• 2 min read

Route Type 5 L3 EVPN Tutorial

Since the inception of our Data Center Fabric program in 2019 we have been focusing on EVPN-based deployments as the preferred choice for data centers of all sizes. And historically, EVPN has been associated with Layer 2 services, such as VPLS, VPWS, E-LAN. However, network engineers know it all too well that BGP can take it all, and over time EVPN grew to support inter-subnet routing, and subsequently, layer 3 VPNs.

Now you can deploy L3 VPN services with EVPN, both in and outside of the data center. Yes, a single control plane EVPN umbrella can cover all your needs, or at least most of them.

It was important for us to start with L2 EVPN basics and cover the EVPN origins first, but now more and more workloads ditching the arcane requirement to have layer 2 connectivity, and more and more data centers can be built with pure layer 3 services.

But Layer 3 EVPN services have many flavors... Some, such as RT5-only EVPN, are quite simple, while others offer more advanced features and require symmetric IRBs, SBDs, Interfacefull mode of operation, and ESI support. To ease in the L3 EVPN introduction we chose to start with the simplest form of L3 EVPN - RT5-only EVPN.

To introduce you to the concept of L3 EVPN we prepared a comprehensive tutorial - RT5-only L3 EVPN Tutorial - that covers gets you through a fun lab exercise where you will configure a small but representative multitenant L3 EVPN network:

You'll get exposed to many interesting concepts, such as:

  • eBGP Unnumbered underlay to support the overlay services
  • iBGP overlay with EVPN address family
  • RT5-only EVPN service configuration for L3 workloads
  • EVPN service with BGP PE-CE routing protocol to support clients with routing on the host

So, have your favorite drink ready, and let's have our first dive into the world of L3 EVPN!

Pure L3 EVPN fabrics in the wild?

We shout out to the community to share their experiences with pure L3 EVPN fabrics. Have you deployed one? What were the challenges? What were the benefits?

Here is a linkedin post with some pretty interesting comments on the topic by Pavel Lunin from Scaleway.

  • 1 min read

SR Linux labs in GitHub Codespaces

The best labs are the labs that you can run anywhere, anytime, with a single click and preferrably for free.

The public SR Linux container image made labs easy to run on any machine with Docker. How about we also rule out the requirement to have a machine? Let us introduce you to GitHub Codespaces.

  • 1 min read

How SR Linux Lets You Take Control Of Your Data Center

Packet Pushers

On today’s Tech Bytes, we explore SR Linux, the network operating system developed by today’s sponsor Nokia. Why should you care about the network OS running in your data center? Nokia designed SR Linux to support automation, orchestration, and customization. We’ll dig into SR Linux’s support for YANG and gNMI and how that ties into northbound orchestration platforms, how SR Linux provides streaming telemetry, and Nokia’s development kit that lets you customize this Linux-based network OS.

Our guest is Igor Giangrossi, Sr. Director, Consulting Engineering at Nokia

Participants: Igor Giangrossi

  • 1 min read

Filtering fields in the SR Linux CLI

CLI is still king when you start managing the network's and perform all those day2+ operations.

Network troubleshooting, in particular, is one of the tasks where having a performant, intuitive, and flexible CLI is a game changer.

In this video, we explore SR Linux's CLI feature that allows you to filter the fields and order them the way the operator needs.

CLI is dead
Long live CLI

  • 13 min read

VLANs on SR Linux and Arista/Cisco

In the recent VLANs on SR Linux blog post we dived deep into the world of VLANs on SR Linux where we saw that VLAN handling in SR Linux is not quite like what we used to see on Cisco/Arista systems.

As a sequel to the original post we decided to mix SR Linux with another popular Network OS - Arista EOS. By mixing different vendor implementations we wanted to provide clear guidance on how to interop between distinct VLAN implementations and help new SR Linux to map existing VLAN concepts to the SR Linux model.

distracted-vlan

  • 16 min read

VLANs on SR Linux

Discussions: ·

What was one of the most common questions in our SR Linux discord in 2023?

EVPN? YANG? Streaming Telemetry? Programmability? Scaling DC workloads?

No. VLANs 😅

This buddy hurt you good in your early days, right? With global VLANs, trunks, and forgotten add? Your understanding of VLANs provisioning might get clouded by the industry-standard way of doing things, which may result in a lot of confusion when you start working with SR Linux.

Get yourself comfy, we are about to have a deep dive into VLANs on SR Linux.

cisco-man

  • 10 min read

SSH Terrapin Attack and Network Operating Systems

Discussions: ·

Terrapin is a prefix truncation attack targeting the SSH protocol. More precisely, Terrapin breaks the integrity of SSH's secure channel.

Pretty scary stuff, innit? Any Network Engineer/Admin understands the importance of SSH in their daily work. It's the most common way to access network devices, and it's the most secure way to do so. Is it now?

On December 18th 2023, a group of researchers from the Ruhr University Bochum publicly disclosed a new attack (CVE-2023-48795: General Protocol Flaw) on SSH protocol, called Terrapin. Targeting the very best SSH Binary Packet Protocol researchers proved that an attacker can remove an arbitrary amount of messages sent by the client or server at the beginning of the secure channel without the client or server noticing it.

But what does it mean to us, Network Engineers? Do we need to rush the vendors patching the SSH servers in their NOSes? Let's figure it out.

  • 1 min read

Show Commands

Show commands are the bread and butter of any network engineer. They are used to view the current configuration and state of the network element and are often a key tool used in troubleshooting.

Naturally, there are many show commands available on the SR Linux platform ranging from the basic commands to display environmental information to more advanced commands to display the state of the network element and its protocols. And since the SR Linux is a relatively new Network OS we wanted to make sure you can easily find the show commands you need by providing a growing list most useful show commands cataloged by topic.

Please welcome the new SR Linux Show Commands page that gets you on the fast track to finding the show commands you need.

  • 2 min read

Sharing SR Linux Terminal with SSHX

Countless times I've been in a situation where I needed to share my terminal with someone or being asked to connect to someone's device instead.

Either I exhausted my networking foo and needed help from a colleague, or I was the one who was asked to help. In both cases, the problem was the same - how to quickly, securely1 and effortlessly share the terminal with someone else.

The problem is not new and there are many options on the table. From installing a VPN software and sharing the credentials, through zero-trust solutions like teleport, to using a simple SSH tunnel. All of these solutions are great, but they require some setup and configuration. And sometimes you just want to share your terminal with someone without going through the hassle of setting up a VPN or a zero-trust solution.

The sshx.io open-source service that just popped out offers a simple solution to this problem.

  1. Install the multi-arch lightweight2 sshx binary on your machine
  2. Run sshx
  3. Share the URL with someone
  4. Enjoy collaborative terminal in a responsive web UI with a multi panel canvas

I felt an immediate urge to try it out with SR Linux. And it worked like a charm!