OMS resourceId example

        {
            "apiVersion": "2015-05-01-preview",
            "type": "Microsoft.Compute/virtualMachines/extensions",
            "name": "[concat(parameters('vmNameSuffix'), 'VM', copyIndex(), '/OMS')]",
            "location": "[resourceGroup().location]",
            "copy": {
                "name": "[concat(parameters('vmNameSuffix'), 'VM', 'OMS')]",
                "count": "[parameters('instancecount')]"
            },
            "dependsOn": [
                "[concat('Microsoft.Compute/virtualMachines/', parameters('vmNameSuffix'), 'VM', copyIndex())]"
            ],
            "properties": {
                "publisher": "Microsoft.EnterpriseCloud.Monitoring",
                "type": "[variables('managementType').type]",
                "typeHandlerVersion": "1.0",
                "autoUpgradeMinorVersion": true,
                "settings": {
                    "workspaceId": "[reference(resourceId(parameters('workspaceResourceGroupName'), 'Microsoft.OperationalInsights/workspaces/', parameters('workspaceName')), '2015-11-01-preview').customerId]",
                    "azureResourceId": "[resourceId('Microsoft.Compute/virtualMachines/', concat(parameters('vmNameSuffix'), 'VM', copyIndex()))]"
                },
                "protectedSettings": {
                    "workspaceKey": "[listKeys(resourceId(parameters('workspaceResourceGroupName'),'Microsoft.OperationalInsights/workspaces/', parameters('workspaceName')), '2015-11-01-preview').primarySharedKey]"
                }
            }
        }