ExpressRoute Global Reach under the covers

After some questions in my previous blog post CLI-based analysis of an ExpressRoute private peering I decided to write an addition that includes what Expressroute Global Reach looks like for the CLI lover. In essence, Global Reach allows to use Microsoft’s backbone network for onprem-to-onprem communication. But how does it do it exactly? I have … Continue reading ExpressRoute Global Reach under the covers

Multi-region design with Azure Route Server without an overlay

Some time ago I posted a blog commenting on a possible design for interconnecting multiple Azure regions by means of Network Virtual Appliances (NVAs) and the Azure Route Server (ARS), where I used an overlay tunnel between the NVAs with VXLAN as encap protocol. I have received multiple questions to whether it would be possible … Continue reading Multi-region design with Azure Route Server without an overlay

CLI-based analysis of an ExpressRoute private peering

Quite frequently I see Azure connectivity diagrams that do not reflect accurately the topology of Azure Virtual Networks connnected to on-premises data centers via ExpressRoute. Additionally, I got the question last week of how to do some basic BGP troubleshooting in the involved networking devices in a way which is understandable by network administrators (read … Continue reading CLI-based analysis of an ExpressRoute private peering

Sending Internet Traffic from P2S Clients Through an NVA

Note: although technically working, the solution described in this article is not supported by Microsoft. Azure can be used to offer Point-To-Site (P2S) connectivity for individual users, that by leveraging a VPN client on their systems (Windows, Linux or Mac) can get connectivity to Azure resources. This P2S connectivity is often limited to Azure resources, … Continue reading Sending Internet Traffic from P2S Clients Through an NVA

Azure Route Server and NVAs running on Scale Sets

There are a couple of ways in which you can deploy NVAs in Azure, from a redundancy perspective: 1+1 (active/passive): least scalable solution, your maximum throughput will be equivalent of the one of the active NVA, while you normally have to pay for 2 VMs and 2 NVA licenses 1+1 (active/active): 2 NVAs forwarding traffic … Continue reading Azure Route Server and NVAs running on Scale Sets

Listen to the Whispers of BGP

An old Cherokee proverb says: “Listen to the whispers and you won’t have to hear the screams”. Routing problems are hard: Hard to uncover, because sometimes they will not become apparent until something happens. For example, when your backup routes disappear, and you only notice when the primary routes are gone too. And hard in … Continue reading Listen to the Whispers of BGP

Using Route Server to firewall onprem traffic with an NVA

In a previous blog we had a setup with a Network Virtual Appliance (NVA) for Internet egress and hybrid connectivity based on Azure Virtual Network Gateways. There is another fairly typical use case with regards to traffic between on-premises an Azure: firewalling it with an NVA: In some situations customers will combine the role of … Continue reading Using Route Server to firewall onprem traffic with an NVA

Azure as Internet breakout from on-premises with Route Server

This is not a topology I would define as “best practice”, or one that I see in every Azure deployment out there, but I would certainly not describe it as exotic either. In this design, organizations want to leverage Azure as Internet breakout for their on-premises systems. Potentially because they do not have a good … Continue reading Azure as Internet breakout from on-premises with Route Server

Route Server Multi-Region Design

In my previous blog I wrote my view on the characteristics of the new Azure Route Server that I am most excited about. In this one I would like to give you a glimpse of how it works with a design that I see in many organizations: a multi-region setup, with Network Virtual Appliances acting … Continue reading Route Server Multi-Region Design

Azure Route Server: super powers for your Network Virtual Appliance

Amongst the many Ignite announcements this year, my favourite is the new Azure Route Server, in public preview now, since it has the potential to dramatically change how networks are built in Azure. If you are thinking “here he comes with his BGP thing again”… You are right! Let me explain: In public cloud there … Continue reading Azure Route Server: super powers for your Network Virtual Appliance