LINBIT Introduces Container-Native Storage for Enterprise Applications

New Open-Source Software-Defined Storage Available for Kubernetes and OpenShift Environments.

“LINSTOR is designed to be container-native while consolidating storage and data management which saves time and money for IT departments,” said Brian Hellman, COO of LINBIT.

LINBIT, the de facto standard in open source High Availability (HA), Disaster Recovery (DR), Software-Defined Storage (SDS), and the force behind the renowned DRBD® open source software, today announced the public beta release of LINSTOR, a major new addition to its product portfolio. Serving the rapidly growing containerized applications market, LINSTOR fills a significant gap in the market by providing container-native block storage, a common data access model used by enterprise applications. LINSTOR can also provide data persistence for elastic applications, which dynamically create or remove containers depending on the load.

With LINSTOR, enterprise and database applications can benefit from container technologies while preserving data even when a container is eliminated; data centers can reduce cost and complexity when deploying scale-out cluster storage.

LINSTOR is part of LINBIT SDS, the industry’s fastest software defined storage solution for enterprise, cloud, and container environments. LINBIT SDS provisions, replicates, and manages data storage independent of hardware, thus enabling the use of commodity hardware and open source software, an important objective for many data centers. LINSTOR adds support for the popular Kubernetes and OpenShift environments.

LINBIT Introduces LINSTOR

“LINSTOR is designed to be container-native while consolidating storage and data management which saves time and money for IT departments,” said Brian Hellman, COO of LINBIT.

“Just as virtualization changed how storage must be configured and managed, container technologies demand a new approach,” said Brian Hellman, COO of LINBIT.

LINSTOR takes advantage of DRBD, a part of the Linux kernel for nearly a decade, to deliver fast and reliable data replication. By simplifying storage cluster configuration and ongoing management, then plugging into cloud and container front-ends, users get the resilient infrastructure they need while retaining flexibility to choose vendors. For example, using a pool of Linux storage, system administrators simply set the number of nodes, the number and size of storage volumes, and number of replicas, and LINSTOR identifies the servers with the proper space to build the environment.

“LINSTOR drastically simplifies storage provisioning and data replication without compromising speed and reliability,” said Philipp Reisner, CEO of LINBIT. “LINSTOR eliminates the long and complicated process of manually setting up cluster configuration files for each individual server.”

LINBIT will showcase its product portfolio with a special emphasis on container-native storage at the upcoming Red Hat Summit in San Francisco, California on May 8-10, 2018, Booth 432.

About LINBIT
LINBIT is the force behind DRBD and the de facto open standard for High Availability (HA) software for enterprise and cloud computing. The LINBIT DRBD software is deployed in millions of mission-critical environments worldwide to provide High Availability (HA), Geo Clustering for Disaster Recovery (DR), and Software Defined Storage (SDS) for OpenStack and OpenNebula based clouds.

Sebastian Schinhammer
Sebastian brings his experience in marketing to the table. As Marketing Manager at LINBIT he cares especially about content marketing, brand appearance and public relations. He fills brands with life telling engaging stories. Sebastian strives for his marketing efforts being helpful information or great entertainment rather than all bark but no bite.
Split brain

Split Brain? Never Again! A New Solution for an Old Problem: DRBD Quorum

While attending OpenStack Summit in Atlanta, I sat in a talk about the difficulties of implementing High Availability (HA) clusters. At one point, the speaker presented a picture of a split-brain, discussed the challenges in resolving them, and implementing STONITH in certain environments. As many of you know, “split-brain” is a condition that can happen when each node in a cluster thinks that it is the only active node. The system as a whole loses grip on its “state”; nodes can go rogue, and data sets can diverge without making it clear which one is primary. Data loss or data corruption can result, but there are ways to make sure this doesn’t happen, so I was interested in probing further.

Fencing is not always the solution

Split brain

The Split brain problem can be solved by DRBD Quorum.

To make it more interesting, it turned out that the speaker’s company uses DRBD and Pacemaker for HA, a setup that is very familiar to us. After the talk, I approached the speaker and recommended that they consider “fencing” as a way to avoid split-brain. Fencing regulates access to a shared resource and can be a good safeguard. As the resource needs separate communication path best practices suggest not using the same one that it is trying to regulate, so it needs a separate communication path. Unfortunately, in his environment, redundant networking was not possible. We needed another method.

Split brain is solved via DRBD Quorum

After talking to the speaker, it was clear to me that a new option for avoiding split brain or diverging data sets was needed since existing solutions may not always be feasible in certain infrastructures. This got me thinking about the various options for avoiding split-brain and how fencing could be implemented by using the built-in communication found in DRBD 9. It turns out that the capability of mirroring more than two nodes, found in DRBD 9 is a viable solution.

That idea sparked the work on the newest feature in DRBD: Quorum.

Shortly thereafter, the LINBIT team developed and integrated a working solution into DRBD. The code was pushed to the LINBIT repository and ready for testing.

Interest was almost immediate!

Later on, I happened to meet a few folks from IBM UK. They were working on IBM MQ Advanced Software, the well-known messaging middleware software that helps integrate applications and data across multiple platforms. They intended to use DRBD for their replication needs and quickly became interested in the idea of using a Quorum mechanism to mitigate split-brain situations.

DRBD Quorum takes new perspective

IBM LogoThe DRBD Quorum feature takes a new approach to avoiding data divergence.  A cluster partition may only modify the replicated data set if the number of nodes that can communicate is greater than half of the overall number of nodes within the defined cluster. By only allowing writes on a node that has access to over half the nodes in a given partition, we avoid creating a diverging data set.

The initial implementation of this feature would cause any node that lost Quorum (and was running the application/data set) to be rebooted.  Removing access to the data set is required to ensure the node stops modifying data. After extensive testing, the IBM team suggested a new idea that instead of rebooting the node, terminate the application. This action would then trigger the already available recovery process, forcing services to migrate to a node with Quorum!

Attractive alternative to fencing

As usual, the devil is in the details. Getting the implementation right with the appropriate resync decisions was not as straightforward as one might think. In addition to our own internal testing, many IBM engineers also tested it as well. We are happy to report that current implementation does exactly what was expected!

Bottom line:

If you need to mirror your data set three times, the new DRBD Quorum feature is an attractive alternative to hardware fencing.

In case you want to learn more about the Quorum implementation in DRBD
please see the DRBD9 user’s guide:
https://docs.linbit.com/docs/users-guide-9.0/#s-feature-quorum
https://docs.linbit.com/docs/users-guide-9.0/#s-configuring-quorum

Image  (Lloyd Fugde – stock.adobe.com)

Philipp Reisner on Linkedin
Philipp Reisner
Philipp Reisner is founder and CEO of LINBIT in Vienna/Austria. His professional career has been dominated by developing DRBD, a storage replication for Linux. Today he leads a company of about 30 employees with locations in Vienna/Austria and Portland/Oregon.

 

 

LINBIT’s DRBD ships with integration to VCS

The LINBIT DRBD software has been updated with an integration for Veritas Infoscale Availability (VIA). VIA, formerly known as Veritas Cluster Server (VCS), is a proprietary cluster manager for building highly available clusters on Linux. Examples of application cluster capabilities are Network File Sharing databases or e-commerce websites. VCS solves the same problem as the Pacemaker Open Source projects.  

Yet, in contrast to Pacemaker, VCS has a long history on the Unix Platform. VCS came to Linux as Linux began to surpass legacy Unix platforms. In addition to its longevity, VCS has a strong and clean user experience. For example, VCS is ahead of the Pacemaker software when it comes to clarity of log files. Notably, the Veritas Cluster Server has slightly fewer features than Pacemaker. (With great power comes complexity!)

Gear-drbd-integration-VCS

The gear runs even smoother. DRBD has an integration for VCS.

VCS integration for DRBD

Since January 2018, DRBD has been shipping with an integration to VCS. Users are now able to use VCS instead of Pacemaker and even control DRBD via VCS. It consists of two agents: DRBDConfigure and DRBDPrimary that enable drbd-8.4 and drbd-9.0 for VCS.

Full documentation can be found here on our website:

https://docs.linbit.com/docs/users-guide-9.0/#s-feature-VCS

and

https://github.com/LINBIT/drbd-utils/tree/master/scripts/VCS

Besides VCS Linbit DRBD supports variety of Linux software so you can keep your system up and running.

Besides VCS Linbit DRBD supports variety of Linux software so you can keep your system up and running.

Pacemaker 1.0.11 and up
Heartbeat 3.0.5 and up
Corosync 2.x and up

 

Reach out to [email protected] for more information.

We are driven by the passion of keeping the digital world running. That’s why hundreds of customers trust in our expertise, services and products. Our OpenSource product DRBD has been installed several million times. Linbit established DRBD® as the industry standard for High-Availability (HA) and data redundancy for mission critical systems. DRBD enables disaster recovery and HA for any application on Linux, including iSCSI, NFS, MySQL, Postgres, Oracle, Virtualization and more.

Philipp Reisner on Linkedin
Philipp Reisner
Philipp Reisner is founder and CEO of LINBIT in Vienna/Austria. His professional career has been dominated by developing DRBD, a storage replication for Linux. Today he leads a company of about 30 employees with locations in Vienna/Austria and Portland/Oregon.