VMware releases patches for Meltdown and Spectre bug

Important patches available

VMware has issued Security Advisories for the recent Meltdown and Spectre bugs to address side-channel analysis due to speculative execution.

I recommend reading a post by Anton Gostev (Veeam), which i reposted yesterday.

It includes patches for VC, ESXi, Workstation and Fusion.


VMware vSphere, Workstation and Fusion updates add Hypervisor-Assisted Guest Remediation for speculative execution issue.

There’s also an update to VMSA-2018-0002


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Resilient Network Infrastructure for Virtualization

Network topology 101 for Virtual Infrastructures

I usually don’t like writing about obvious matters. Yes, fire is hot – night is dark and ice is cold. But in recent times I’ve witnessed some network topology designs (?), that made me frown.

I admit, that in some cases the situation is based on a lack of budget or just structures that have grown over years. I can understand that and it’s no shame. It’s my job to give advices and help to re-design.

No matter how many resources you have – if you use them without thinking, it will never be enough.

On the other hand there are environments who boast with high class components that have cost a fortune and which are organized in such an inefficient way that it almost hurts.

This article is not intended as a networking deep-dive. It’s a shallow 101 about network design that should be common knowledge. It’s a guide for the novice but I’d be happy to get responses by experts too.

The Basics

First let’s start with four simple networking requirements for Virtual Infrastructures.

  • redundancy
  • resiliency
  • bandwidth
  • latency

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create kernel panic on ESXi

There are situations when you need to check cluster reactions after a ESX host crash. For example to see if HA will start VM on other hosts.

The easiest method is to pull a hosts powercord. But there ar more elegant ways to let a host crash.

Warning! Do not use on productive systems! This is for testing purposes under controlled conditions only. Use at your own risk.


You can trigger a Purple-Screen-of-Death (PSOD) by issuing a special command that causes a kernel panic.  Use the VMkernel Sys Info Shell (vsish).

First you need a SSH connection to your host. Change to vsish

set /reliability/crashMe/Panic

Alternatively you can issue the command together with parameters.

vsish -e set /reliability/crashMe/Panic 1

Your host will end up in a PSOD and can be restarted afterwards.