Since I am using Windows, WinSCP is the next tool I tried.

First, start the host’s SSH service by

1. Select the host in vCenter and click Configure tab.
2. Then select Services from the left-side panel under the System section.
3. Start the SSH service there.

Now it’s ready to use WinSCP. Simply log in with the host’s root account and then navigate to the storage volume at /vmfs/volumes.

Most of the time, a restart would get you going again. But today, a simple restart won’t cut it. I had to try a few different ways to finally get the login page again.

First of all, if SSH isn’t an option, you will need to get access to the console, which mostly you can through the ESXi server management portal.

Press Alt+F1 to get to the login screen and use root user to log in. I hope you still remember your root password. If not, check this one out. Once logged in, launch shell, by

shell.set --enabled true
shell

Then, run the following to check the services status.

service-control --status --all

If you see any stopped services, run the following to start all services.

service-control --start --all

Then wait for another 15 minutes before checking the web portal again.

While you are in the console, you should also check and make sure none of the logical drives should be full.

df -h

A few other resources to look at if the above doesn’t help.

• Reindex the database – https://www.running-system.com/vmware-vcsa-error-503-service-unavailable/
• VMware KB – https://kb.vmware.com/s/article/67818
• Due to the vSphere web client – https://chrisdsibug26.wordpress.com/503-service-unavailable-error-when-connecting-to-the-vcenter-server-using-the-vsphere-web-client/
• Due to the corrupted certificate store – https://kb.vmware.com/s/article/80020

/Updated on Oct. 23, 2022/

To fix the issue due to the corrupted certificate store,

Download the crl-fix.sh script attached to the VMware KB, and transfer the file to the vCenter Server via the tool WinSCP. You may need to follow this first.

Then run the script.

First, grant the script execution permission.

chmod +x crl-fix.sh

Then, run the script.

./crl-fix.sh

However, if you got the error message saying no such file or directory, run this first and try again.

sed -i -e 's/\r$//' crl-fix.sh

It could take a quite long time to see any results from the script. When it is finished, it should stop and restart the vmafdd service again.

Then, restart all the services of the VCSA.

Here is what I managed to do.

First of all, reset the “root” password.

Log in to the ESXi host that powers the vCenter Appliance and do the following steps:

1. Open the vCenter Console and reboot it.
2. Press the “e” key right after the VCSA Photon OS start to enter the GNU GRUB Edit menu.
3. Add the following line at the end of the line that starts with the word “linux”.
   rw init=/bin/bash
4. Press F10 to continue booting once done.
5. Then run the following commands

mount -o remount,rw /
passwd
unmount /
reboot -f

Now go to https://serverip:5480/ to access the vCenter Server Appliance using the new password.

Now, let’s reset the Single Sign-On Password:

Log in vCenter Server Appliance to enable SSH and then log in as the root user via SSH.

Run the following command to enable access to the bash shell.

set --enable true

Type “shell” and press enter. And then run:

/usr/lib/vmware-vmdir/bin/vdcadmintool

Press 3 to enter the Reset Account Password option to generate a new temporary password that you can log in to vCenter Server. From there, you can change the password to whatever you want.

First of all, enable SSH service so you can tune in through SSH to perform the commands.

To get the list of storage devices installed on the host, run

esxcli storage core device list

Find the one that has Is SSD: true and mark down the device ID for the next step.

esxcli storage core device smart get -d=deviceID

The output will look something like this. Mine says all N/A so there could be something still missing.

You can archive the same results for all disks in once by running a script called smartinfo.sh in the following folder:

/usr/lib/vmware/vm-support/bin

If you are satisfied with the information provided by this builtin command, great. Otherwise, you may want to try a modified copy of smartmontools for VMware, thanks to this vExpert.

Here is a step of how to get the tool installed on VMware host.

1. Download smartctl-6.6-4321.x86_64.vib.
2. Upload it to the /tmp folder of the ESXi host.
3. SSH to the host.
4. Set the ViB acceptance level to CommunitySupported.
5. Then install the package.

esxcli software acceptance set --level=CommunitySupported
esxcli software vib install -v /tmp/smartctl-6.6-4321.x86_64.vib

The tool is installed at /opt/smartmontools folder and works just like the Linux version.

/opt/smartmontools/smartctl -d sat --all /dev/disks/[DISK]

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Windows Explorer

Supporting VMDK seems to be a feature built right into the Windows system. If you are using a system that runs Windows 7 or above, you may be able to map the image file right through Windows Explorer.

Navigate to the fold that hosts VMDK file in Windows Explorer, right-click the file and choose Map Virtual Disk.

Select the drive letter you want to map to, and click OK button on the Map Virtual Disk window.

To disconnect, right-click the mapped drive and choose Disconnect Virtual Disk.

It works beautifully when it works. When it’s not, it’s time to seek alternative options.

VMware Workstation

VMware Workstation is VMware’s desktop solution for virtualization. It has the “Map Virtual Disks” feature built in that opens VMDK in a wider format. If the method of using Windows Explorer doesn’t work out, VMware Workstation is next one in the line to try.

Go to File menu and select Map Virtual Disks… from the drop-down list to start the process.

vSphere Disk Development Kit

The  “VMware-mount” command line is the one you can use to mount a VMDK disk without a GUI interface. The tool is part of the vSphere Disk Development Kit, so you need to download and install the kit to use the tool.

To mount a VMDK file (saved at C:\temp) in read-only mode use the following command:

vmware-mount.exe X: “C:\Temp\TestVM.vmdk”

If the VMDK file contains more than one partition you can use the parameter /v:x to mount the other volumes:

vmware-mount.exe /v:2 X: “C:\Temp\TestVM.vmdk”

If you need a writeable access, just use the parameter “/m:w“. This is extremely helpful if you need to replace a broken system file.

vmware-mount.exe /m:w X: “C:\Temp\TestVM.vmdk”

If you want to list all the mounted virtual drives use /L:

vmware-mount.exe /L

The command line is easy to use and powerful, but I am finding it’s not so easy to get the Development Kit installed on my computer for some reason.

OSFMount

OSFMount is a 3rd party free image mounting tool that mounts not only ISO format images but also VMDK files in Windows with a drive letter. It works on pretty much all versions of Windows.

It’s fairly easy to use the tool. Click the Mount new… button at the bottom of the window and follow the instructions.

If you have other alternative options, feel free to share. It’s never enough to have a reliable tool that does the job well in hand.

/Update on July 8, 2020/

As some of the commenters pointed out, the open-source archiving tool 7-Zip does happen to be the easiest way to open the VMDK file for you. By all means, give 7-Zip a try first and if it failed, try something mentioned above.

Concerning about the performance impact that might be? Check out the VM Encryption Performance Whitepaper by VMware to find out.

In short, according to the Executive Summary in the whitepaper, We show that while VM encryption can lead to bottlenecks in I/O throughput and latency for ultra-high-performance devices (like a high-end NVMedrive) that can support hundreds of thousands of IOPS, for most regular types of storage, like enterprise class SSD or VMware vSAN, the impact on I/O performance is very minimal.