Tag: Networking

Referencing Private Endpoint IP Addresses In Terraform

It is possible to dynamically retrieve the resulting IP address of an Azure Private Endpoint and use it in other resources in Terraform. This post will show you how.

Scenario

You are building some PaaS resources using Private Endpoints. You have no idea what the IP addresses are going to be. But you need to use those IP addresses elsewhere in your Terraform code, for example in an NSG rule. How do you get the IP addresses?

Find The Properties

The trick for this is to use the terraform state command. In my case, I deployed a Cosmos DB resource using azurerm_private_endpoint.cosmosdb-account1. To view the state of the resource, I can run:

terraform state show azurerm_private_endpoint.cosmosdb-account1

That outputs a bunch of code:

Terraform state of a Cosmos DB resource

You can think of the exposed state as a description of the resource the moment after it was deployed. Everything in that state is addressable. A common use might be to refer to the resource ID (azurerm_private_endpoint.cosmosdb-account1.id) or resource name (azurerm_private_endpoint.cosmosdb-account1.name) properties. But you can also get other properties that you don’t know in advance.

The Solution

Take another look at the above diagram. There is an array property called private_dns_zone_configs that has one item. We can address this property as azurerm_private_endpoint.cosmosdb-account1.private_dns_zone_configs[0].

In there there is another array property, with two items, called record_sets. There is one record set per IP address created for this private endpoint. We can address these properties as azurerm_private_endpoint.cosmosdb-account1.private_dns_zone_configs[0].record_sets[0] and azurerm_private_endpoint.cosmosdb-account1.private_dns_zone_configs[0].record_sets[1].

Cosmos DB creates a private endpoint with multiple different IP addresses. I deliberately chose Cosmos DB for this example because it shows a more complex probelm and solution, demonstrating a little bit more of the method.

Dig into record_sets and you’ll find an array property called ip_addresses with 1 item. If I want the two IP addresses of this private endpoint then I will use: azurerm_private_endpoint.cosmosdb-account1.private_dns_zone_configs[0].record_sets[0].ip_addresses[0] and azurerm_private_endpoint.cosmosdb-account1.private_dns_zone_configs[0].record_sets[1].ip_addresses[0].

Using the Addresses

destination_address_prefixes = [
 azurerm_private_endpoint.cosmosdb-account1.private_dns_zone_configs[0].record_sets[0].ip_addresses[0], // Cosmos DB Private Endpoint IP 1
 azurerm_private_endpoint.cosmosdb-account1.private_dns_zone_configs[0].record_sets[1].ip_addresses[0] // Cosmos DB Private Endpoint IP 2
 ]                       
}

And now I have code that will deploy an NSG rule with the correct destination IP address(es) of my private endpoint without knowing them. And even better, if something causes the IP address(es) to change, I can rerun my code without changing it, and the rules will automatically update.

Azure Firewall DevSecOps in Azure DevOps

In this post, I will share the details for granting the least-privilege permissions to GitHub action/DevOps pipeline service principals for a DevSecOps continuous deployment of Azure Firewall.

Quick Refresh

I wrote about the design of the solution and shared the code in my post, Enabling DevSecOps with Azure Firewall. There I explained how you could break out the code for the rules of a workload and manage that code in the repo for the workload. Realistically, you would also need to break out the gateway subnet route table user-defined route (legacy VNet-based hub) and the VNet peering connection. All the code for this is shared on GitHub – I did update the repo with some structure and with working DevOps pipelines.

This Update

There were two things I wanted to add to the design:

  • Detailed permissions for the service principal used by the workload DevOps pipeline, limiting the scope of change that is possible in the hub.
  • DevOps pipelines so I could test the above.

The Code

You’ll find 3 folders in the Bicep code now:

  • hub: This deploys a (legacy) VNet-based hub with Azure Firewall.
  • customRoles: 4 Azure custom roles are defined. This should be deployed after the hub.
  • spoke1: This contains the code to deploy a skeleton VNet-based (spoke) workload with updates that are required in the hub to connect the VNet and route ingress on-prem traffic through the firewall.

DevOps Pipelines

The hub and spoke1 folders each contain a folder called .pipelines. There you will find a .yml file to create a DevOps pipeline.

The DevOps pipeline uses Azure CLI tasks to:

  • Select the correct Azure subscription & create the resource group
  • Deploy each .bicep file.

My design uses 1 sub for the hub and 1 sub for the workload. You are not glued to this bu you would need to make modifications to how you configure the service principal permissions (below).

To use the code:

  1. Create a repo in DevOps for (1 repo) hub and for (1 repo) spoke1 and copy in the required code.
  2. Create service principals in Azure AD.
  3. Grant the service principal for hub owner rights to the hub subscription.
  4. Grant the service principal for the spoke owner rights to the spoke subscription.
  5. Create ARM service connections in DevOps settings that use the service principals. Note that the names for these service connections are referred to by azureServiceConnection in the pipeline files.
  6. Update the variables in the pipeline files with subscription IDs.
  7. Create the pipelines using the .yml files in the repos.

Don’t do anything just yet!

Service Principal Permissions

The hub service principal is simple – grant it owner rights to the hub subscription (or resource group).

The workload is where the magic happens with this DevSecOps design. The workload updates the hub suing code in the workload repo that affects the workload:

  • Ingress route from on-prem to the workload in the hub GatewaySubnet.
  • The firewall rules for the workload in the hub Azure Firewall (policy) using a rules collection group.
  • The VNet peering connection between the hub VNet and the workload VNet.

That could be deployed by the workload DevOps pipeline that is authenticated using the workload’s service principal. So that means the workload service principal must have rights over the hub.

The quick solution would be to grant contributor rights over the hub and say “we’ll manage what is done through code reviews”. However, a better practice is to limit what can be done as much as possible. That’s what I have done with the customRoles folder in my GitHub share.

Those custom roles should be modified to change the possible scope to the subscription ID (or even the resource group ID) of the hub deployment. There are 4 custom roles:

  • customRole-ArmValidateActionOperator.json: Adds the CUSTOM – ARM Deployment Operator role, allowing the ARM deployment to be monitored and updated.
  • customRole-PeeringAdmin.json: Adds the CUSTOM – Virtual Network Peering Administrator role, allowing a VNet peering connection to be created from the hub VNet.
  • customRole-RoutesAdmin.json: Adds the CUSTOM – Azure Route Table Routes Administrator role, allowing a route to be added to the GatewaySubnet route table.
  • customRole-RuleCollectionGroupsAdmin.json: Adds the CUSTOM – Azure Firewall Policy Rule Collection Group Administrator role, allowing a rules collection group to be added to an Azure Firewall Policy.

Deploy The Hub

The hub is deployed first – this is required to grant the permissions that are required by the workload’s service principal.

Grant Rights To Workload Service Principals

The service principals for all workloads will be added to an Azure AD group (Workloads Pipeline Service Principals in the above diagram). That group is nested into 4 other AAD security groups:

  • Resource Group ARM Operations: This is granted the CUSTOM – ARM Deployment Operator role on the hub resource group.
  • Hub Firewall Policy: This is granted the CUSTOM – Azure Firewall Policy Rule Collection Group Administrator role on the Azure Firewalll Policy that is associated with the hub Azure Firewall.
  • Hub Routes: This is granted the CUSTOM – Azure Route Table Routes Administrator role on the GattewaySubnet route table.
  • Hub Peering: This is granted the CUSTOM – Virtual Network Peering Administrator role on the hub virtual network.

Deploy The Workload

The workload now has the required permissions to deploy the workload and make modifications in the hub to connect the hub to the outside world.

Azure Virtual WAN ARM – The Resources

In this post, I will explain the types of resources used in Azure Virtual WAN and the nature of their relationships.

Note, I have not included any content on the recently announced preview of third-party NVAs. I have not seen any materials on this yet to base such a post on and, being honest, I don’t have any use-cases for third-party NVAs.

As you can see – there are quite a few resources involved … and some that you won’t see listed at all because of the “appliance-like” nature of the deployment. I have not included any detail on spokes or “branch offices”, which would require further resources. The below diagram is enough to get a hub operational and connected to on-premises locations and spoke virtual networks.

The Virtual WAN – Microsoft.Network/virtualWans

You need at least one Virtual WAN to be deployed. This is what the hub will connect to, and you can connect many hubs to a common Virtual WAN to get automated any-to-any connectivity across the Microsoft physical WAN.

Surprisingly, the resource is deployed to an Azure region and not as a global resource, such as other global resources such as Traffic Manager or Azure DNS.

The Virtual Hub – Microsoft.Network/virtualHubs

Also known as the hub, the Virtual Hub is deployed once, and once only, per Azure region where you need a hub. This hub replaces the old hub virtual network (plus gateway(s), plus firewall, plus route tables) deployment you might be used to. The hub is deployed as a hidden resource, managed through the Virtual WAN in the Azure Portal or via scripting/ARM.

The hub is associated with the Virtual WAN through a virtualWAN property that references the resource ID of the virtualWans resource.

In a previous post, I referred to a chicken & egg scenario with the virtualHubs resource. The hub has properties that point to the resource IDs of each deployed gateway:

  • vpnGateway: For site-to-site VPN.
  • expressRouteGateway: For ExpressRoute circuit connectivity.
  • p2sVpnGateway: For end-user/device tunnels.

If you choose to deploy a “Secured Virtual Hub” there will also be a property called azureFirewall that will point to the resource ID of an Azure Firewall with the AZFW_Hub SKU.

Note, the restriction of 1 hub per Azure region does introduce a bottleneck. Under the covers of the platform, there is actually a virtual network. The only clue to this network will be in the peering properties of your spoke virtual networks. A single virtual network can have, today, a maximum of 500 spokes. So that means you will have a maximum of 500 spokes per Azure region.

Routing Tables – Microsoft.Network/virtualHubs/hubRouteTables & Microsoft.Network/virtualHubs/routeTables

These are resources that are used in custom routing, a recently announced as GA feature that won’t be live until August 3rd, according to the Azure Portal. The resource control the flows of traffic in your hub and spoke architecture. They are child-resources of the virtualHubs resource so no references of hub resource IDs are required.

Azure Firewall – Microsoft.Network/azureFirewalls

This is an optional resource that is deployed when you want a “Secured Virtual Hub”. Today, this is the only way to put a firewall into the hub, although a new preview program should make it possible for third-parties to join the hub. Alternatively, you can use custom routing to force north-south and east-west traffic through an NVA that is running in a spoke, although that will double peering costs.

The Azure Firewall is deployed with the AZFW_Hub SKU. The firewall is not a hidden resource. To manage the firewall, you must use an Azure Firewall Policy (aka Azure Firewall Manager). The firewall has a property called firewallPolicy that points to the resource ID of a firewallPolicies resource.

Azure Firewall Policy – Microsoft.Network/firewallPolicies

This is a resource that allows you to manage an Azure Firewall, in this case, an AZFW_Hub SKU of Azure Firewall. Although not shown here, you can deploy a parent/child configuration of policies to manage firewall configurations and rules in a global/local way.

VPN Gateway – Microsoft.Network/vpnGateways

This is one of 3 ways (one, two or all three at once) that you can connect on-premises (branch) sites to the hub and your Azure deployment(s). This gateway provides you with site-to-site connectivity using VPN. The VPN Gateway uses a property called virtualHub to point at the resource ID of the associated hub or virtualHubs resource. This is a hidden resource.

Note that the virtualHubs resource must also point at the resource ID of the VPN gateway resource ID using a property called vpnGateway.

ExpressRoute Gateway – Microsoft.Network/expressRouteGateways

This is one of 3 ways (one, two or all three at once) that you can connect on-premises (branch) sites to the hub and your Azure deployment(s). This gateway provides you with site-to-site connectivity using ExpressRoute. The ExpressRoute Gateway uses a property called virtualHub to point at the resource ID of the associated hub or virtualHubs resource. This is a hidden resource.

Note that the virtualHubs resource must also point at the resource ID of the ExpressRoute gateway resource ID using a property called p2sGateway.

Point-to-Site Gateway – Microsoft.Network/p2sVpnGateways

This is one of 3 ways (one, two or all three at once) that you can connect on-premises (branch) sites to the hub and your Azure deployment(s). This gateway provides users/devices with connectivity using VPN tunnels. The Point-to-Site Gateway uses a property called virtualHub to point at the resource ID of the associated hub or virtualHubs resource. This is a hidden resource.

The Point-to-Site Gateway inherits a VPN configuration from a VPN configuration resource based on Microsoft.Network/vpnServerConfigurations, referring to the configuration resource by its resource ID using a property called vpnServerConfiguration.

Note that the virtualHubs resource must also point at the resource ID of the Point-to-Site gateway resource ID using a property called p2sVpnGateway.

VPN Server Configuration – Microsoft.Network/vpnServerConfigurations

This configuration for Point-to-Site VPN gateways can be seen in the Azure WAN and is intended as a shared configuration that is reusable with more than one Point-to-Site VPN Gateway. To be honest, I can see myself using it as a per-region configuration because of some values like DNS servers and RADIUS servers that will probably be placed per-region for performance and resilience reasons. This is a hidden resource.

The following resources were added on 22nd July 2020:

VPN Sites – Microsoft.Network/vpnSites

This resource has a similar purpose to a Local Network Gateway for site-to-site VPN connections; it describes the on-premises location, AKA “branch office”.  A VPN site can be associated with one or many hubs, so it is actually connected to the Virtual WAN resource ID using a property called virtualWan. This is a hidden resource.

An array property called vpnSiteLinks describes possible connections to on-premises firewall devices.

VPN Connections – Microsoft.Network/vpnGateways/vpnConnections

A VPN Connections resource associates a VPN Gateway with the on-premises location that is described by an associated VPN Site. The vpnConnections resource is a child resource of vpnGateways, so there is no actual resource; the vpnConnections resource takes its name from the parent VPN Gateway, and the resource ID is an extension of the parent VPN Gateway resource ID.

By necessity, there is some complexity with this resource type. The remoteVpnSite property links the vpnConnections resource with the resource ID of a VPN Site resource. An array property, called vpnSiteLinkConnections, is used to connect the gateway to the on-premises location using 1 or 2 connections, each linking from vpnSiteLinkConnections to the resource/property ID of 1 or 2 vpnSiteLinks properties in the VPN Site. With one site link connection, you have a single VPN tunnel to the on-premises location. With 2 link connections, the VPN Gateway will take advantage of its active/active configuration to set up resilient tunnels to the on-premises location.

Virtual Network Connections – Microsoft.Network/virtualHubs/hubVirtualNetworkConnections

The purpose of a hub is to share resources with spoke virtual networks. In the case of the Virtual Hub, those resources are gateways, and maybe a firewall in the case of Secured Virtual Hub. As with a normal VNet-based hub & spoke, VNet peering is used. However, the way that VNet peering is used changes with the Virtual Hub; the deployment is done using the hub/VirtualNetworkConnections child resource, whose parent is the Virtual Hub. Therefore, the name and resource ID are based on the name and resource ID of the Virtual Hub resource.

The deployment is rather simple; you create a Virtual Network Connection in the hub specifying the resource ID of the spoke virtual network, using a property called remoteVirtualNetwork. The underlying resource provider will initiate both sides of the peering connection on your behalf – there is no deployment required in the spoke virtual network resource. The Virtual Network Connection will reference the Hub Route Tables in the hub to configure route association and propagation.

More Resources

There are more resources that I’ve yet to document, including:

Connecting Azure Hub-And-Spoke Architectures Together

In this post, I will explain how you can connect multiple Azure hub-and-spoke (virtual data centre) deployments together using Azure networking, even across different Azure regions.

There is a lot to know here so here is some recommended reading that I previously published:

If you are using Azure Virtual WAN Hub then some stuff will be different and that scenario is not covered fully here – Azure Virtual WAN Hub has a preview (today) feature for Any-to-Any routing.

The Scenario

In this case, there are two hub-and-spoke deployments:

  • Blue: Multiple virtual networks covered by the CIDR of 10.1.0.0/16
  • Green: Another set of multiple virtual networks covered by the CIDR of 10.2.0.0/16

I’m being strategic with the addressing of each hub-and-spoke deployment, ensuring that a single CIDR will include the hub and all spokes of a single deployment – this will come in handy when we look at User-Defined Routes.

Either of these hub-and-spoke deployments could be in the same region or even in different Azure regions. It is desired that if:

  • Any spoke wishes to talk to another spoke it will route through the local firewall in the local hub.
  • All traffic coming into a spoke from an outside source, such as the other hub-and-spoke, must route through the local firewall in the local hub.

That would mean that Spoke 1 must route through Hub 1 and then Hub 2 to talk to Spoke 4. The firewall can be a third-party appliance or the Azure Firewall.

Core Routing

Each subnet in each spoke needs a route to the outside world (0.0.0.0/0) via the local firewall. For example:

  • The Blue firewall backend/private IP address is 10.1.0.132
  • A Route Table for each subnet is created in the Blue deployment and has a route to 0.0.0.0/0 via a virtual appliance with an IP address of 10.1.0.132
  • The Greenfirewall backend/private IP address is 10.2.0.132
  • A Route Table for each subnet is created in the Green deployment and has a route to 0.0.0.0/0 via a virtual appliance with an IP address of 10.2.0.132

Note: Some network-connected PaaS services, e.g. API Management or SQL Managed Instance, require additional routes to the “control plane” that will bypass the local firewall.

Site-to-Site VPN

In this scenario, the organisation is connecting on-premises networks to 1 or more of the hub-and-spoke deployments with a site-to-site VPN connection. That connection goes to the hub of Blue and to Green hubs.

To connect Blue and Green you will need to configure VNet Peering, which can work inside a region or across regions (using Microsoft’s low latency WAN, the second-largest private WAN on the planet). Each end of peering needs the following settings (the names of the settings change so I’m not checking their exact naming):

  • Enabled: Yes
  • Allow Transit: Yes
  • Use Remote Gateway: No
  • Allow Gateway Sharing: No

Let’s go back and do some routing theory!

That peering connection will add a hidden Default (“system”) route to each subnet in the hub subnets:

  • Blue hub subnets: A route to 10.2.0.0/24
  • Green hub subnets: A route to 10.1.0.0/24

Now imagine you are a packet in Spoke 1 trying to get to Spoke 4. You’re sent to the firewall in Blue Hub 1. The firewall lets the traffic out (if a rule allows it) and now the packet sits in the egress/frontend/firewall subnet and is trying to find a route to 10.2.2.0/24. The peering-created Default route covers 10.2.0.0/24 but not the subnet for Spoke 4. So that means the default route to 0.0.0.0/0 (Internet) will be used and the packet is lost.

To fix this you will need to add a Route Table to the egress/frontend/firewall subnet in each hub:

  • Blue firewall subnet Route Table: 10.2.0.0/16 via virtual appliance 10.2.0.132
  • Red firewall subnet Route Table: 10.1.0.0/16 via virtual appliance 10.1.0.132

Thanks to my clever addressing of each hub-and-spoke, a single route will cover all packets leaving Blue and trying to get to any spoke in Red and vice-versa.

ExpressRoute

Now the customer has decided to use ExpressRoute to connect to Azure – Sweet! But guess what – you don’t need 1 expensive circuit to each hub-and-spoke.

You can share a single circuit across multiple ExpressRoute gateways:

  • ExpressRoute Standard: Up to 10 simultaneous connections to Virtual Network Gateways in 1+ regions in the same geopolitical region.
  • ExpressRoute Premium: Up to 100 simultaneous connections to Virtual Network Gateways in 1+ regions in any geopolitical region.

FYI, ExpressRoute connections to the Azure Virtual WAN Hub must be of the Premium SKU.

ExpressRoute is powered by BGP. All the on-premises routes that are advertised propagate through the ISP to the Microsoft edge router (“meet-me”) in the edge data centre. For example, if I want an ExpressRoute circuit to Azure West Europe (Middenmeer, Netherlands – not Amsterdam) I will probably (not always) get a circuit to the POP or edge data centre in Amsterdam. That gets me a physical low-latency connection onto the Microsoft WAN – and my BGP routes get to the meet-me router in Amsterdam. Now I can route to locations on that WAN. If I connect a VNet Gateway to that circuit to Blue in Azure West Europe, then my BGP routes will propagate from the meet-me router to the GatewaySubnet in the Blue hub, and then on to my firewall subnet.

BGP propagation is disabled in the spoke Route Tables to ensure all outbound flows go through the local firewall.

But that is not the extent of things! The hub-and-spoke peering connections allow Gateway Sharing from the hub and Use Remote Gateway from the spoke. With that configuration, BGP routes to the spoke get propagated to the GatewaySubnet in the hub, then to the meet-me router, through the ISP and then to the on-premises network. This is what our solution is based on.

Let’s imagine that the Green deployment is in North Europe (Dublin, Ireland). I could get a second ExpressRoute connection but:

  • That will add cost
  • Not give me the clever solution that I want – but I could work around that with ExpressRoute Global Reach

I’m going to keep this simple – by the way, if I wanted Green to be in a different geopolitical region such as East US 2 then I could use ExpressRoute Premium to make this work.

In the Green hub, the Virtual Network Gateway will connect to the existing ExpressRoute circuit – no more money to the ISP! That means Green will connect to the same meet-me router as Blue. The on-premises routes will get into Green the exact same way as with Blue. And the routes to the Green spokes will also propagate down to on-premises via the meet-me router. That meet-me router knows all about the subnets in Blue and Green. And guess what BGP routers do? They propagate – so, the routes to all of the Blue subnets propagate to Green and vice-versa with the next hop (after the Virtual Network Gateway) being the meet-me router. There are no Route Tables or peering required in the hubs – it just works!

Now the path from Blue Spoke 1 to Green Spoke 4 is Blue Hub Firewall, Blue Virtual Network Gateway, <the Microsoft WAN>, Microsoft (meet-me) Router, <the Microsoft WAN>, Green Virtual Network Gateway, Green Hub Firewall, Green Spoke 4.

There are ways to make this scenario more interesting. Let’s say I have an office in London and I want to use Microsoft Azure. Some stuff will reside in UK South for compliance or performance reasons. But UK South is not a “hero region” as Microsoft calls them. There might be more advanced features that I want to use that are only in West Europe. I could use two ExpressRoute circuits, one to UK South and one to West Europe. Or I could set up a single circuit to London to get me onto the Microsoft WAN and connected this circuit to both of my deployments in UK South and West Europe. I have a quicker route going Office > ISP > London edge data center > Azure West Europe than from Office > ISP > Amsterdam edge data center > Azure West Europe because I have reduced the latency between me and West Europe by reducing the length of the ISP circuit and using the more-direct Microsoft WAN. Just like with Azure Front Door, you want to get onto the Microsoft WAN as quickly as possible and let it get you to your destination as quickly as possible.

I’m Presenting Two Sessions At NIC 20/20 Vision in Oslo

I will be presenting two Azure sessions at the (NICCONF) NIC 20/20 Vision conference in Oslo on February 6th.

The content I’m presenting on is inspired by the work I have been doing with Innofactor Norway for customers in Norway. So it will be kind of cool to stand (once again) on a stage in Oslo and share what I’ve learned. I have two sessions on the afternoon of the 6th.

Secure Azure Network Architecture

Azure networking & security has become my focus area. I enjoy the organic nature of how Azure’s software-defined networking functions. I enjoy the scale, the possibilities, and the variety of options. And most of all, I appreciate how the near-universally overlooked fundamentals play a bigger role in network security than people realise. It’s a huge area to cover, but I will do my best in the hour that I have:

This session will walk you through the components of Azure network security, and how to architect a secure network for Azure virtual machines or platform services, including VNets, network security groups, routing tables, VNet peering, web application gateway, DDoS protection, and firewall appliances.

Auditing Azure – Compliance, Oversight, Governance, and Protection

An important part of governance is recording what is going on in Azure and being able to retain, query, and report on that data. This is an area I had a cool solution for this time last year, but Microsoft blew that up. Recently I revisited this space and found cool new things that I could do. And in preparing for this session, I found more stuff that I could talk about. I’ve enjoyed preparing this session and it has contributed back to my work. This session is late in the day for most Norwegians, but I hope that attendees stick around.

Auditing isn’t the most glamorous subject, but in a self-service environment, it becomes important to protect assets, the company, and even your job. In this session, you’ll learn how Azure provides auditing functionality that you can query, report on, and store securely for as long as you need it in cost-efficient ways.

Hopefully, I will see some of you there at the event!

Back Teaching – Implementing Secure Azure Networks

After a quiet 2019, I am getting back into Azure training starting in March in Brussels, Belgium, with a new hands-on course called Implementing Secure Azure Networks.

2019 was a year of (good) upheaval. I started a new job with big responsibilities and a learning curve. Family-wise, we had a lot of good things going on. So I decided to put our (my wife and I) Cloud Mechanix training on the shelf for a while. All last year, I’ve been putting a lot of cool Azure networking & security things into practice with larger enterprises so I’ve been learning … new things, good practices, what works, what doesn’t, and so on. That put the seed into my head for the next class that I would write. Then along came Workshop Summit and asked if I would like to submit a 1-day practical training course. So I did, and they accepted.

The Course

Security is always number 1 or 2 in any survey on the fears of cloud computing. Networking in The Cloud is very different to traditional physical networking … but in some ways it is quite similar. The goals of this workshop are:

  • To teach you the fundamentals, the theory, of how Azure networking functions so you can understand the practical design and application
  • Do hands-on deployments of secure networks

As a result, this workshop takes you all the way back to the basics of Azure networking so you really understand the “wiring” of a secure network in the cloud. Only with that understanding do you understand that small is big. The topics covered in this class will secure small/mid businesses, platform deployments that require regulatory compliance, and large enterprises:

  • The Microsoft global network
  • Availability & SLA
  • Virtual network basics
  • Virtual network adapters
  • Peering
  • Service endpoints
  • Private Link & Private Endpoints
  • Public IP Addresses
  • VNet gateways: VPN & ExpressRoute
  • Network Security Groups
  • Application Firewall
  • Route Tables
  • Third-Party Firewalls
  • Azure Firewall
  • Architectures

Attendees will require an Azure subscription capable of deploying multiple 4 x single-core virtual machines, 1 x Azure Firewall, 1 x Web Application Gateway, and 1 x per GB Log Analytics Workspace for 1 day.

When

Tuesday, 3rd March

Where

Venue: the Hackages Lab, located at Avenue des Arts 3-4-5 in Brussels

Organisers & Registration

This event is being run by The Workshop Summit. All registration and payments are handled by that event.

Who Should Attend

You don’t need to be a networking guru to attend this class. I always start my Azure networking training by explaining that I have never set up a VLAN; I’m proud of that! But I can out-network most people in Azure. Azure networking requires some learning, especially to do it correctly and securely, and that starts with re-learning some fundamentals. Those who understand basic concepts like a route, a firewall rule, network addressing (CIDR blocks), and so on will do fine on this course.

Who will benefit? Anyone planning on working with Azure. If you’re the person building the first “landing zone” for a migration, setting up the infrastructure for a new cloud-based service, working with IaaS VMs or platform (PaaS – yes network security plays a big role here!) then this course is for you. Get this stuff right early on and you’ll look like a genius. Or maybe you’ve already got an infrastructure and it’s time to learn how to mature it? We will start with the basics, cover them deeply, and then dive deep, focusing on security in ways that a typical Azure introduction course cannot do.

Microsoft Ignite 2019 – Deliver Highly Available Secure Web Application Gateway and Web Application Firewall

Speaker:

  • Amit Srivastava, Principal Program Manager, Microsoft

Mission Critical HTTP Applications

  • Always On
  • Secure
  • Scalable
  • Telemetry
  • Polygot – variety of backed, IaaS, PaaS, on-prem

Many things to think about.

What Azure Pieces Can We Use?

  • WAG
  • AFD
  • CDN
  • WAF
  • Azure Load Balancer
  • Azure Traffic Manager

WAG

Regional ADS as a service. A full reverse proxy. It terminates the incoming connection and creates a new one to the web server.

  • Platform managed: built-in HA and sclability
  • Layer 7 load balancing: URL path, host based, round robin, session affinity, redirection
  • Security and SSL management: WAF, SSL Offload, SSL re-encryption, SSL policy
  • Public or ILB: Public internet, internal or both.
  • Flexible backends: VMs, VMSS, AKS, public IP, cloud services, ALB/ILB, On-premises
  • Rich diagnostics: Azure monitor, log analytics, network watcher, RHC, more

Standard v2 SKU in GA

  • Available in 26 regions
  • Built-in zone redundancy
  • Static VIP
  • HTTP header/cookies insertion/modification
  • Increased scale limits 20 -> 100 listeners
  • Key vault integration and autorenewal of SSL certs (GA)
  • AKS ingress controller (GA)

Autoscaling and performance improvements:

  • Grow and shrink based on app traffic requirements
  • 5 x better SSL offloads performance
    • 500-50,000 connections/sec with RSA 2048 bit certs
    • 30,000, 3,000,000 persistent connections
    • 2,500 – 250,0000 HTTP req/sec
  • 75% reduction in provisioning time ~5mins

Key Vault Integration in v2 GA

  • Front end TLS cert integrated with Azure Key Vault
  • Utilizes user-assigned management identity for access control on key vault
  • Use certificate or secrets on Key Vault
  • Pools every 4 hours to enable automatic cert renewal – you can force a poll if you need to
  • Manual override or specific certificate version retrieval

WAG v2 Header Rewrites

  • Manipulate request and response headers and cookies
    • Strip port from x-forwarded-for header
    • Add security headers like HSTS and X-XSS-Protection
    • Common header manipulation ex: HOST, SERVER
  • Conditional header rewrites … something

Ingress Controller

  • Ingress controller for 1+ AKS clusters at one time
  • Deployed using HELM – newer easier options by EOY
  • Utilized pod-AAD for ARM authentication
  • Tighter integration with AKS add-on support upcoming
  • Supports URI-path based, host based, SSL termination, SSL re-encryption, redirection, custom health probes, draining, cookie affinity.
  • Support for Let’s Encrypt provided TLS certs
  • WAF fully supported with custom listener policies
  • Support for multiple AKS as backend
  • Support for mixed mode- both AKS and other backend types on the same application gateway.

http://aka.ms/appgawks

Application Gateway Wildcard Listener

  • Managed preview
  • Support for wildcard characters in listener host name
  • Supports * and ? characters in host name
  • Associate wildcard or SAN certs to serve HTTPS

Telemetry Enhancements

  • GA
  • Diagnostics Log Enhancements
    • TLS protocol version, cipher spec selected.
    • Backend target server, response code, latency.
  • Metrics Enahncements
    • Backend response status code
    • RPS/healthy node
    • End-to-end latency
    • Backend latency
    • Backend connect, first byte, and last byte latency.

Azure Monitor Insights for Application Gateway

  • Public Preview
  • Sign health and metric console for your entire cloud network#
  • No agent/configuration required
  • Visualize the structure and functional dependencies
  • More

AKS Demo

He loads a Helm YAML config to the AKS cluster. Now the AKS cluster can configure listers, backend pools, rules, etc for the containers/services running on the cluster. Pretty cool.

Azure WAF

Cloud native WAF

  • Unified WAF offering
    • Protect your apps at network edge or in region uniformly
  • Public preview:
    • Microsoft threat intelligence
      • Protect apps against automated attacks
      • Manage good/bad bots with Azure BotManager RuleSet
    • Site and URI pathc specific WAF policies
      • Customise WAF policies at regional WAF for finer grained protection at each host/listener or URI path level
    • Geo-filtering on regional WAF

WAF

  • HA, scalable fully platform managed
  • Auto-scaling support
  • New RuleSet CRS 3.1 added, will soon be the default
  • Integration with Azure Sentinel SIEM
  • Performance and concurrency enhancements
  • More

WAF Policy Enhancements

  • Assign different policies to different sites behind the same WAF
  • Increased configurability
  • Per-URI policy

Geo Filtering Public Preview

  • Block, allow, log countries.
  • Easily configurable in WAF policy
  • Geo data refreshed weekly

Only in special Portal URI at the moment – normal Azure Portal soon.

Bot Protection (Public Preview)

  • Stuff

Microsoft Ignite 2019 – Delivering Services Privately in Your VNet with Azure Private Link

Speakers:

  • Narayan Annamalai, Group Program Manager, Microsoft
  • Sumeet Mittal, Senior Program Manager, Microsoft

Private PaaS

We’ve been using Service Endpoint in addition with ACLs on the PaaS services. But this doesn’t provide an IP on the subnet. NSGs still need to allow access to all IPs of that PaaS service, e.g. all storage accounts.

Private Link maps your PaaS service into a subnet via an IP address. A private endpoint is effectively a NIC that connects to an instance of the PaaS.

Data Exfiltration Protection

Only a specific PaaS instance is mapped into your VNet subnet. So only one storage account, for example, joins your subnet via the Private Endpoint.  Trying to by pass this using clever tricks, e.g. DNS, will not work because the packets are dropped – this is data exfiltration protection.

Other clouds map an entire service, e.g. all storage accounts, to an IP address. Azure Private Endpoint maps a specific instance, e.g. a single storage account, to an IP address.

Secure Connectivity From On-Premises

Before:

  • You connect to PaaS via public DNS
  • The name resolves to the service public IP address
  • If VPN/no connection, you route over Internet. If ExpressRoute with Microsoft Peering enabled, you route over the ExpressRoute circuit.

After:

  • You connect to the PaaS service using a new DNS name
  • You route over the network connection (VPN/ER) to the VNet/subnet.
  • You connect to the Private Endpoint private IP address for the instance of the PaaS service.

Not Just For PaaS

Not just a new feature. It’s a new platform ability.

You can build your own services too, behind Standard Tier Load Balancer, and present the services to other VNets/tenants via Azure Private Link.

Private Link is the product. Private Endpoint is how you use it.

There are three kinds of Private Link:

  • PaaS
  • Other partner services (Snowflake)
  • Consume your own services

Simple Example – VM to Storage Account

VM sends a packet to Blob1.core.windows.net. The packet drops to the host SDN. An encapsulation layer adds a routable DIP (data center IP) address and some metadata. The packet travels the backbone network to the storage frontend. It is decapsulated and presented to the destination.

Demo

Creates a storage account. In networking, he has a choice of Public endpoint (all networks), public endpoint (selected networks), private endpoint.

He creates a private endpoint and selects the VNet/subnet. He then integrates with a private Azure DNS zone. It creates a DNS record for the storage account mapping to it’s private IP address in the VNet/subnet.

Into the storage account > Private Endpoint Connection. Tries to connect to the storage account from Internet – no access. He starts up a VM in the same VNet as the storage account private endpoint. He does a nslookup of the storage account’s private DNS name and it resolves to the IP address in the VNet.

In the VM he opens storage explorer and edits a blob. He logs into another VM that is also on the VNet. Browses to the storage blob in Storage Explorer. Opens the previously edited blob and can see the edits.

This storage account is now accessible from the VNet and nowhere else.

Announcements

  • Preview in all regions
    • Storage, ADLSv2, SQL DB, SQL DQW, Customer Own Service
  • Public preview Private Link available for Cosmos DB
    • Resions: uswestcentral, usnorth, uswest

Your Own Services

You can provide or consume your own services via Private Link.

  • Create/convert your existing services into Private Link Service – one API call to convert
  • VNet-Vnet connectivity without worrying about overlapping IP space
  • No regional, teant, subscription, or RBAC restrictions
  • More

Create Private Link Service

Lots of Marketplace scenarios spanning tenants.

  • App behind Std Load Balancer
  • Link service with one button/API call.
  • Mapped to the private IP of the load balancer

Consume Private Link Service

Similar to consuming PaaS:

  • Create a private endpoint
  • Attach to identification from the service provider
  • Done!

Approval Workflow

  1. Service provider creates a service
  2. Service provider creates a private link with Std LB
  3. Service provider shares private link service ID with consumers.
  4. Consumer creates a private endpoint in subnet with the service ID
  5. There is an approval by service provider.
  6. Consumer configures DNS to map to the private endpoint

Key Capabilities

  • Alias: Masks service provider resource IDs with a globally unique readable name. Mapped on the backend. The unique name uses a hash of stuff from service provider and other attributes.
  • Visibility: How to control access to the alias/service, e.g. stop random people DOSing you. You can make a service completely private to approved customers. Or you can make a service private to all Azure customers. Or you can limit visibility to selected subscriptions.
  • Auto-Approval: For huge services, you can avoid manual approvals. You can set audiences in the auto-approval list.
  • NAT-IP: The service provider masks customer IPs using NAT IP.

NAT IP

IP allocated by service provider

Acts as a source IP for inbound packets

Keeps service provider network private

Helps ensure overlapping IPs between source and destination are acceptable

TCP Proxy v2 Support

Service provider says they want to receive the TCP headers and extract the information. This allows you to identify unique customers even though they share a NAT IP on the service provider side: ACL, filter, etc.

Simplified Network Management

  • Predictable IP for configuring your policies
  • Cleaner ACLs on both Azure and on-prem
  • Resource the traffic the way you want
  • Approval workflow based modelling. No RBAC dependency
  • More

Demo

Goes to Private Link Center. Creates a new service and names it/selects region. Chooses the Std Load Balancer in front of the service. Selects up the frontend IP and NAT IP address. Chooses the auto-approval method.  A new Private Link Service resource is created – opens it and we can see the alias – copies it.

Creates a new Private Endpoint in a different subscription. Chooses the option to connect to the Alias ID and adds request text. Selects the VNet/subnet to put the private endpoint into.

In Private Endpoint Connections, the service provider sees the request and can approve/reject it – approves it.

On the consumer side he tries to connect to the private IP address – it’s just NATing RDP to the VMs in the service provider network.

Marketplace Services

  • Create the services
  • Advertise
  • Manage

Microsoft Ignite 2019 – Building and Managing Distributed Micro-Perimeters With Azure Firewall

Speaker: Yair Tor, Principal Program Manager

Azure Firewall

Cloud native stateful firewall as a service. A first among public cloud providers.

  • Central governance of all traffic flows
    • Built in high availability and auto scale
    • Network and application traffic filtering
    • Centralized policy across VNets and subscriptions
  • Complete VNet protection
    • Filter outbound, inbound, spoke-spoke
  • Centralized logging
  • Best for Azure

Key Features

  • Application Rules
  • Fully stateful network rules
  • NAT support
  • Threat Intelligence (GA this week)
  • Monitoring
  • Support for inbound and hybrid connections
  • Network Watcher integration

Azure Firewall Updates

  • Recently released
    • Multiple public IPs GA – up ot 100
    • Availability zones now GA (99.99% SLA)
    • Threat Intelligence based filtering now GA
    • Azure HDInsight (HDI) FQDN tag GA
    • TDS (SQL) FQDN filtering in Preview
  • Sovereign Clouds
    • US Gov
    • China
  • Coming soon: tentative ETA H2 CY 2019
    • FQDN filtering for all ports and protocols
    • Native forced tunnelling support
    • IP groups in Azure Firewall rules – coming to NSG and UDR too.

Azure Firewall Manager – See Previous Post

Preview

  • Central deployment and configuration
  • Automated routing
  • Advanced security with 3rd party SECaaS

Roadmap:

  • Virtual network support – this is the legacy form of Azure Firewall that is not the new Azure vWAN Hub Azure Firewall.
  • Split routing

Public Preview

  • Extend your security edge to Azure with Secured Virtual Hubs.
  • A secured virtual hub is an azure Virtual WAN Hub with associated security and routing policies configured by Azure Firewall Manager.
  • Easily create hub-and-spoke architectures with cloud native security services for traffic governance and protection.
  • Azure Firewall now integrated with Virtual WAN Hubs.
  • Secured virtual hub can be used as a managed central network with no on-prem connectivity.
  • There is no resource called Security Virtual Hub – it’s more of a deployment/concept. If you did a JSON deployment, it would use legacy resources.

Getting Started with Secured Virtual Hubs

One method:

  1. Create your hub and spoke architecture
  2. Select security providers: Done by secured virtual hub creation or by converting a Virtual WaN hub to secure virtual hub.
  3. Create a firewall policy and associate it with your hub: applicable only if using Azure Firewall
  4. Configure route settings on your secured hub to attract traffic: Easily attract traffic to the firewall from the spoke VNets – BGP!

Demo

Network rules are always processed before application rules in Azure Firewall. Inherited policy cannot allow stuff that parent policy denies.

Central Security and Route Policy Management

  • Deploy and configure multiple Azure Firewall instances
  • DevOps optimized hierarchical Azure Firewall Policies
  • Centralized routing configuration

GA Pricing

  • Preview has 50% discount
  • Azure Firewall in secure virtual hubs will be the same price as normal Azure Firewall
  • $100 per policy for policies that are associated with multiple hubs. No cost with policies associated with single hubs.
  • Fixed fee for outbound VPN to SECaaS partners in addition to a VPN scale unit charge.