KB-1913 VM migration software and Appian

Parmida Borhani — Thu, 18 Mar 2021 01:39:46 GMT

Current Revision posted to Appian Knowledge Base by Parmida Borhani on 3/18/2021 1:39:46 AM

Purpose

The purpose of this article is to provide an understanding of how VM Migration Software, such as VMware VMotion, works and to answer some of the common questions related to using these softwares with Appian.

What is Live Migration?

Live migration refers to the process of moving a running virtual machine or application between different physical machines without disconnecting the client or application. Memory, storage, and network connectivity of the virtual machine are transferred from the original guest machine to the destination. One commonly used software for this is VMware VMotion.

VM Migration Software and Appian

Appian environments should not be hosted with any live VM migration software enabled because their capability has been known to cause problems with Kafka, a high performance component of Appian, as well as Zookeeper, which is a component it uses. The maintainers of Kafka state here that they recommend disabling VMotion for these components. As stated in our System Requirements documentation, this is a requirement while hosting Appian because these tools may cause data corruption, site unavailability or service degradation. VM migration can often create enough of a communications gap between Appian components that they detect a failure has occurred which can cause internal service metadata to be lost and trigger failover mechanisms.

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: March 2021

Tags: kafka, Vmotion, VM, zookeeper, Migration, infrastructure

KB-1913 VM migration software and Appian

Parmida Borhani — Thu, 18 Mar 2021 01:38:16 GMT

Revision 14 posted to Appian Knowledge Base by Parmida Borhani on 3/18/2021 1:38:16 AM

Purpose

What is Live Migration?

VM Migration Software and Appian

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: March 2021

Tags: zookeeper, Migration, infrastructure

KB-1913 VM migration software and Appian

Parmida Borhani — Wed, 17 Mar 2021 22:57:26 GMT

Revision 13 posted to Appian Knowledge Base by Parmida Borhani on 3/17/2021 10:57:26 PM

Purpose

What is Live Migration?

VM Migration Software and Appian

Appian environments should not be hosted with any live VM migration software because their capability has been known to cause inconsistencies between Appian components, such as Kafka and Zookeeper. This is a requirement while hosting Appian because these tools may cause data corruption, site unavailability or service degradation. VM migration can often create enough of a communications gap between Appian components that they detect a failure has occurred which can cause internal service metadata to be lost and trigger failover mechanisms.

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: March 2021

Tags: zookeeper, Migration, infrastructure

KB-1913 VM migration software and Appian

Parmida Borhani — Thu, 02 May 2019 02:19:34 GMT

Revision 12 posted to Appian Knowledge Base by Parmida Borhani on 5/2/2019 2:19:34 AM

Purpose

What is Live Migration?

VM Migration Software and Appian

Appian environments should not be hosted with any live VM migration software because their capability has been known to cause inconsistencies between Appian components. This is a requirement while hosting Appian because these tools may cause data corruption, site unavailability or service degradation. VM migration can often create enough of a communications gap between Appian components that they detect a failure has occurred which can cause internal service metadata to be lost and trigger failover mechanisms.

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: April 2019

Tags: zookeeper, Migration, infrastructure

KB-1913 VM Migration Software and Appian

Rebecca Jonas — Wed, 01 May 2019 14:27:00 GMT

Revision 11 posted to Appian Knowledge Base by Rebecca Jonas on 5/1/2019 2:27:00 PM

Purpose

What is Live Migration?

VM Migration Software and Appian

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: April 2019

Tags: zookeeper, Migration, infrastructure

KB-1913 VM Migration Software and Appian

Jordan Horwat — Tue, 16 Apr 2019 20:50:54 GMT

Revision 10 posted to Appian Knowledge Base by Jordan Horwat on 4/16/2019 8:50:54 PM

Purpose

What is Live Migration?

VM Migration Software and Appian

Appian does not recommend running your Appian environment with any live VM migration software because their capability has been known to cause inconsistencies between Appian components. This can lead to site unavailability or service degradation. This recommendation is because the VM migration process can often create enough of a communications gap between Appian components that they detect a failure has occurred, which can cause internal service metadata to be lost and trigger failover mechanisms.

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: April 2019

Tags: zookeeper, Migration, infrastructure

KB-1913 VM Migration Software and Appian

Jordan Horwat — Tue, 16 Apr 2019 20:50:35 GMT

Revision 9 posted to Appian Knowledge Base by Jordan Horwat on 4/16/2019 8:50:35 PM

Purpose

What is Live Migration?

VM Migration software and Appian

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: April 2019

Tags: zookeeper, Migration, infrastructure

KB-XXXX VM Migration Software and Appian

Tom Ryan — Mon, 15 Apr 2019 00:28:31 GMT

Revision 8 posted to Appian Knowledge Base by Tom Ryan on 4/15/2019 12:28:31 AM

Purpose

The purpose of this article is to provide an understanding of how VM Migration Software, such as VMware VMotion, works and answers to some of the common questions related to using those software with Appian.

What is Live Migration?

VM Migration software and Appian

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: April 2019

Tags: zookeeper, infrastructure

KB-XXXX VM Migration Software and Appian

Tom Ryan — Mon, 15 Apr 2019 00:27:43 GMT

Revision 7 posted to Appian Knowledge Base by Tom Ryan on 4/15/2019 12:27:43 AM

Purpose

What is Live Migration?

Live migration refers to the process of moving a running virtual machine or application between different physical machines without disconnecting the client or application. Memory, storage, and network connectivity of the virtual machine are transferred from the original guest machine to the destination. There are many software use to complete this process, one commonly used is VMware VMotion.

VM Migration software and Appian

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: April 2019

Tags: zookeeper, infrastructure

KB-XXXX VM Migration Software and Appian

Stephen Okala — Fri, 12 Apr 2019 17:49:30 GMT

Revision 6 posted to Appian Knowledge Base by Stephen Okala on 4/12/2019 5:49:30 PM

Purpose

What is Live Migration?

Live migration refers to the process of moving a running virtual machine or application between different physical machines without disconnecting the client or application. Memory, storage, and network connectivity of the virtual machine are transferred from the original guest machine to the destination. There are many software use to complete this process, one commonly used is VMware VMotion.

VM Migration software and Appian

Appian does not recommend running any live VM migration software in your Appian environment because their capability has been known to cause corruption inside Zookeeper. This can lead to site unavailability. Appian recommends disabling VMotion for any VMware severs that host Zookeeper. Appian's stance on this is:

"Zookeeper is very sensitive to latency. This is by design, since Zookeeper is in charge of coordinating state across the cluster. The migration process creates enough of a communications gap between the Zookeeper instances that they think a failure has occurred. Ephemeral data inside Zookeeper can be lost and if multiple Zookeeper nodes are migrated at the same time then they can lose quorum, which will cause that data to be lost. In addition, this blip in the Zookeeper cluster will almost assuredly cause Kafka/Service Manager to engage failover mechanism."

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: April 2019

Tags: zookeeper, infrastructure

INT-XXXX Handling questions customer have concerning VMware's VMotion and Appian

Jordan Horwat — Wed, 28 Nov 2018 14:57:32 GMT

Revision 5 posted to Appian Knowledge Base by Jordan Horwat on 11/28/2018 2:57:32 PM

Purpose

The purpose of this article is to provide Solution Engineers with an understanding of how VMware's VMotion works and answers to some of the common questions related to using VMware's VMotion with Appian.

What is VMotion?

VMware VMotion enables the live migration of running virtual machines from one physical server to another with zero downtime, continuous service availability, and complete transaction integrity. It is transparent to users.

VMotion lets you:

Automatically optimize and allocate entire pools of resources for maximum hardware utilization and availability.
Perform hardware maintenance without any scheduled downtime.
Proactively migrate virtual machines away from failing or underperforming servers.

VMotion and Appian

Appian does not recommend using VMotion because VMware's VMotion capability has been known to cause corruption inside Zookeeper, which can lead to site unavailability. Appian recommends disabling VMotion for any VMware severs that host Zookeeper. If the customer requests more detail regarding the corruption and what to watch out for, Engineering has provided us with the following:

"Zookeeper is very sensitive to latency. This is by design, since Zookeeper is in charge of coordinating state across the cluster. VMotion's migration process creates enough of a communications gap between the Zookeeper instances that they think a failure has occurred. Ephemeral data inside Zookeeper can be lost and if multiple Zookeeper nodes are migrated at the same time then they can lose quorum, which will cause that data to be lost. In addition, this blip in the Zookeeper cluster will almost assuredly cause Kafka/Service Manager to engage failover mechanism."

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: November 2018

Tags: zookeeper, infrastructure

INT-XXXX Handling questions customer have concerning VMware's VMotion and Appian

Stephen Okala — Wed, 28 Nov 2018 14:20:19 GMT

Revision 4 posted to Appian Knowledge Base by Stephen Okala on 11/28/2018 2:20:19 PM

Purpose

What is VMotion?

VMotion lets you:

Automatically optimize and allocate entire pools of resources for maximum hardware utilization and availability.
Perform hardware maintenance without any scheduled downtime.
Proactively migrate virtual machines away from failing or underperforming servers.

VMotion and Appian

Appian does not recommend using VMotion that is because VMware's VMotion capability has been known to cause corruption inside Zookeeper, which can lead to site unavailability. Appian recommends disabling VMotion for any VMware severs that host Zookeeper. If your customer wants more detail concerning what the corruption looks like and what to watch out for, Engineering has provided us with the following:

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: November 2018

Tags: zookeeper, FAQ

INT-XXXX VMware's VMotion and Appian

Stephen Okala — Wed, 28 Nov 2018 14:18:51 GMT

Revision 3 posted to Appian Knowledge Base by Stephen Okala on 11/28/2018 2:18:51 PM

Purpose

What is VMotion?

VMotion lets you:

Automatically optimize and allocate entire pools of resources for maximum hardware utilization and availability.
Perform hardware maintenance without any scheduled downtime.
Proactively migrate virtual machines away from failing or underperforming servers.

VMotion and Appian

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: November 2018

Tags: zookeeper, FAQ

INT-XXXX VMware's VMotion and Appian FAQ

Stephen Okala — Mon, 26 Nov 2018 23:11:22 GMT

Revision 1 posted to Appian Knowledge Base by Stephen Okala on 11/26/2018 11:11:22 PM

The purpose of this article is to provide answers to some of the common questions related to using VMware's VMotion with Appian.

Q: Does Appian recommend using VMware's VMotion ?

A: VMware's VMotion capability has been known to cause corruption inside Zookeeper, which can lead to site unavailability. Appian recommends disabling VMotion for any VMware severs that host Zookeeper.

Q: What does the corruption looks like? What to watch for?

A: Zookeeper is very sensitive to latency. This is by design, since ZK is in charge of coordinating state across the cluster. VMotion's migration process creates enough of a communications gap between the ZK instances that they think a failure has occurred. Ephemeral data inside ZK can be lost and if multiple ZK nodes are migrated at the same time then they can lose quorum, which will cause that data to be lost. In addition, this blip in the ZK cluster will almost assuredly cause Kafka/Service Manager to engage failover mechanism.

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: November 2018

Tags: zookeeper, FAQ

INT-XXXX VMware's VMotion and Appian FAQ

Stephen Okala — Mon, 26 Nov 2018 18:11:35 GMT

Revision 2 posted to Appian Knowledge Base by Stephen Okala on 11/26/2018 6:11:35 PM

The purpose of this article is to provide answers to some of the common questions related to using VMware's VMotion with Appian.

Q: Does Appian recommend using VMware's VMotion ?

Q: What does the corruption looks like? What to watch for?

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: November 2018

Tags: zookeeper, FAQ