How to Fix vSAN Cluster Errors After Removing a Host and Disk Groups

Learn how to troubleshoot and resolve vSAN cluster errors that may occur after removing a host and disk groups from a vSAN cluster.

vSAN is a software-defined storage solution that allows you to create a shared datastore from local disks of the hosts in a vSphere cluster. vSAN provides high availability, scalability, and performance for your virtual machines.

However, vSAN cluster configuration can be complex and sensitive, and sometimes you may encounter errors or issues that affect the functionality and performance of your vSAN cluster. One of the common scenarios that can cause vSAN cluster errors is when you remove a host and disk groups from a vSAN cluster.

In this article, you will learn how to fix vSAN cluster errors that may occur after removing a host and disk groups from a vSAN cluster. You will also learn how to prevent these errors from happening in the future.

What are the common vSAN cluster errors after removing a host and disk groups?

When you remove a host and disk groups from a vSAN cluster, you need to follow the proper steps and procedures to ensure that the data migration and configuration changes are done correctly. Otherwise, you may encounter some of the following vSAN cluster errors:

• Host with the vSAN service enabled is not in the vCenter cluster: This error means that there is a host that has the vSAN service enabled but is not part of the vSAN cluster in vCenter. This can happen if you remove the host from the cluster without disabling the vSAN service first.
• Host is in a vSAN enabled cluster but does not have vSAN service enabled: This error means that there is a host that is part of the vSAN cluster in vCenter but does not have the vSAN service enabled. This can happen if you disable the vSAN service on the host before removing it from the cluster.
• vSAN network is not configured: This error means that the vSAN network is not properly configured on the host. This can happen if you change the vSAN network settings or remove the vSAN network adapter on the host.
• Host cannot communicate with all other nodes in the vSAN enabled cluster: This error means that there is a network connectivity issue between the host and the other hosts in the vSAN cluster. This can happen if there is a network isolation, misconfiguration, or failure on the host or the switch that hosts the vSAN network.
• Found another host participating in the vSAN service which is not a member of this host’s vCenter cluster: This error means that there is a host that is part of another vSAN cluster but is using the same vSAN network as the current vSAN cluster. This can happen if you have multiple vSAN clusters in the same subnet and you do not use multicast or unicast for vSAN communication.
• vSAN cluster partition: This error means that the vSAN cluster is split into two or more partitions due to network or configuration issues. This can happen if you remove a host or disk group that contains a witness component or a quorum vote for an object, and the remaining hosts or disk groups cannot form a majority.
• Object health error: This error means that some of the vSAN objects are degraded, absent, or inaccessible due to data or metadata loss or corruption. This can happen if you remove a host or disk group that contains a data or metadata component for an object, and the remaining components cannot provide the required fault tolerance level.
• Unicast connectivity check: This error means that the unicast communication between the hosts in the vSAN cluster is not working properly. This can happen if you use unicast for vSAN communication and you do not update the unicast agent configuration after removing a host or disk group from the vSAN cluster.

How to fix vSAN cluster errors after removing a host and disk groups?

The steps to fix vSAN cluster errors after removing a host and disk groups depend on the type and severity of the error. However, here are some general steps that you can follow to troubleshoot and resolve most of the vSAN cluster errors:

Solution 1: Verify the vSAN cluster configuration

Check the vSAN cluster configuration in vCenter and make sure that all the hosts and disk groups are in the correct state and have the correct settings. You can use the vSAN Health Service to perform validation checks for vSAN configuration and detect any configuration problems. You can also use the esxcli commands or the vsantop command-line tool to obtain information about vSAN and to monitor vSAN performance.

Solution 2: Reconfigure the vSAN cluster

If you find any configuration errors or inconsistencies, you need to reconfigure the vSAN cluster to fix them. For example, you may need to add or remove a host from the vSAN cluster, enable or disable the vSAN service on a host, configure or reconfigure the vSAN network on a host, or update the unicast agent configuration on the hosts. You can use the vSphere Client or the esxcli commands to perform these tasks.

Solution 3: Recover the vSAN cluster

If you find any data or object errors, you need to recover the vSAN cluster to restore the data availability and integrity. For example, you may need to resync the vSAN objects, repair the vSAN objects, recreate the vSAN objects, or restore the vSAN objects from backup. You can use the vSphere Client, the Ruby vSphere Console, or the esxcli commands to perform these tasks.

Solution 4: Contact VMware support

If you cannot fix the vSAN cluster errors by yourself, or if you are not sure what to do, you should contact VMware support for assistance. You can upload a vSAN support bundle so VMware service personnel can analyze the diagnostic information and provide you with the best solution.

How to prevent vSAN cluster errors after removing a host and disk groups?

The best way to prevent vSAN cluster errors after removing a host and disk groups is to follow the best practices and procedures for vSAN cluster maintenance and administration. Here are some tips to avoid vSAN cluster errors in the future:

• Plan ahead: Before you remove a host or disk group from a vSAN cluster, you should plan ahead and consider the impact and consequences of your action. You should check the vSAN cluster health and performance, the vSAN object health and placement, the vSAN network configuration and connectivity, and the vSAN fault tolerance and redundancy levels. You should also backup your vSAN data and configuration before making any changes.
• Follow the steps: When you remove a host or disk group from a vSAN cluster, you should follow the steps and procedures recommended by VMware. You should use the vSphere Client or the esxcli commands to perform the tasks. You should also monitor the vSAN cluster status and health during and after the process. You can refer to the vSAN Planning and Deployment documentation for more details.
• Verify the results: After you remove a host or disk group from a vSAN cluster, you should verify the results and make sure that everything is working as expected. You should check the vSAN cluster configuration and health, the vSAN object health and placement, the vSAN network configuration and connectivity, and the vSAN fault tolerance and redundancy levels. You should also test the vSAN functionality and performance and ensure that your virtual machines are running normally.

Frequently Asked Questions (FAQs)

Question: What is vSAN?

Answer: vSAN is a software-defined storage solution that allows you to create a shared datastore from local disks of the hosts in a vSphere cluster.

Question: What are the benefits of vSAN?

Answer: vSAN provides high availability, scalability, and performance for your virtual machines. It also simplifies storage management and reduces storage costs.

Question: What are the requirements for vSAN?

Answer: vSAN requires at least three hosts with local disks in a vSphere cluster, a dedicated vSAN network, and a vSAN license.

Question: How does vSAN work?

Answer: vSAN works by creating vSAN objects from the local disks of the hosts and distributing them across the cluster. vSAN objects are composed of data and metadata components that provide fault tolerance and redundancy. vSAN uses a distributed hash table (DHT) to locate and access the vSAN objects.

Question: How to enable vSAN?

Answer: To enable vSAN, you need to create a vSAN cluster, configure the vSAN network, and claim the local disks for vSAN. You can use the vSphere Client or the esxcli commands to enable vSAN.

Summary

In this article, you learned how to fix vSAN cluster errors that may occur after removing a host and disk groups from a vSAN cluster. You also learned how to prevent these errors from happening in the future. By following the steps and tips in this article, you can ensure that your vSAN cluster is always healthy and functional.

Disclaimer: This article is for informational purposes only and does not constitute professional advice. You should always consult with a qualified IT expert before making any changes to your vSAN cluster configuration or data. The author and the publisher are not responsible for any damages or losses that may result from the use of this article.