This happened a little while ago, and the news about Rancher Labs has shifted to Suse’s announcement regarding its intent to acquire Rancher Labs. Nonetheless, I had a chance to speak to Sheng Liang (Co-founder and CEO) about Longhorn’s general availability, and thought I’d share some thoughts here.
What Is It?
Described by Rancher Labs as “an enterprise-grade, cloud-native container storage solution”, Longhorn has been in development for around 6 years, in beta for a year, and is now generally available. It’s comprised of around 40k lines of Golang code, and each volume is a set of independent micro-services, orchestrated by Kubernetes.
Liang described this to me as “enterprise-grade distributed block storage for K8S”, and the features certainly seem to line up with those expectations. There’s support for:
- Thin-provisioning, snapshots, backup, and restore
- Non-disruptive volume expansion
- Cross-cluster disaster recovery volume with defined RTO and RPO
- Live upgrade of Longhorn software without impacting running volumes
- Full-featured Kubernetes CLI integration and standalone UI
From a licensing perspective, Longhorn is free to download and use, and customers looking for support can purchase a premium support model with the same SLAs provided through Rancher Support Services. There are no licensing fees, and node-based subscription pricing keeps costs to a minimum.
Why would you use it?
- Bare metal workloads
- Edge persistent
- Geo-replicated storage for Amazon EKS
- Application backup and disaster recovery
One of the barriers to entry when moving from traditional infrastructure to cloud-native is that concepts seem slightly different to the comfortable slippers you may have been used to in enterprise infrastructure land. The neat thing about Longhorn is that it leverages a lot of the same concepts you’ll see in traditional storage deployments to deliver resilient and scalable persistent storage for Kubernetes.
This doesn’t mean that Rancher Labs is trying to compete with traditional storage vendors like Pure Storage and NetApp when it comes to delivering persistent storage for cloud workloads. Liang acknowledges that these shops can offer more storage features than Longhorn can. There seems to be nonetheless a requirement for this kind of accessible and robust solution. Plus it’s 100% open source.
Rancher Labs already has a good story to tell when it comes to making Kubernetes management a whole lot simpler. The addition of Longhorn simply improves that story further. If you’re feeling curious about Longhorn and would like to know more, this website has a lot of useful information.