Zerto provides disaster recovery for containerised apps

Zerto is branching out from disaster recovery of virtual machines to offer general backup services. The company will also cover cloud-native applications with its continuous data protection (CDP) and journalling technology.

The company announced the plans, along with a roadmap for its IT Resilience Platform, today at the ZertoCON virtual customer conference.

Specifically, Zerto has announced Zerto for Kubernetes (Z4K – our acronym) to protect applications running on Amazon Elastic Kubernetes Service (Amazon EKS), Google Kubernetes Engine (GKE), Microsoft Azure Kubernetes Service (AKS), Red Hat OpenShift, and VMware Tanzu.

Gil Levonai.

Zerto’s Gil Levonai, CMO and SVP of product, said in prepared remarks: “With the clear shift towards containers based application development in the market, we are looking to extend our platform to offer these applications the same level of resilience we have delivered to VM-based applications.

“While next-gen applications are built with a lot of internal availability and resilience concepts, they still require an easy and simple way to recover from human error or malicious attacks, or to be mobilised and recovered quickly without interruption. This is where Zerto can help.”

Zerto for Kubernetes

Z4K protects persistent data and can protect, move and recover containerised applications as one consistent entity, including associated Kubernetes objects and metadata. It features continuous journaling for Kubernetes apps, including Persistent Volumes, StatefulSets, Deployments, Services, and ConfigMaps. This journal can provide thousands of recovery checkpoints.

It has always-on replication to provide protection and recovery of Kubernetes persistent volumes within and between clusters, data centres or clouds.

Entire applications with their component containers can be recovered as entities in an ordered way. Z4K can instantiate a full running copy of an entire application in minutes from any point in time for recovery from data corruption or ransomware without impacting production or for testing.

There are automated Z4K workflows for failover, failover test, restore, rollback restore, and commit restore. The Z4K software is managed through a kubectl plug-in and native Kubernetes tooling.

Competitive positioning

Z4K is not provisioning storage to containers – unlike Kasten and Portworx which also offer  containerised application protection. Deepak Verma, Director, Product Strategy at Zerto, told Blocks & Files it runs as a native K8s application which provides CDP-based journaling for persistent volumes running on the cluster nodes plus the backup, restore, and DR orchestration necessary to execute any desired use cases for resilience of K8s applications.

Verma said: “Kasten, judging from public documentation, appears to be relying the snapshot mechanism of the cloud platforms to capture data, with a minimum timeframe of five mins. Zerto for K8s on the other hand is providing CDP for persistent volumes at a 5-10 second interval and capturing all the necessary attributes of a K8s application in a consistency group to recreate locally or remotely down to a very granular point in time.”

In summary, Z4K has “less complexity and vendor lock-in than Portworx and more granular RPOs and having point-in-time consistency across multiple containers compared with Kasten”.

CPU load

Blocks & Files pictures a Kubernetes system executing thousands of containers over a few hours. Z4K is app-aware and so the host server has to run these containers and also do the granular continuous journaling for Z4K, with its thousands of checkpoints. We asked Zerto what is the burden on the host server processors of this additional load?

Verma said: “Zerto for K8s is built upon the same core journaling and CDP technology and intellectual property that Zerto has successfully deployed and improved for the last 10 years in very large VM environments.

“The relative overhead for most environments has been less than 10 per cent CPU and memory at the host level during busy times of high change rate. The predictable scaling of which is very well understood as well. Since we are still at the alpha stage, we have not run extensive performance tests, but do not expect the technology to be much different than what we currently utilise as guidelines.

“Part of the success of Zerto has been its very efficient CDP mechanism. For production application we view this as a minor overhead to provide the level of RPOs and RTOs that customers have come to expect from Zerto.”

Z4K will be available in an early adopter program later in 2020 and goes on general release next year.


Zerto said it is decoupling operational recovery from backup because continuous journaling eliminates the need for snapshot-based backup. 

Levonai said: “Historically, top-tier, customer-facing applications would be protected with multiple data protection and disaster recovery solutions while lower-tier applications would be protected with high RPO backups only, or not protected at all. Zerto is levelling the playing field by applying its CDP technology to each of these … applications, transforming the backup market.”

The company plans to extend its IT Resilience Platform with a mix of one-to-many replication, local and remote journaling, long-term repositories, and short-term and long-term retention policies. The aim is meet various SLA needs at various cost levels.

The company will offer in-cloud protection and DR for AWS, Azure and GCP. There will be tiering to cloud object stores, with built-in data reduction technology, for long-term retention.

Zerto will develop new workflows to simplify file or VM restores back to production from a local or remote journal. Additional roadmap features include added VM auto-protection, encryption and security, automatic VRA lifecycle management for maintenance, features for managed service providers, new analytics functionality and an improved licensing mechanism.