As part of the VCAP6 – DCV  we are going to perform Objective 1.1 Edit System Swap / Scratch Configuration

For the complete VCAP – DCV Checklist visit Checklist

Edit System Swap / Scratch Configuration in VSphere 6

Swap file
VMKernal swap file is serves as a backing store for the virtual machine’s RAM contents. By default it’s created in the same location as the virtual machine configuration file. It’s created by the ESXi host when the virtual machine is powered on. So if this file cannot be created then the Virtual machine cannot power on. So if we consider a clustered environment the Swap settings can be configured on a VMware cluster level.

Open the Web Client – Right click on your Cluster object and select the Settings. Under the Configuration click on General. There you will see an option to edit Swap File Location.

We basically have two option either to store the swap files in the same directory as the virtual machine or store the swap files in the datastore specified by the host.

We will choose the second option here to select a datastore to manage the swap file creation.

But keep in mind as the VMware warns that using datastore that is not visible to all the hosts in the cluster will affect the vMotion performance.

Open the VMware Client and Select the host you want to change its swap file location and click on Configurations then under the Software tab click on the “Virtual Machine Swapfile Location” Then Edit and choose the Datastore you wish to use for managing swap files.

Scratch partition
It’s basically a 4 GB sized VFAT partition to hold such as troubleshooting information such as logs and core files for VMware Support. Even if this partition is not available ESXi will still function and keep the information in RAMDisk. However RAMDisk information will not stay beyond a restart. If there are storage resource constrains we can move the scratch partition to a shared storage.

SSH in to any host and find out below Unique datastore identified information.

We will need the ID corresponding to the Datastore02-SDD where we have already created a Root folder named Scratch and created a folder structure for all the 3 VMHosts.


Right click the HOST and click on Settings>Advanced System Settings and search for scratch it will show two entries as below from that edit the entry ScratchConfig.ConfiguredScratchLocation

Once the configuration has been applied take a restart of the particular VMhost. After the restart if you browse the corresponding location in the datastore you will see below folder structure.


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