Netflix Releases bpftop: An eBPF-Based Application Monitor

Extended Berkeley Packet Filter, eBPF to its friends, enables you to run sandboxed programs in a privileged context in the Linux kernel. Netflix has unveiled bpftop, a new open source command-line tool designed to enhance the performance optimization and monitoring of eBPF applications. As the streaming giant continues integrating eBPF technology into its infrastructure, ensuring these applications operate efficiently has become a top priority.

VXLAN Virtual Labs Have Never Been Easier

I stumbled upon an “I want to dive deep into VXLAN and plan to build a virtual lab” discussion on LinkedIn1. Of course, I suggested using netlab. After all, you have to build an IP core and VLAN access networks and connect a few clients to those access networks before you can start playing with VXLAN, and those things tend to be excruciatingly dull.

Now imagine you decide to use netlab. Out of the box, you get topology management, lab orchestration, IPAM, routing protocol design (OSPF, BGP, and IS-IS), and device configurations, including IP routing and VLANs.

Human Generated Questions About AI Assistants

I’ve taken a number of briefings in the last few months that all mention how companies are starting to get into AI by building an AI virtual assistant. In theory this is the easiest entry point into the technology. Your network already has a ton of information about usage patterns and trouble spots. Network operations and engineering teams have learned over the years to read that information and provide analysis and feedback.

If marketing is to be believed, no one in the modern world has time to learn how to read all that data. Instead, AI provides a natural language way to ask simple questions and have the system provide the data back to you with proper context. It will highlight areas of concern and help you grasp what’s going on. Only you don’t need to get a CCNA to get there. Or, more likely, it’s more useful for someone on the executive team to ask questions and get answers without the need to talk to the network team.

I have some questions that I always like to ask when companies start telling me about their new AI assistant that help me understand how it’s being built.

Question 1: Laying Continue reading

Ansible Set Operations Do Not Preserve List Order

Here’s another Ansible quirk, this time caused by Python set behavior.

When I created the initial device configuration deployment playbook in netlab, I wanted to:

  • Be able to specify a list of modules to provision.1
  • Provision just the modules used in the topology and specified in the list of modules.

This allows you to use netlab initial to deploy all configuration modules used in a lab topology or netlab initial -m ospf to deploy just OSPF while surviving netlab initial -m foo (which would do nothing).

Bridging Packet Walk In VXLAN/EVPN Network

In this post I walk you through all the steps and packets involved in two hosts communicating over a L2 VNI in a VXLAN/EVPN network. The topology below is the one we will be using:

The lab has the following characteristics:

  • OSPF in the underlay.
  • Ingress replication for BUM traffic through the use of EVPN.
  • ARP suppression is enabled.
  • ARP cache is cleared on Server-1 and Server-4 before initating the packet capture.
  • Server-1 is the host sourcing traffic by pinging Server-4.

Server-1 clears the ARP entry for Server-4 and initiates the ping:

sudo ip neighbor del 198.51.100.44 dev ens160
ping 198.51.100.44
PING 198.51.100.44 (198.51.100.44) 56(84) bytes of data.
64 bytes from 198.51.100.44: icmp_seq=1 ttl=64 time=6.38 ms
64 bytes from 198.51.100.44: icmp_seq=2 ttl=64 time=4.56 ms
64 bytes from 198.51.100.44: icmp_seq=3 ttl=64 time=4.60 ms

Below is packet capture showing the ARP request from Server-1:

Frame 7854: 60 bytes on wire (480 bits), 60 bytes captured (480 bits) on interface ens257, id 4
Ethernet II, Src: 00:50:56:ad:85:06, Dst: ff:ff:ff:ff:ff:ff
Address Resolution Protocol (request)
    Hardware type: Ethernet (1)
    Protocol type:  Continue reading

DNS and Truncation in UDP

I’ll press on with another item within an overall theme of some current work in DNS behaviours with a report of a recent measurement on the level of compliance of DNS resolvers with one aspect of standard-defined DNS behaviour: truncation of DNS over UDP responses.

DNS and Truncation in UDP

I’ll press on with another item within an overall theme of some current work in DNS behaviours with a report of a recent measurement on the level of compliance of DNS resolvers with one aspect of standard-defined DNS behaviour: truncation of DNS over UDP responses.

Boat build phase – part2

You can only live for so long on laughing cow, pot noodles, soup and beans on toast, the boat diet is good for losing weight but not for your wellbeing. I got lucky with the weather as winter was pretty mild up until late October but when it turned you certainly did feel the cold on the boat. You would have to be crazy to try and survive on a boat in winter without a stove or some form of heating.

SuzieQ Network Observability

SuzieQ Network Observability

In today’s post, we’re exploring SuzieQ, an open-source network observability platform that’s making waves in the way we monitor and understand our networks. It supports a wide array of devices from top vendors like Arista, Cisco, and Juniper, among others. We’ll start with the fundamentals and finish with a practical example to clearly illustrate how SuzieQ sets itself apart from other automation tools.

What We Will Cover?

  1. What exactly is SuzieQ?
  2. How does SuzieQ work?
  3. How to install SuzieQ?
  4. SuzieQ terminology (Configuration, Inventory, suzieq-cli, poller)
  5. Configuration and Inventory files
  6. Examples using OSPF Topology
  7. Path Analysis

What Exactly is SuzieQ?

I first came across SuzieQ a while back but didn't dive deep into it because tools like Netmiko or Napalm were fitting my needs just fine. That changed when I tuned into a recent Packet Pushers podcast featuring Dinesh Dutt, the brain behind SuzieQ. Hearing him talk about it got me really interested.

After the podcast, I couldn't hold back from giving SuzieQ a try. There have been many times when I found myself writing custom scripts to get things done, only to discover that SuzieQ could have handled those tasks much more smoothly.

So, what is SuzieQ? In simple Continue reading