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Reuse VSAN Claimed Disks as VMFS Datastore

During a test I used an old disk that has been previously used by Virtual SAN. The disk did not appear during the datastore creation process. I miss a flash drive here:

datastore-creationThe problem is that the disk has not been cleared from it's VSAN configuration. It has still valid VSAN partitions, so the ESXi "claims it for VSAN" what makes it impossible to create a VMFS filesystem.

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vSphere 5.5 U2 C# Client can now edit Hardware Version 10 VMs

Slightly hidden in vSphere 5.5 Update 2 there is a new vSphere C# Client that can edit Virtual Machines running the latest Virtual Hardware (vmx-10). Instead of getting an error message when trying to edit Virtual Machines with Hardware Version 10 you can now reconfigure these machines with the legacy C# client. Understandably you can only edit pre-5.1 features. All 5.1/5.5 features are still only available with the vSphere Web Client.

With the vSphere Client you would usually see the following error message:


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ESXi 5.5 affected by OpenSSL CVE-2014-0160 aka Heartbleed

[Last Update April 19, 2014 - Patches available]

There are a lot of news according to the recently published OpenSSL vulnerability. The bug, also known as "Heartbleed", allows attackers to steal informations that are protected by the SSL/TLS encryption.

Is VMware ESXi and the vCenter affected?
There is currently no official statement from VMware regarding this issue. After some research I found affected versions im VMware products. Here are my findings:

The affected versions are OpenSSL 1.0.1 through 1.0.1f.

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Permanently disable ESXi 5.5 coredump file

The new coredump file feature in vSphere ESXi 5.5 creates a file to extend the coredump partition. This usually happens when you upgrade from a previous version to ESXi 5.5, or you install ESXi to a USB drive or SD card. This coredump file is created on a random VMFS datastoore by using a smart selection algorithm. This random placement causes different kind of problems, for example when you want to delete a datastore. Another problem might occur in an EMC VPLEX deployment where you want to failover VMs to the secondary site in a PDL situation (VMkernel.Boot.terminateVMOnPDL=1 / Disk.AutoremoveOnPDL=0). Datastores that had a coredump file configured can't get mounted back when the volume leaves the PDL state after a site failure has been fixed.

To workaround this issue you might want to permanently disable the coredump file. You can't just disable it, as it gets created automatically after a reboot.

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