When organizations take their first steps to use public cloud services, they tend to look at a specific target.
My recommendation – think scale!
Plan a couple of steps ahead instead of looking at a single server that serves just a few customers. Think about a large environment comprised of hundreds or thousands of servers, serving 10,000 customers concurrently.
Planning will allow you to manage the environment (infrastructure, information security and budget) when you do reach a scale of thousands of concurrent customers. The more we plan the deployment of new environments in advance, according to their business purposes and required resources required for each environment, it will be easier to plan to scale up, while maintaining high level security, budget and change management control and more.
In this three-part blog series, we will review some of the most important topics that will help avoid mistakes while building new cloud environments for the first time.
Resource allocation planning
The first step in resources allocation planning is to decide how to divide resources based on an organizational structure (sales, HR, infrastructure, etc.) or based on environments (production, Dev, testing, etc.)
In-order to avoid mixing resources (or access rights) between various environments, the best practice is to separate the environments as follows:
- Share resource account (security products, auditing, billing management, etc.)
- Development environment account (consider creating separate account for test environment purposes)
- Production environment account
Separating different accounts or environments can be done using:
- Azure Subscriptions or Azure Resource Groups
- AWS Accounts
- GCP Projects
- Oracle Cloud Infrastructure Compartments
Even when deploying a single server inside a network environment (AWS VPC, Azure Resource Group, GCP VPC), it is important to tag resources. This allows identifying which resources belong to which projects / departments / environments, for billing purposes.
Common tagging examples:
- Environment (Prod, Dev, Test)
Beyond tagging, it is recommended to add a description to resources that support this kind of meta-data, in-order to locate resources by their target use.
Authentication, Authorization and Password Policy
In order to ease the management of working with accounts in the cloud (and in the future, multiple accounts according to the various environments), the best practice is to follow the rules below:
- Central authentication – In case the organization isn’t using Active Directory for central account management and access rights, the alternative is to use managed services such as AWS IAM, Google Cloud IAM, Azure AD, Oracle Cloud IAM, etc.
If managed IAM service is chosen, it is critical to set password policy according to the organization’s password policy (minimum password length, password complexity, password history, etc.)
- If the central directory service is used by the organization, it is recommended to connect and sync the managed IAM service in the cloud to the organizational center directory service on premise (federated authentication).
- It is crucial to protect privileged accounts in the cloud environment (such as AWS Root Account, Azure Global Admin, Azure Subscription Owner, GCP Project Owner, Oracle Cloud Service Administrator, etc.), among others, by limiting the use of privileged accounts to the minimum required, enforcing complex passwords, and password rotation every few months. This enables multi-factor authentication and auditing on privileged accounts, etc.
- Access to resources should be defined according to the least privilege principle.
- Access to resources should be set to groups instead of specific users.
- Access to resources should be based on roles in AWS, Azure, GCP, Oracle Cloud, etc.
It is important to enable auditing in all cloud environments, in-order to gain insights on access to resources, actions performed in the cloud environment and by whom. This is both security and change management reasons.
Common managed audit trail services:
- AWS CloudTrail – It is recommended to enable auditing on all regions and forward the audit logs to a central S3 bucket in a central AWS account (which will be accessible only for a limited amount of user accounts).
- Working with Azure, it is recommended to enable the use of Azure Monitor for the first phase, in-order to audit all access to resources and actions done inside the subscription. Later on, when the environment expands, you may consider using services such as Azure Security Center and Azure Sentinel for auditing purposes.
- Google Cloud Logging – It is recommended to enable auditing on all GCP projects and forward the audit logs to the central GCP project (which will be accessible only for a limited amount of user accounts).
- Oracle Cloud Infrastructure Audit service – It is recommended to enable auditing on all compartments and forward the audit logs to the Root compartment account (which will be accessible only for a limited amount of user accounts).
This series was originally posted on the GÉANT Cloud team web portal at https://clouds.geant.org/cloud-architecture/