Backup and Restore of ESXi host configurations with PowerCLI

I’m a big fan of PowerCLI one-liners. 🙂

Before performing updates, upgrades or any other maintenance on ESXi hosts, you should backup your ESXi host configuration. Setting up a new ESXi host as replacement is a no-brainer, but rebuilding a lost configuration can be a PITA and might take hours.

In the old times it was necesary to open a SSH shell connection or to use vSphereCLI to issue backup commands to ESXi hosts. Recently I realized that there is a very handy PowerShell commandlet to backup and restore the configuration. Continue reading “Backup and Restore of ESXi host configurations with PowerCLI”

vMotion fails at 21% with error 195887371

How to troubleshoot vMotion issues

Troubleshooting vMotion issues is in most cases a matter of networking issues. I will demonstrate in this case how to trace down the problem and how to find possible culprits.

What’s the problem?

Initiating a host vMotion between esx1 and esx2 passes all pre-checks, but then fails at 21% progress.

Migrate virtual machine:Failed waiting for data. Error 195887371. The ESX hosts failed to connect over the VMotion network.

See the error stack for details on the cause of this problem.
Time: 07.01.2018 19:08:08
Target: WSUS
vCenter Server: vc
Error Stack
Migration [167797862:1515348488969364] failed to connect to remote host <192.168.45.246> from host <10.0.100.102>: Timeout.
vMotion migration [167797862:1515348488969364] vMotion migration [167797862:1515348488969364] stream thread failed to connect to the remote host <192.168.45.246>: The ESX hosts failed to connect over the VMotion network
The vMotion migrations failed because the ESX hosts were not able to connect over the vMotion network. Check the vMotion network settings and physical network configuration. 
Migration [167797862:1515348488969364] failed to connect to remote host <10.0.100.102> from host <192.168.45.246>: Timeout.
vMotion migration [167797862:1515348488969364] failed to create a connection with remote host <10.0.100.102>: The ESX hosts failed to connect over the VMotion network
Failed waiting for data. Error 195887371. The ESX hosts failed to connect over the VMotion network.

Continue reading “vMotion fails at 21% with error 195887371”

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.

PSOD

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

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.

 

vSphere Web Client vs. vSphere Client

Ein Argument, das viele Kunden vom Upgrade auf vSphere 6.5 abhält, ist der Verlust des vSphere-Clients (C# Client). Der auf Adobe Flash basierende Web-Client wurde nie richtig angenommen. Auch wenn einige Funktionen nur im Web-Client verfügbar sind, erledigen vSphere-Admins 95% ihrer Tätigkeiten im klassischen C#-Client. (Ich muss gestehen, ich gehöre auch dazu).

Dabei wird oft das beste Argument zum Upgrade übersehen: Der HTML5 vSphere-Client. Ursprünglich als Fling gestartet, ist er nun auch fest in vSphere 6.5 integriert. Er benötigt kein Flash mehr und überzeugt auch optisch durch die klaren Linien der Project-Clarity UI.

Continue reading “vSphere Web Client vs. vSphere Client”