History of Virtualization Technology

It's a simple overview made by me, about the virtualization technology, goals and basic knowledge of hypervisor and virtual machine concepts for the beginners.

Irrational ESXi host disconnecting problem

Respect to the List of VMware Hardware Compatibility Guide (VMware HCL) I want to tell about one of my strange experience related to this pre-requirement checking operation.

Some months ago we had a big issue in virtual infrastructure at one of our projects that caused many irregular problems. Basically situation seems to be normal, but web client console suddenly shows all hosts (inside and outside of the cluster) are disconnected from the vCenter server, while they had been really working correctly. When I checked them, all of the following situations were OK:

• Health status of all hosts & VMs are normal.
• VPXA and Hostd work without problem and ESXi host is reachable on the network.
• All distributed switches (VDS) and dvPortGroup seem to be healthy and all virtual machines are connected.
• VCSA management interface (VAMI) shows the vCenter components are healthy.

After two days of checking and investigation of all logs related to the hosts and vCenter server, sadly we couldn't find the cause of this problem. So we decided to restart them one by one. But suddenly after restarting the vCenter server, we encountered with another unknown problem: vCenter's machine is gone. 

Because the hosts have been added in Lockdown Mode (Normal type) I forced to try registering that VM with CLI in shell access via using the following vim-cmd. 

vim-cmd  solo/registervm  /vmfs/volumes/SAN1/VCSA/VCSA.vmx

But after re-add and power-on the VCSA, nothing fixed. Sadly dvportgroup were not in Ephemeral Port Binding type and we couldn't connect the vCenter vNIC to the VDS.

In the next step of troubleshooting, I thought it's necessary to turn back to the first point and check everything with more details about the hosts from the beginning. After reviewing them in VMware HCL, I saw the physical hosts were not compatible with the ESXi version. (Servers are HP Proliant DL380 G8 and ESXi version is 6.7U3). So the only available solution left for me is downgrade the host to an ealier version. At last happily ever after doing this,  normal situation returned back and everything worked correctly.

But the only problem that has been left is related to the VDS version. After finding the downgrade is the only solution left for us, Unfortunately saw that ESXi host couldn't attach to the VDS version 6.6, because this version is incompatible with ESXi 6.5 u3. So we forced to deploy the VDS structure again.

As a general conclusion,  for avoiding abruptions or problems like this one that I mentioned before, always remember to check the VMware hardware compatiblity list before you choose the ESXi version as the suitable hypervsior for your physical server. It's not a recommended option, because it's necessary to observe. So do not ignore the vmware HCL information.

vSphere 7 has been released

VMware release the vSphere 7 on this week. There are many changes (Cloud improvements) and new features (BitFusion, VM HW Ver17) in this release especially in storage (VSAN7)  and interoperability (vCenter Server Update Planner)

For more information, you can read the following links:

• https://blogs.vmware.com/vsphere/2020/03/vsphere-7-features.html
• https://virtuallyinclined.com/2020/03/10/vsphere-7-whats-new
• https://www.ivobeerens.nl/2020/03/10/whats-new-in-vmware-vsphere-7/

Introduce the VAMI Interface

Troubleshooting Microsoft Active Directory via the NTDSUtil CLI

That's cool to fix some of related problems with the Microsoft AD as one of the main and important services in windows server. NTDSutil is one of the greatest tools for AD troubleshooting. In this video I review and introduce some syntax of this useful CLI. I hope you enjoy it ;)

Executing virtual machine related-operations via the ESXi Shell

 Consider a situation that you don't have access to any type of vSphere client (and also web client). What should we do for managing virtual infrastructure objects and components? especially management operations for virtual machines is a some kind of regular procedure that you may need to run immediately. So there is many CLI for such as this situation that I want to review in this post.

 To check all of running VMs in host-level:

esxcli vm process list

 Also you can stop them via running kill syntax with the related world-ID:

esxcli vm process -w 12345 -t soft

(You can try each one of soft, hard & force with -t based on VM status)

But there is nothing to made power-on a VM with esxcli, so we can go for the next CLI: vim-cmd

 vim-cmd vmsvc/power.on /vmfs/volumes/{datastore-name}/{vm-directory}/vm.vmx

You can execute many other virtual machine operations like power.off, shutdown, reset, reboot and so on.

 If you want to check all running VMs via the vim-cmd you can run the following command too:

vim-cmd vmsvc/getallvms

 If you want to check the status of a VM with more details you can use the get.summary. Look at the results of following command:

vim-cmd vmsvc/get.summary 5 (vmid) | grep State

 And also with get.runtime to recieve many detail information about that VM like the boot time:

vim-cmd vmsvc/get.runtime 5 | grep boot

 

And for gathering more information about the guest OS like the VMkernel port IP Address, Subnet mask, MAC address and ESXi configured FQDN:

 

For register/unregister a VM you can run the following operations:

vim-cmd solo/register ....

vim-cmd vmsvc/unregister ...

 Attention: There is many dangerous operations like destroy or device.diskremove so be careful of using each of them.

In another post I will review about the vim-cmd hostsvc command-line

I hope it has been useful for you all guys ;)

 

   

VMware Horizon View required network ports

Special thanks for the VMware, because of publishing a series of wonderful posters about the network communications and related TCP/UDP ports for every required connections from each VMware VDI components, Horizon View. They are very helpful for troubleshooting network problems related to this area:

Network Ports in VMware Horizon 7