Amazon’s Elastic Kubernetes Service (EKS) now supports IPv6 address spaces according to a new blog post by Sébastien Stormacq, principal developer advocate, AWS.
Amazon EKS is said to makes it easy to deploy containerised workloads. It provides highly available clusters and automates tasks such as patching, node provisioning, and updates.
Kubernetes presents network management challenges, he explained.
Kubernetes uses a flat networking model that requires each pod to receive an IP address. This simplified approach enables low-friction porting of applications from virtual machines to containers but requires a significant number of IP addresses that many private VPC IPv4 networks are not equipped to handle.
Some cluster administrators work around this IPv4 space limitation by installing container network plugins (CNI) that virtualize IP addresses a layer above the VPC, but this architecture limits an administrator’s ability to effectively observe and troubleshoot applications and has a negative impact on network performance at scale. Further, to communicate with internet services outside the VPC, traffic from IPv4 pods is routed through multiple network hops before reaching its destination, which adds latency and puts a strain on network engineering teams who need to maintain complex routing setups.
To avoid IP address exhaustion, minimize latency at scale, and simplify routing configuration, the solution is to use IPv6 address space.
There are a few advantages to using Amazon EKS clusters with an IPv6 network, Stormacq lists a few.
“First, you can run more pods on one single host or subnet without the risk of exhausting all available IPv4 addresses available in your VPC. Second, it allows for lower-latency communications with other IPv6 services, running on-premises, on AWS, or on the internet, by avoiding an extra NAT hop. Third, it relieves network engineers of the burden of maintaining complex routing configurations.”
He also pointed out that Kubernetes cluster administrators can focus on migrating and scaling applications without spending efforts working around IPv4 limits. Finally, pod networking is configured so that the pods can communicate with IPv4-based applications outside the cluster, allowing to adopt the benefits of IPv6 on Amazon EKS without requiring that all dependent services deployed across your organisation are first migrated to IPv6.