Configure network security groups on your Azure Local with PowerShell
Applies to: Azure Local, versions 23H2 and 22H2; Windows Server 2022, Windows Server 2019, Windows Server 2016
This article provides instructions for configuring network security groups (NSGs) to manage data traffic flow using Datacenter Firewall for Software Defined Networking (SDN) in Azure Local using Windows PowerShell. You enable and configure Datacenter Firewall by creating network security groups that get applied to a subnet or a network interface.
The example scripts in this article use Windows PowerShell commands exported from the NetworkController module. You can also use Windows Admin Center to configure and manage network security groups.
Configure Datacenter Firewall to allow all traffic
Once you deploy SDN, you should test for basic network connectivity in your new environment. To accomplish this, create a rule for Datacenter Firewall that allows all network traffic, without restriction.
Use the entries in the following table to create a set of rules that allow all inbound and outbound network traffic.
| Source IP | Destination IP | Protocol | Source Port | Destination Port | Direction | Action | Priority |
|---|---|---|---|---|---|---|---|
| * | * | All | * | * | Inbound | Allow | 100 |
| * | * | All | * | * | Outbound | Allow | 110 |
In this example, you create a network security group with two rules:
- AllowAll_Inbound - allows all network traffic to pass into the network interface where this network security group is configured.
- AllowAllOutbound - allows all traffic to pass out of the network interface. This network security group, identified by the resource ID "AllowAll-1" is now ready to be used in virtual subnets and network interfaces.
You can run this command from any computer that has access to the Network Controller REST endpoint. First, open a PowerShell session. In this example, use the Enter-PSSession cmdlet and replace <computer-name> with the name of the computer that has the Network Controller REST endpoint.
Enter-PSSession <computer-name>
Then, run the following script to create the network security group:
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Allow"
$ruleproperties.SourceAddressPrefix = "*"
$ruleproperties.DestinationAddressPrefix = "*"
$ruleproperties.Priority = "100"
$ruleproperties.Type = "Inbound"
$ruleproperties.Logging = "Enabled"
$aclrule1 = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule1.Properties = $ruleproperties
$aclrule1.ResourceId = "AllowAll_Inbound"
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Allow"
$ruleproperties.SourceAddressPrefix = "*"
$ruleproperties.DestinationAddressPrefix = "*"
$ruleproperties.Priority = "110"
$ruleproperties.Type = "Outbound"
$ruleproperties.Logging = "Enabled"
$aclrule2 = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule2.Properties = $ruleproperties
$aclrule2.ResourceId = "AllowAll_Outbound"
$acllistproperties = new-object Microsoft.Windows.NetworkController.AccessControlListProperties
$acllistproperties.AclRules = @($aclrule1, $aclrule2)
New-NetworkControllerAccessControlList -ResourceId "AllowAll" -Properties $acllistproperties -ConnectionUri <NC REST FQDN>
Note
The Windows PowerShell command reference for Network Controller is in the Network Controller cmdlets.
Use network security groups to limit traffic on a subnet
In this example, you create a network security group that prevents virtual machines (VMs) within the 192.168.0.0/24 subnet from communicating with each other. This type of network security group is useful for limiting the ability of an attacker to spread laterally within the subnet, while still allowing the VMs to receive requests from outside of the subnet, and to communicate with other services on other subnets.
| Source IP | Destination IP | Protocol | Source Port | Destination Port | Direction | Action | Priority |
|---|---|---|---|---|---|---|---|
| 192.168.0.1 | * | All | * | * | Inbound | Allow | 100 |
| * | 192.168.0.1 | All | * | * | Outbound | Allow | 101 |
| 192.168.0.0/24 | * | All | * | * | Inbound | Block | 102 |
| * | 192.168.0.0/24 | All | * | * | Outbound | Block | 103 |
| * | * | All | * | * | Inbound | Allow | 104 |
| * | * | All | * | * | Outbound | Allow | 105 |
The network security group created by the example script below, identified by the resource ID Subnet-192-168-0-0, can now be applied to a virtual network subnet that uses the "192.168.0.0/24" subnet address. Any network interface that is attached to that virtual network subnet automatically gets the above network security group rules applied.
The following is an example script to create this network security group using the Network Controller REST API:
import-module networkcontroller
$ncURI = "https://mync.contoso.local"
$aclrules = @()
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Allow"
$ruleproperties.SourceAddressPrefix = "192.168.0.1"
$ruleproperties.DestinationAddressPrefix = "*"
$ruleproperties.Priority = "100"
$ruleproperties.Type = "Inbound"
$ruleproperties.Logging = "Enabled"
$aclrule = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule.Properties = $ruleproperties
$aclrule.ResourceId = "AllowRouter_Inbound"
$aclrules += $aclrule
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Allow"
$ruleproperties.SourceAddressPrefix = "*"
$ruleproperties.DestinationAddressPrefix = "192.168.0.1"
$ruleproperties.Priority = "101"
$ruleproperties.Type = "Outbound"
$ruleproperties.Logging = "Enabled"
$aclrule = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule.Properties = $ruleproperties
$aclrule.ResourceId = "AllowRouter_Outbound"
$aclrules += $aclrule
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Deny"
$ruleproperties.SourceAddressPrefix = "192.168.0.0/24"
$ruleproperties.DestinationAddressPrefix = "*"
$ruleproperties.Priority = "102"
$ruleproperties.Type = "Inbound"
$ruleproperties.Logging = "Enabled"
$aclrule = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule.Properties = $ruleproperties
$aclrule.ResourceId = "DenySubnet_Inbound"
$aclrules += $aclrule
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Deny"
$ruleproperties.SourceAddressPrefix = "*"
$ruleproperties.DestinationAddressPrefix = "192.168.0.0/24"
$ruleproperties.Priority = "103"
$ruleproperties.Type = "Outbound"
$ruleproperties.Logging = "Enabled"
$aclrule = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule.Properties = $ruleproperties
$aclrule.ResourceId = "DenySubnet_Outbound"
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Allow"
$ruleproperties.SourceAddressPrefix = "*"
$ruleproperties.DestinationAddressPrefix = "*"
$ruleproperties.Priority = "104"
$ruleproperties.Type = "Inbound"
$ruleproperties.Logging = "Enabled"
$aclrule = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule.Properties = $ruleproperties
$aclrule.ResourceId = "AllowAll_Inbound"
$aclrules += $aclrule
$ruleproperties = new-object Microsoft.Windows.NetworkController.AclRuleProperties
$ruleproperties.Protocol = "All"
$ruleproperties.SourcePortRange = "0-65535"
$ruleproperties.DestinationPortRange = "0-65535"
$ruleproperties.Action = "Allow"
$ruleproperties.SourceAddressPrefix = "*"
$ruleproperties.DestinationAddressPrefix = "*"
$ruleproperties.Priority = "105"
$ruleproperties.Type = "Outbound"
$ruleproperties.Logging = "Enabled"
$aclrule = new-object Microsoft.Windows.NetworkController.AclRule
$aclrule.Properties = $ruleproperties
$aclrule.ResourceId = "AllowAll_Outbound"
$aclrules += $aclrule
$acllistproperties = new-object Microsoft.Windows.NetworkController.AccessControlListProperties
$acllistproperties.AclRules = $aclrules
New-NetworkControllerAccessControlList -ResourceId "Subnet-192-168-0-0" -Properties $acllistproperties -ConnectionUri $ncURI
Add a network security group to a network interface
Once you've created a network security group and assigned it to a virtual subnet, you might want to override that default network security group on the virtual subnet with a specific network security group for an individual network interface. Beginning in Windows Server 2019 Datacenter, you can apply specific network security groups directly to network interfaces attached to SDN logical networks, in addition to SDN virtual networks. If you have network security groups set on the virtual subnet connected to the network interface, both network security groups are applied, and the network interface network security groups are prioritized above the virtual subnet network security groups.
In this example, we demonstrate how to add a network security group to a virtual network.
Tip
It is also possible to add a network security group at the same time that you create the network interface.
Get or create the network interface to which you'll add the network security group.
$nic = get-networkcontrollernetworkinterface -ConnectionUri $uri -ResourceId "MyVM_Ethernet1"Get or create the network security group you'll add to the network interface.
$acl = get-networkcontrolleraccesscontrollist -ConnectionUri $uri -ResourceId "AllowAllACL"Assign the network security group to the AccessControlList property of the network interface.
$nic.properties.ipconfigurations[0].properties.AccessControlList = $aclAdd the network interface in Network Controller.
new-networkcontrollernetworkinterface -ConnectionUri $uri -Properties $nic.properties -ResourceId $nic.resourceid
Remove a network security group from a network interface
In this example, we show you how to remove a network security group from a network interface. Removing a network security group applies the default set of rules to the network interface. The default set of rules allows all outbound traffic but blocks all inbound traffic. If you want to allow all inbound traffic, you must follow the previous example to add a network security group that allows all inbound and all outbound traffic.
Get the network interface from which you'll remove the network security group.
$nic = get-networkcontrollernetworkinterface -ConnectionUri $uri -ResourceId "MyVM_Ethernet1"Assign $null to the AccessControlList property of the ipConfiguration.
$nic.properties.ipconfigurations[0].properties.AccessControlList = $nullAdd the network interface object in Network Controller.
new-networkcontrollernetworkinterface -ConnectionUri $uri -Properties $nic.properties -ResourceId $nic.resourceid
Firewall auditing
The firewall auditing capability for the Datacenter Firewall records any flow processed by SDN firewall rules. All network security groups that have logging enabled are recorded. The log files must be in a syntax that is consistent with the Azure Network Watcher flow logs. These logs can be used for diagnostics or archived for later analysis.
Here's a sample script to enable firewall auditing on host machines. Update the variables at the beginning and run this on an Azure Local instance with Network Controller deployed:
$logpath = "C:\test\log1"
$servers = @("sa18n22-2", "sa18n22-3", "sa18n22-4")
$uri = "https://sa18n22sdn.sa18.nttest.microsoft.com"
# Create log directories on the hosts
invoke-command -Computername $servers {
param(
$Path
)
mkdir $path -force
} -argumentlist $LogPath
# Set firewall auditing settings on Network Controller
$AuditProperties = new-object Microsoft.Windows.NetworkController.AuditingSettingsProperties
$AuditProperties.OutputDirectory = $logpath
set-networkcontrollerauditingsettingsconfiguration -connectionuri $uri -properties $AuditProperties -force | out-null
# Enable logging on each server
$servers = get-networkcontrollerserver -connectionuri $uri
foreach ($s in $servers) {
$s.properties.AuditingEnabled = @("Firewall")
new-networkcontrollerserver -connectionuri $uri -resourceid $s.resourceid -properties $s.properties -force | out-null
}
Once enabled, a new file appears in the specified directory on each host about once per hour. You should periodically process these files and remove them from the hosts. The current file has zero length and is locked until flushed at the next hour mark:
PS C:\test\log1> dir
Directory: C:\test\log1
Mode LastWriteTime Length Name
---- ------------- ------ ----
-a---- 7/19/2018 6:28 AM 17055 SdnFirewallAuditing.d8b3b697-5355-40e2-84d2-1bf2f0e0dc4a.20180719TL122803093.json
-a---- 7/19/2018 7:28 AM 7880 SdnFirewallAuditing.d8b3b697-5355-40e2-84d2-1bf2f0e0dc4a.20180719TL132803173.json
-a---- 7/19/2018 8:28 AM 7867 SdnFirewallAuditing.d8b3b697-5355-40e2-84d2-1bf2f0e0dc4a.20180719TL142803264.json
-a---- 7/19/2018 9:28 AM 10949 SdnFirewallAuditing.d8b3b697-5355-40e2-84d2-1bf2f0e0dc4a.20180719TL152803360.json
-a---- 7/19/2018 9:28 AM 0 SdnFirewallAuditing.d8b3b697-5355-40e2-84d2-1bf2f0e0dc4a.20180719TL162803464.json
These files contain a sequence of flow events, for example:
{
"records": [
{
"properties":{
"Version":"1.0",
"flows":[
{
"flows":[
{
"flowTuples":["1531963580,192.122.0.22,192.122.255.255,138,138,U,I,A"],
"portId":"9",
"portName":"7290436D-0422-498A-8EB8-C6CF5115DACE"
}
],
"rule":"Allow_Inbound"
}
]
},
"operationName":"NetworkSecurityGroupFlowEvents",
"resourceId":"a0a0a0a0-bbbb-cccc-dddd-e1e1e1e1e1e1",
"time":"20180719:L012620622",
"category":"NetworkSecurityGroupFlowEvent",
"systemId":"d8b3b697-5355-40e2-84d2-1bf2f0e0dc4a"
},
Note, logging takes place only for rules that have Logging set to Enabled, for example:
{
"Tags": null,
"ResourceRef": "/accessControlLists/AllowAll",
"InstanceId": "4a63e1a5-3264-4986-9a59-4e77a8b107fa",
"Etag": "W/\"1535a780-0fc8-4bba-a15a-093ecac9b88b\"",
"ResourceMetadata": null,
"ResourceId": "AllowAll",
"Properties": {
"ConfigurationState": null,
"ProvisioningState": "Succeeded",
"AclRules": [
{
"ResourceMetadata": null,
"ResourceRef": "/accessControlLists/AllowAll/aclRules/AllowAll_Inbound",
"InstanceId": "ba8710a8-0f01-422b-9038-d1f2390645d7",
"Etag": "W/\"1535a780-0fc8-4bba-a15a-093ecac9b88b\"",
"ResourceId": "AllowAll_Inbound",
"Properties": {
"Protocol": "All",
"SourcePortRange": "0-65535",
"DestinationPortRange": "0-65535",
"Action": "Allow",
"SourceAddressPrefix": "*",
"DestinationAddressPrefix": "*",
"Priority": "101",
"Description": null,
"Type": "Inbound",
"Logging": "Enabled",
"ProvisioningState": "Succeeded"
}
},
{
"ResourceMetadata": null,
"ResourceRef": "/accessControlLists/AllowAll/aclRules/AllowAll_Outbound",
"InstanceId": "068264c6-2186-4dbc-bbe7-f504c6f47fa8",
"Etag": "W/\"1535a780-0fc8-4bba-a15a-093ecac9b88b\"",
"ResourceId": "AllowAll_Outbound",
"Properties": {
"Protocol": "All",
"SourcePortRange": "0-65535",
"DestinationPortRange": "0-65535",
"Action": "Allow",
"SourceAddressPrefix": "*",
"DestinationAddressPrefix": "*",
"Priority": "110",
"Description": null,
"Type": "Outbound",
"Logging": "Enabled",
"ProvisioningState": "Succeeded"
}
}
],
"IpConfigurations": [
],
"Subnets": [
{
"ResourceMetadata": null,
"ResourceRef": "/virtualNetworks/10_0_1_0/subnets/Subnet1",
"InstanceId": "00000000-0000-0000-0000-000000000000",
"Etag": null,
"ResourceId": null,
"Properties": null
}
]
}
}
Next steps
For related information, see: