ESXi 5.5 Host Disconnects From vCenter Server: Causes and Fixes

Hello Dev, welcome to our journal article about ESXi 5.5 host disconnects from vCenter server. If you’re an IT professional who manages virtualized servers, you’ve probably encountered this issue at some point. It can be frustrating when a host suddenly disconnects from vCenter and you’re unable to manage it. In this article, we’ll explore the various causes of this problem and provide solutions to help you resolve it.

What is ESXi 5.5 Host Disconnects From vCenter Server?

ESXi 5.5 host disconnects from vCenter server occurs when an ESXi host loses the connection to its vCenter server. This means that the host is no longer being managed by vCenter and cannot be monitored or controlled. The host may still be running virtual machines, but you won’t be able to manage them through vCenter.

Causes of ESXi 5.5 Host Disconnects From vCenter Server

There are several reasons why an ESXi host might disconnect from its vCenter server. Let’s take a look at some of the common causes:

1. Network Connectivity Issues

The most common cause of ESXi host disconnection is network connectivity issues. If the network connection between the host and vCenter server is interrupted or lost, the host will disconnect from vCenter. This can happen due to various reasons such as firewall settings, network misconfiguration, DNS issues, etc.

To resolve this issue, check the network settings of the host and vCenter server. Make sure that the DNS name resolution is working correctly and that the firewall is configured to allow traffic between the host and vCenter server.

2. ESXi Host Configuration Issues

Another reason for ESXi host disconnection is configuration issues on the host itself. This can happen if the host is misconfigured or if there are compatibility issues. For example, if the host is running an unsupported version of ESXi or if it has incompatible hardware, it may disconnect from vCenter.

To resolve this issue, check the compatibility of the hardware and software on the host. Make sure that the host is running a supported version of ESXi and that its hardware is compatible with vCenter.

3. vCenter Server Issues

In some cases, the issue may be with the vCenter server itself. If the server is experiencing problems or if it is misconfigured, it may not be able to manage the ESXi host, causing it to disconnect.

To resolve this issue, check the vCenter server logs for any errors or issues. You can also try restarting the vCenter server or reinstalling it to fix any configuration issues.

How to Fix ESXi 5.5 Host Disconnects From vCenter Server

Now that we’ve looked at the causes of ESXi host disconnection, let’s explore some solutions to fix the issue:

1. Check Network Connectivity

The first step in resolving ESXi host disconnection is to check the network connectivity between the host and vCenter server. Make sure that the DNS name resolution is working correctly and that there are no firewall issues blocking the communication.

Network Connectivity Checklist	Status
Check DNS name resolution	OK
Check firewall settings	OK

2. Check ESXi Host Configuration

The next step is to check the configuration of the ESXi host. Make sure that the host is running a supported version of ESXi and that its hardware is compatible with vCenter. You can also check the host logs for any errors or issues.

ESXi Host Configuration Checklist	Status
Check ESXi version compatibility	OK
Check hardware compatibility	OK
Check host logs for errors	OK

3. Restart vCenter Server

If the issue persists, you can try restarting the vCenter server. This may help resolve any configuration or connectivity issues that may be causing the host disconnection.

4. Reinstall vCenter Server

If all else fails, you can try reinstalling the vCenter server. This will reset the configuration and may help resolve any issues that may be causing the host disconnection.

FAQs About ESXi 5.5 Host Disconnects From vCenter Server

Q1. How do I know if my ESXi host is disconnected from vCenter?

A1. If your ESXi host is disconnected from vCenter, you will see a warning or error message in the vCenter console. You can also check the ESXi host logs for any disconnection events.

Q2. Can I still manage virtual machines on a disconnected ESXi host?

A2. Yes, you can still manage virtual machines on a disconnected ESXi host. However, you will need to manage them directly on the host using the vSphere Client.

Q3. Can firewall settings cause ESXi host disconnection?

A3. Yes, firewall settings can cause ESXi host disconnection if they are blocking the communication between the host and vCenter server. Make sure that the appropriate firewall ports are open for vCenter communication.

Q4. What should I do if my ESXi host keeps disconnecting from vCenter?

A4. If your ESXi host keeps disconnecting from vCenter, you should first check the network connectivity and host configuration. If the issue persists, you can try restarting or reinstalling vCenter server.

Q5. Can incompatible hardware cause ESXi host disconnection?

A5. Yes, incompatible hardware can cause ESXi host disconnection if it is not supported by vCenter. Make sure that the hardware on the host is compatible with vCenter before adding it to the server.

Conclusion

ESXi 5.5 host disconnects from vCenter server is a common issue that can be caused by various factors. In this article, we’ve explored the common causes of the issue and provided solutions to help you resolve it. By following the steps outlined in this article, you can quickly get your ESXi host back online and manage it using vCenter.