Approached correctly, cloud migrations are a great opportunity to improve the security and stability of your applications. Many organizations are looking for guidance on how to meet their security requirements while moving at the speed that the cloud enables. They often try to configure everything perfectly in the data center before they migrate their first application. At AWS Managed Services (AMS), we’ve observed that successful migrations establish a secure foundation in the cloud landing zone then iterate from there. We think it’s important to establish a secure foundation in your cloud landing zone, and then refine and improve your security as you grow.

Customers who take a pragmatic, risk-based approach are able to innovate and move workloads more quickly to the cloud. The organizations that migrate fastest start by understanding the shared responsibility model. In the shared responsibility model, Amazon Web Services (AWS) takes responsibility for delivering security controls that might have been the responsibility of customers operating within their legacy data center. Customers can concentrate their activities on the security controls they remain responsible for. The modern security capabilities provided by AWS make this easier.

The most efficient way to migrate is to move workloads to the cloud as early as possible. After the workloads are moved, you can experiment with security upgrades and new security capabilities available in the cloud. This lets you migrate faster and consistently evolve your security approach. The sooner you focus on applying foundational security in the cloud, the sooner you can begin refining and getting comfortable with cloud security and making improvements to your existing workloads.

For example, we recently helped a customer migrate servers that weren’t sufficiently hardened to the Center for Internet Security (CIS) benchmarks. The customer could have attempted hardening on premises before their migration. That would have required spinning up dedicated infrastructure resources in their data center—a complex and costly, resource-intensive proposition.

Instead, we migrated their application to the cloud as it was, took snapshots of the servers, and ran the snapshots on an easy-to-deploy, low-cost instance of Amazon Elastic Compute Cloud (Amazon EC2). Using the snapshots, we ran scripts to harden those servers and brought their security scores up to over 90 percent against the CIS benchmarks.

Using this method to migrate let the customer migrate their existing system to the cloud quickly, then test hardening methods against the snapshots. If the application hadn’t run properly after hardening, the customer could have continued running on the legacy OS while fixing the issues at their own pace. Fortunately, the application ran seamlessly on the hardened snapshot of the OS. The customer switched to the hardened infrastructure without incurring downtime and with none of the risks or costs of trying to do it in their data center.

Migrations are great opportunities to uplift the security of your infrastructure and applications. It’s often more efficient to try migrating and break something rather than attempting to get everything right before starting. For example, dependence on legacy protocols, such as Server Message Block (SMB) v1, should be fixed by the customer or their migration partner as part of the initial migration. The same is true for servers missing required endpoint security agents. AWS Professional Services and AMS help customers identify these risks during migrations, and help them to isolate and mitigate them as an integral part of the migration.

The key is to set priorities appropriately. Reviewing control objectives early in the process is essential. Many on-premises data centers operate on security policies that are 20 years old or more. Legacy policies often clash with current security best practices, or lack the ability to take advantage of security capabilities that are native to the cloud. Mapping objectives to cloud capabilities can provide opportunities to meet or exceed existing security policies by using new controls and tools. It can also help identify what’s critical to fix right away.

In many cases, controls can be retired because cloud security makes them irrelevant. For example, in AMS, privileged credentials, such as Local Administrator and sudo passwords are either randomized or made unusable via policy. This removes the need to manage and control those types of credentials. Using AWS Directory Service for Microsoft Active Directory reduces the risk exposure of domain controllers for the resource forest and automates activities, such as patching, that would otherwise require privileged access. By using AWS Systems Manager to automate common operational tasks, 96 percent of our operations are performed via automation. This significantly reduced the need for humans to access infrastructure. This is one of the Well Architected design principles.

It’s also important to address the people and process aspects of security. Although the cloud can improve your security posture, you should implement current security best practices to help mitigate new risks that might emerge in the future. Migration is a great opportunity to refresh and practice your security response process, and take advantage of the increased agility and automation of security capabilities in the cloud. At AMS, we welcome every opportunity to simulate security events with our customers as part of a joint game day, allowing our teams to practice responding to security events together.

Or as John Brigden, Vice President of AMS, recently said in a blog post, “Traditional, centralized IT prioritized security and control over speed and flexibility. Outsourced IT could exacerbate this problem by adding layers of bureaucracy to the system. The predictable result was massive growth in shadow IT. Cloud-native, role-based solutions such as AWS Identity and Access Manager (IAM), Amazon CloudWatch, and AWS CloudTrail work together to enable enterprise governance and security with appropriate flexibility and control for users.”

In most cases, if it’s possible to migrate even a small application to the cloud early, it will be more efficient and less costly than waiting until all security issues have been addressed before migrating. To learn how using AMS to operate in the cloud can deliver a 243 percent return on investment, download the Forrester Total Economic Impact™ study.

You can use native AWS and third-party security services to inspect and harden your infrastructure. Most importantly, you can get a feel for security operations in the cloud—how things change, how they stay the same, and what is no longer a concern. When it comes to accelerating your migration securely, let the cloud do the heavy lifting.

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Stephen Bowie

Based in Seattle, Stephen leads the AMS Security team, a global team of engineers who live and breathe security, striving around the clock to keep our customers safe. Stephen’s 20-year career in security includes time with Deloitte, Microsoft, and Cutter & Buck. Outside of work, he is happiest sailing, travelling, or watching football with his family.