A few weeks ago, the Linkerd service mesh achieved graduation status as a Cloud Native Computing Foundation (CNCF) project, joining the ranks of Kubernetes, Prometheus, Envoy and other CNCF cloud-native cornerstone projects.
In many ways, its acceptance serves as validation to its creators who sought to offer a less complex service mesh path to adoption that is accessible for DevOps teams that might not necessarily have the resources for Kubernetes deployments at the same scale as a Fortune 500 company.
“Linkerd’s niche is that it has a laser-focus on simplicity, especially operational simplicity, which is very unique in the service mesh world, which is mostly known for its complexity,” William Morgan, CEO of Buoyant and co-creator of Linkerd, told Container Journal. “This means that Linkerd’s community consists of engineers who want the power of the service mesh but don’t want to hire a team of people to actually operate it. Graduation is a reflection of the fact that this community is growing, inclusive and self-perpetuating.”
According to the most recent Cloud-Native Survey, 27% of organizations use a service mesh in production, a 50% increase over the previous year, and another 42% are evaluating or planning to use one. The CNCF says in a statement that “Linkerd has faced unprecedented competition in this rapidly-growing space,” but is not more specific about that competition.
In a statement, the CNCF notes that Linkerd is the foundation’s fifth project, its first service mesh project and the first CNCF project to use the Rust programming language to improve security and performance. Much of Linkerd’s popularity is owed to its reputation as a simpler-to-use service mesh geared for Kubernetes.
“Graduation is a public signal of maturity and of the self-sustaining nature of the project. With graduation, the CNCF now places Linkerd in the same category as Kubernetes, Prometheus, Envoy and other cloud-native stalwarts,” Morgan said. “Graduation is also, frankly, a bit of a vindication for Linkerd, which has faced down competitive projects marketed by companies with trillion-dollar market caps and shown that word-of-mouth adoption can still work for open source, even in the hype-driven world of the service mesh.”
For Chris Campbell, a staff developer for e-commerce platform provider Shopify, Linkerd serves as the lowest-cost solution available to meet necessary business requirements.
Cambell says Linkerd provided everything needed on his “list of things [I] care about” as a developer.
Standardized observability: Linkerd provides a “golden signal” SRE handbook for metrics via Prometheus and “real-time insights” with the dashboard and tap. “This is implemented at the infrastructure layer, which means our dev teams don’t need to do any integration—it works out of the box,” Campbell says.
Simple security: The service mesh uses mTLS with strong identity management via Linkerd and CertManager. “This is an easy thing to get wrong, so using a common framework is key. Again, this is implemented at the infrastructure layer, so apps don’t have to manage complexity,” Campbell says.
Multi-cluster support: “This gives us the ability to have redundant clusters which share, in effect, a flat network,” Campbell says. “This also gives us resiliency to Kubernetes cluster failures, but allows us to architect our apps as if there is one über cluster.”
Performance and reliability: Linkerd tends to “do the right thing” when it comes to managing traffic through your network and is thus optimized for latency. “You can configure timeouts and retries (with quotas to protect from retry storm) that improve tail error rates significantly—this can take you from 99.95% to 99.99% uptime, which can be significant in service-oriented architectures,” Campbell says.
Cost: There are four cost-saving factors here. First, since Linkerd is free and open source software (FOSS), no enterprise license is required. Second, low architectural complexity means less burden on operators to manage. And third, topology-aware routing “means savings on cloud network costs,” Campbell says. Fourth, the low compute requirements of the control plane and, “more importantly, the linkerd-proxy means big savings as you scale out,” Campbell says.
Trust: “The Linkerd maintainers are committed to open source and all that entails—not just hosting source code on GitHub. They build the project in the open, with public meetups, an end-user steering committee that is not filled with special interests and actively seek feedback and direction from the community,” Campbell says. “Also, the company, Buoyant, which employs most of the maintainers, is forthright about how they plan to monetize the technology.”