Here is the code for creating a distributed virtual switch. Input is sdkConnection. The code assumes you have only the root network folder.
//sdkConnection is an input parameter of type VC:SdkConnection
var allNetFolder = sdkConnection.getAllNetworkFolders();
//Assuming you have no network folder but the root folder
var netFolder = allNetFolder[0];
var dvsCreateSpec = new VcDVSCreateSpec();
var uplinkNames = new Array();
uplinkNames.push("uplink1");
uplinkNames.push("uplink2");
dvsCreateSpec.productInfo = new VcDistributedVirtualSwitchProductSpec();
//The Version of the DVS
dvsCreateSpec.productInfo.version = "4.1.0";
dvsCreateSpec.configSpec = new VcVMwareDVSConfigSpec();
//The name of the DVS
dvsCreateSpec.configSpec.name = "DVSwitch_Backup";
dvsCreateSpec.configSpec.uplinkPortPolicy = new VcDVSNameArrayUplinkPortPolicy;
dvsCreateSpec.configSpec.uplinkPortPolicy.uplinkPortName = uplinkNames;
//Optional
dvsCreateSpec.configSpec.maxMtu = 9000;
dvsCreateSpec.configSpec.maxPorts = 20000;
task = netFolder.createDVS_Task(dvsCreateSpec);
