What's in a Virtual Machine?

The virtual machine typically is stored on the host computer in a set of files, all of which are in a directory set aside for that particular virtual machine. In these examples, <vmname> is the name of your virtual machine. The key files are:

<vmname>.vmx — the configuration file, which stores settings chosen in the New Virtual Machine Wizard or virtual machine settings editor. If you created the virtual machine under an earlier version of VMware GSX Server on a Linux host, this file may have a .cfg extension.

<vmname>.vmdk — the virtual disk file, which stores the contents of the virtual machine's hard disk drive.

A virtual disk is made up of one or more .vmdk files. If you have specified that the virtual disk should be split into 2GB files, the number of .vmdk files depends on the size of the virtual disk.

By default, all virtual disk space is preallocated when you create the virtual disk. Make sure you have enough disk space on the host before you create a preallocated disk.

If you decide to not allocate all disk space when you create the virtual disk, the .vmdk files grow in size as data is added to the virtual disk. Almost all of a .vmdk file's content is the virtual machine's data, with a small portion allotted to virtual machine overhead.

If the virtual machine is connected directly to a physical disk, rather than to a virtual disk, the .vmdk file stores information about the partitions the virtual machine is allowed to access.

Note: Earlier VMware products used the extension .dsk for virtual disk files.

<vmname>.log or vmware.log — the file that keeps a log of key virtual machine activity. This file can be useful in troubleshooting if you encounter problems. This file is stored in the directory that holds the configuration file (.vmx) of the virtual machine.

<vmname>.vmdk.REDO_xxxxxx — a redo-log file, created automatically when a virtual machine has a snapshot or is in independent-nonpersistent mode. This file stores changes made to a virtual disk while the virtual machine is running. There may be more than one such file. The xxxxxx indicates a unique suffix added automatically by GSX Server to avoid duplicate filenames.

<vmname>.vmss — the suspended state file, which stores the state of a suspended virtual machine.

Note: Some earlier VMware products used the extension .std for suspended state files.

<vmname>.vmsn — the snapshot state file, which stores the running state of a virtual machine at the time you take a snapshot of it.

<vmname>.vmx.sav — the configuration snapshot file, which stores the configuration of a virtual machine at the time you take a snapshot of it. If you created the virtual machine under an earlier version of GSX Server on a Linux host, this file may have a .cfg extension.

There may be other files as well, some of which are present only while a virtual machine is running.

When you create a virtual machine, by default the virtual machine is private, which means you are the only user who can access it. If you choose the custom path when creating the virtual machine, you can specify that all users can access the virtual machine.

When a virtual machine is private, it appears in the inventory of the console of the user who created it. The virtual machine does not appear in the inventory of consoles for other users connected to the host. The virtual machine appears in the VMware Management Interface only when you are logged in as the user who created the virtual machine.

When the virtual machine is running, the actions you can take with it depend upon your permissions. For more information about permissions, see Understanding Permissions and Virtual Machines.