Virtualization page 1 of 6 for 56 posts

Backup using vim-cmd To ensure that the configuration of the target ESXi host is synchronized with persistent storage, run the following command: vim-cmd hostsvc/firmware/sync_config To back up ESXi configuration, run this command: vim-cmd hostsvc/firmware/backup_config The command will produce a link for downloading the configBundle.tgz archive. Note that you have to replace the asterisk in the provided link with your IP/FQDN. Alternatively, access the backup file in the /scratch/downloads Continue Reading...

Configuration mismatch: The virtual machine cannot be restored because the snapshot was taken with VHV enabled.

Upon migrating a VM from one ESXi host to another ESXi host, I received the following message. Configuration mismatch: The virtual machine cannot be restored because the snapshot was taken with VHV enabled. To restore, set vhv.enable to true Check and confirm on both hosts that /etc/vmware/config has vhv.enabled = "TRUE" in the configuration. This modification on the mismatched host requires a reboot. Continue Reading...

Proxmox Nested VM – Enable MAC spoofing Hyper-V

Windows 11 > Windows Hyper-V > Proxmox VE 7.2 > Debian 11.2 VM In order for my Debian VM to be able to access the DHCP/network resources provided by devices on the outside of my Hyper-V server, I needed to enable Forged Transmits (MAC spoof) on my Proxmox VE 7.2 Hyper-V VM. Now I can continue with my Debian VM installation with DHCP (netinstall). Continue Reading...

Enable nested virtualization for VM in Hyper-V

Nested virtualization is available on Windows 10 build 19636 and later. As far as I understand, AMD support will be officially available as part of Windows 11 and Windows Server 2022. Both products are expected in the second half of 2021. Enable Nested Virtualization Get the virtual machine intending to enable nested virtualization on using Powershell. get-vm Now with the name of the VM, enable nested virtualization. Set-VMProcessor -VMName 'Windows 11' -ExposeVirtualizationExtensions Continue Reading...

Case of Dead Path on ESXi

I had 8 paths go down to a dead state on an ESXi host.  The paths were MRU via Fiber Channel to a storage array.  One path worked and it was configured as RR path.
I knew this wasn't a physical issue, it had to be a software/configuration issue on my host because there were:

No storage array errors
Additional hosts in the cluster had no problems
One path still worked from the HBA

Looking at the log (/var/log/vmkernel.log) I searched for one of the LUN identifiers, in my case ":L30" which Continue Reading...

A general system error occurred: esxi1: CHAP setting not compatible.

During datastore creation in vSphere using the Nimble vCenter plugin, I get the following error:
A general system error occurred: esxi1: CHAP setting not compatible. hba=vmhba33
In vSphere Client I went to my ESXi host then Configuration, Storage Adapters, iSCSI Software Adapter.  Taking a look at vmhba33 Properties then CHAP... I see that there was a CHAP setting in there for an old Drobo system I had connected at one point.

Changing the option to Do not use CHAP resolved my issue.  I'm not Continue Reading...

Intel Xeon E7540 replaced with X7560

Recently I've been dealing with CPU RDY of about 5% across two ESXi hosts. I've load balanced the best I could given necessary workloads and was able to get CPU RDY down to about 3-4% which still isn't great. I made the decision to grab a few Intel Xeon X7560 processors to replace the existing Intel Xeon E7540 processors to help alleviate some pressure. The main reason was moving from 6 core E7540 to 8 core X7560. The specs are pretty close, including same Nehalem family for my EVC needs. Continue Reading...

Performance tuning iSCSI Round Robin policies in ESXi for Nimble storage

Here's an ESXi console script to loop through each Nimble eui.* adapter and set IOPS=0 and BYTES=0 (per Nimble recommendations).
for x in `esxcli storage nmp device list | awk '/Nimble iSCSI Disk/{print $7}' | sed -e 's/(//' -e 's/)//'`; do
echo $x
esxcli storage nmp psp roundrobin deviceconfig set -d $x -t bytes -B 0;
esxcli storage nmp psp roundrobin deviceconfig set -d $x -t iops -I 0 ;
esxcli storage nmp psp roundrobin deviceconfig get -d $x;
Note: If you change the order above and set Continue Reading...

IBM System X3850 Disable Processor Power Management

In order to work around the issue processor power management has to be disabled in system UEFI and vSphere Client.
To change power policies using server UEFI settings:

Turn on the server.
Note: If necessary, connect a keyboard, monitor, and mouse to the console breakout cable and connect the console breakout cable to the compute node.
When the prompt 'Press <F1> Setup' is displayed, press F1 and enter UEFI setup. Follow the instructions on the screen.
Select System Settings --> Operating Continue Reading...

My Notes and Benchmarks on VMware Flash Read Cache

I've spent some time exploring and studying the use and configuration of VMware Flash Read Cache (vFRC) and its benefits.  These are my notes.
Useful Resources

VMware Flash Read Cache 1.0 FAQ
vSphere 5.5 Flash Read Cache Documentation

On a guest virtual machine, vFRC is configured in Disk configuration area.  The virtual machine needs to be on version 10 hardware.  vSphere needs to be minimum version 5.5.

I took a baseline benchmark of a simple Windows Server 2016 virtual machine Continue Reading...