Prerequisites

Before installing Chef automate HA in On-premises deployment mode, ensure you have taken a quick tour of this prerequisite page.

Chef Automate Architecture

We recommend using 11 node cluster for standard Automate HA on-premises deployment, as detailed in the table below:

Additionally, this topology requires two load balancers and 2 DNS entries with certificates. Refer to the architectural page for further guidance.

We recommend using Chef Infra Server managed by Automate HA to have high availability for both Automate and Infra Server. External Standalone Infra Server will violate this high availability requirement.

Software Requirements

The software requirements of the nodes in the cluster and other external Chef and non Chef tools are discussed below:

Node Software Requirements

The operating system and the supported version for different nodes in the on-premises deployment of Automate HA are mentioned below:

Minimum Supported Chef Tool Versions

Current Automate HA supports integration with the following Chef tools:

• Chef Infra Server version: 14.0.58+
• Chef Inspec version: 4.3.2+
• Chef Infra Client: 17.0.242+
• Chef Habitat: 0.81+

We do not support Chef Manage and Supermarket integration in the ongoing Automate version.

External Supported Softwares

Current Automate HA integrates with the following non-Chef tools:

• SQL Database: PostgreSQL: 13.5
• NoSQL Database: OpenSearch: 1.3.7
• Load Balancer: NGINX: 1.21.3 or HA Proxy: 2.2.18 or AWS Application Load Balancer

Hardware Requirements

We have some sample values based on the performance benchmarking tests to give you an apt hardware configuration. Refer to the table below to populate things in the Hardware Calculator according to your requirement. The table below shows the tested assumptions and should not be used as exact recommendations.

You can use the below assumptions in the calculator to drive into your hardware requirement:

The machine requirements based on the above assumptions are listed below:

Load Balancer

Load Balancers in on-premises deployment need to be set up according to Chef Automate HA Architecture.

You can set up your load balancer using:

• NGINX 1.21.3
• HA Proxy 2.2.18
• AWS Application Load Balancer

Firewall Checks

The Chef Automate HA cluster requires multiple ports for the frontend and backend servers to operate effectively.

The first column in the table below represents the source of the connection. The table’s other columns represent the destination with the matrix value as a port number. The specified port numbers need to be opened on the origin and destination.

Port usage definitions

Certificates

Generate the certificates using recommended tools and supported algorithms and versions mentioned below:

• OpenSSL: 1.0.2zb-fips
• OpenSSL Algorithms: PBE-SHA1-3DES, RSA (2048), SHA-256
• Certificate Format: X509 V3(PEM format) ,Private key is in PKCS8 format

To understand how to generate certificates, refer to the Certificate Generation documentation.

Deployment Specific Pre-requisites

The on-premises deployment specific pre-requisites are as follows:

Infra Server

• Chef Automate HA comes with bundled Infra Server, and it is recommended not to use any external server in Automate HA. Using an external server will lose the Automate HA functionalities, and things may not work as expected.

Access

• All Virtual Machines or Machines should be up and running.
• We need a local user hab and local group hab linked together to complete the deployment process successfully.
• If they are unavailable, the SSH user should have privileges to create local users and groups so that the deployment process can create the required local user hab and local group hab.
• Currently we only support local Linux users and groups for Installation flow. We don’t support AD or LDAP managed users in nodes.
• The SElinux config should either be disabled or permissive.

Storage Space

• Operating System Root Volume (/) must be at least 40GB. Temporary space (/var/tmp) must be at least 5GB.
• Separate Hab volume should be provisioned and mounted at /hab with at least 100GB free space for all nodes except OpenSearch.
• For OpenSearch nodes, /hab volume should be calculated based on the data retention policy, and use the hardware calculator for estimation.

SSH User

• SSH users should use key-based SSH login without a passphrase.
• The user’s SSH key should be generated using algorithms ed25519 and RSA(2048) without a passphrase.
• This SSH user should be a local Linux user on all the machines.
• This SSH user should have sudo privileges on all the machines.
• The SSH user should access all machines using the same SSH private key.

Cluster Setup

• LoadBalancers should be set up according to Chef Automate HA Architecture.
• Network ports should be opened as per Chef Automate HA Architecture needs as explained in Security and Firewall page.
• DNS is configured to redirect chefautomate.example.com to the Primary Load Balancer.
• DNS is configured to redirect chefinfraserver.example.com to the Primary Load Balancer.
• Domain Certificates should be created and added for chefautomate.example.com, and chefinfraserver.example.com in the Load Balancers.
• We expect the customer to have all the Cluster related items ready before deployment. Customer experts will set up things like Load Balancer, Ports, and DNS with certificates.

Config Changes

• Config Patch in the whole application will result in downtime. For example, if you change or update something in OpenSearch or PostgreSQL, they will restart, resulting in restarting everything.
• Certificate Rotation will also change the system’s configuration, leading to restarting the whole application.

To learn more about the above deployment, visit our on-premises deployment page.

External Managed Databases

Set up the databases with password-based authentication.

AWS Managed

• AWS RDS PostgreSQL: 13.5
• AWS OpenSearch: 1.3

Configure the backup only with S3 when using AWS managed databases.

Customer Managed

• PostgreSQL: 13.5
• OpenSearch: 1.3.7

Upgrade

Things to keep in mind while upgrading are:

• Backend upgrades will restart the backend service, which takes time for the cluster to be healthy.
• Upgrade command currently supports only minor upgrades.
• A downtime will occur while upgrading the frontend, backend or the workspace.
• Rolling upgrades are not supported.

Disaster Recovery

Chef Automate HA supports disaster recovery in active/passive mode. The primary cluster will be in active mode, and the disaster recovery cluster will be in passive mode.

Active/Active Disaster Recovery is not supported right now as we do not support streaming of data across clusters and automatic failover switching of clusters.

The requirements for disaster recovery setup (Active/Passive) are:

• Two identical clusters located in different data centers or cloud provider regions.
• Network Attached Storage (NAS) or Object Store (S3) should be available in both data centers/regions.
• Set up scheduled jobs to run backup and restore commands on both clusters. We recommend using cron to schedule the jobs.

To know more about the on-premises deployment disaster recovery, visit our Disaster Recovery Setup page.

Migration

Common Notes

• Migrations involve downtime depending on how much data you have and the type of setup you are running.

• Migration cannot be done from more than 1 Standalone Automate, more than 1 Standalone Infra Server, or more than 1 Chef Backend to a Single Automate HA cluster.

• Automate HA will always have Chef Automate and Chef Infra Server running in the cluster.

• Chef Manage or Private Chef Supermarket customers should not migrate to Automate HA.

Backup and Restore

In On-premises deployment of Automate HA, we support Network File System (NFS) or Object Storage (S3/MinIO) for taking backup.

Encrypted S3 bucket are supported with only Amazon S3 managed keys (SSE-S3).