Category: vSphere

6. August 2025

vSphere 8 Update fails: Error in method invocation Timout happens while sending message to microservice

This error occurs due to an outdated PID file of the update microservice or an error during staging of corrupted media. Strangely enough, I requested the update via the VAMI interface (port 5480), so it may have been corrupted during download. As always, there is a solution, and this time there are even three. The first solution is to restart vCenter, but this did not […]

21. July 2025

Failed to move a VM out of maintenance mode candidate host since the VM is in manual mode!

The vSphere 7 to 8 upgrade (and soon to vSphere 9) series continues successfully, this time I had the above-mentioned challenge during the Check Compliance or Run Pre-Check State inside Image Based Patching. The error message says that there are VMs that cannot be migrated Fully Automated, which is very useful in the context of Image Based Patching. You want to use the luxury of […]

18. June 2025

Cannot download VIB: “This might be because of network issues or the specified VIB does NOT exist or does NOT have a proper ‘read’ privilege set. Please make sure the specified VIB exists and is accessible from vCenter”

Keeping an eye on the clock and sensitizing my customer (vSphere 7 EOL, Oct 25), I was on a vSphere 7 environment today where we wanted to install the latest patches. However, I was confronted with the error message above. Let’s fix this real quick, first we need SSH access to our VCSA, via the Shell Command and Stop the VMware Update Manager Service: Now […]

3. December 2024

Host prevents entering Maintenace Mode: There are insufficient memory resource on standby hosts

In a vSphere 8 – 2-Node Cluster Update I have had to deal with the following message during the Check Compliance process: High Availability (HA) Admission Control is enabled and set to specify a failover host, which is reserved for HA failover purposes. However, in a 2-node cluster you ultimately only have the 2nd host and if the resources on this host are not sufficient, […]

30. November 2024

A problem with one or more vFAT bootbank partitions was detected. (PSOD Alarm!)

During a VMware vSphere 7 to 8 upgrade, more precisely after the compliance check, I was confronted with the above error message. In this blog post I would like to show you how to solve the problem. Corrupt vFAT partitions already existed in vSphere 6.7 times and unfortunately they also appear today with vSphere 8. The problem? If you go through with the upgrade in […]

4. November 2024

Image Compliance shows hardware compatibility issues

During an ESX server cluster update on image basis, I was confronted with a strange thing. The message says that there are hardware compatibility issues. However, if you look at the details, you will quickly realise that there is nothing under the firmware version. If you then scroll down a little, you will see the warning ‘Device is incompatible with the Driver/Firmware in clusters image‘. […]

28. October 2024

vSphere UI Client Plugin is at N/A state before vSphere 8 Upgrade

We are rapidly approaching the end of vSphere 7 support (October ’25), and during a vSphere 8 upgrade pre-check at my customer’s site, we ran into the problem mentioned in the title. The so-called “…vmware.h4…” plugin was in a N/A state. In the past this plugin has appeared several times and should be unregister beforehand, this is the VMware Cloud Director Availability Plugin, which cannot […]

22. March 2024

The number of VMware vSphere HA datastores for this host is 0, which is less than required: 2

Recently I had the situation that at cluster level, the vSphere HA displayed a heartbeat of datastores at zero, whereby I have defined two specific datastores under vSphere HA settings under Heartbeat Datastores and these must always be pingable. The two defined datastores were no longer visible under Datastores, which is why the warning appeared. After consulting with the storage team, it turned out that […]

1. March 2024

How to Reset vCenter 8.0 Root Password

Yep, there are still vCenter’s out there with expired root passwords. 😀 Therefore, I will describe the workaround to reset the root password for vCenter 8.0, which also works for vSphere 6.5 through today’s releases. First, take a snapshot of your vCenter VM: Then switch to the ESXi Host Client and open a virtual console from the vCenter VM: Now reboot the vCenter and watch […]

24. January 2024

Bug Alert: Powering On VM in VMware vCenter stucks at 66%

Today I had a strange issue in my vCenter, after a maintenance operation on my server I wanted to power on several VMs and I noticed that they got stuck at 66% in the power on process. There are no warnings or errors. Some VMs take up to 60 minutes to power on and some remain at 66%. Officially, I could not find a KB […]