PowerCLI - Connecting to multiple vCenters

By default the connection mode of PowerCLI is set to "Single" which means if you connect to multiple vCenter or server instances, only the last established one is used.

To run a command such as "Get-VM" against all connections, set the connection mode to multiple with the following command:

Set-PowerCLIConfiguration -DefaultVIServerMode Multiple -Confirm:$false

Output:

Proxy Policy    Default Server  Invalid Certificate 
Mode            Action              
------------    --------------- --------------------
UseSystemProxy  Multiple        Unset

To get the current config use Get-PowerCLIConfiguration:

Get-PowerCLIConfiguration

Output:

Proxy Policy    Default Server  Invalid Certificate 
Mode            Action              
------------    --------------- --------------------
UseSystemProxy  Multiple        Unset

Reference: http://www.vmware.com/support/developer/PowerCLI/PowerCLI50/html/Set-PowerCLIConfiguration.html