GreyBeards on Storage

GreyBeards on Storage


126: GreyBeards talk k8s storage with Alex Chircop, CEO, Ondat

December 07, 2021

Keith and I had an interesting discussion with Alex Chircop (@chira001), CEO of Ondat, a kubernetes storage provider. They have a high performing system, laser focused on providing storage for k8s stateful container applications. Their storage is entirely containerized and has a number of advanced features for data availability, performance and security that developers need the run stateful container apps. Listen to the podcast to learn more.



Ondat-21-12-transcriptDownload

We started by asking Alex how Ondats different from all the other k8s storage solutions out there today (which we’ve been talking with lately). He mentioned three crucial capabilities:



  • Ondat was developed from the ground up to run as k8s containers. Doing this would allow any k8s distribution to run their storage to support stateful container apps. .
  • Ondat was designed to allow developers to run any possible container app. Ondat supports both block as well as file storage volumes.
  • Ondat provides consistent, superior performance, at scale, with no compromises. Sophisticated data placement insures that data is located where it is consumed and their highly optimized data path provides low-latency access that data storage.

Ondat creates a data mesh (storage pool) out of all storage cluster nodes. Container volumes are carved out of this data mesh and at creation time, data and the apps that use them are co-located on the same cluster nodes.



At volume creation, Dev can specify the number of replicas (mirrors) to be maintained by the system. Alex mentioned that Ondat uses synchronous replication between replica clusters nodes to make sure that all active replica’s are up to date with the last IO that occurred to primary storage.



Ondat compresses all data that goes over the network as well as encrypts data in flight. Dev can easily specify that the data-at-rest also be compressed and/or encrypted. Compressing data in flight helps supply consistent performance where networks are shared.



Alex also mentioned that they support both the 1 reader/writer, k8s block storage volumes as well as multi-reader/multi-writer, k8s file storage volumes for containers.



In Ondat each storage volume includes a mini-brain used to determine primary and replica data placement. Ondat also uses desegregated consensus to decide what happens to primary and replica data after a k8s split cluster occurs. After a split cluster, isolated replica’s are invalidated and replicas are recreate, where possible, in the surviving nodes of the cluster portion that holds the primary copy of the data.



Also replica’s can optionally be located across AZs if available in your k8s cluster. Ondat doesn’t currentlysupport replication across k8s clusters.



Ondat storage works on any hyperscaler k8s solution as well as any onprem k8s system. I asked if Ondat supports VMware TKG and Alex said yes but when pushed mentioned that they have not tested it yet.



Keith asked what happens when things go south, i.e., an application starts to suffer worse performance. Alex said that Ondat supplies system telemetry to k8s logging systems which can be used to understand what’s going on. But he also mentioned they are working on a cloud based, Management-aaS offering, to provide multi-cluster operational views of Ondat storage in operation to help understand, isolate and fix problems like this.



Keith mentioned he had attended a talk by Google engineers that developed kubernetes and they said stateful containers don’t belong under kubernetes. So why are stateful containers becoming so ubiquitous now.



Alex said that may have been the case originally but k8s has come a long way from then and nowadays as many enterprises shift left enterprise applications from their old system environment to run as containers they all require state for processing. Having that stateful information or storage volumes accessible directly under k8s makes application re-implementation much easier.



What’s a typical Ondat configuration? Alex said there doesn’t appear to be one. Current Ondat deployments range from a few 100 to 1000s of k8s cluster nodes and 10 to 100s of TB of usable data storage.



Ondat has a simple pricing model, licensing costs are determined by the number of nodes in your k8s cluster. There’s different node pricing depending on deployment options but other than that it’s pretty straightforward.



Alex Chircop, CEO Ondat

Alex Chircop is the founder and CEO of Ondat (formerly StorageOS), which makes it possible to easily deploy and manage stateful Kubernetes applications with persistent data volumes. He also serves as co-chair of the CNCF (Cloud Native Computing Foundation) Storage Technical Advisory Group.



Alex comes from a technical background working in IT that includes more than 10 years with Nomura and Goldman Sachs.