Scaling Distributed Systems Is Hard
Stumbled upon a hilarious description of challenges encountered when trying to scale distributed systems (cluster of controllers running centralized control plane comes to mind).
It starts with “If someone tells you that scaling out a distributed system is easy they are either lying or drunk, and possibly both,” and gets better and better. Enjoy!
Monitoring leaf and spine fabric performance
A leaf and spine fabric is challenging to monitor. The fabric spreads traffic across all the switches and links in order to maximize bandwidth. Unlike traditional hierarchical network designs, where a small number of links can be monitored to provide visibility, a leaf and spine network has no special links or switches where running CLI commands or attaching a probe would provide visibility. Even if it were possible to attach probes, the effective bandwidth of a leaf and spine network can be as high as a Petabit/second, well beyond the capabilities of current generation monitoring tools.
The 2 minute video provides an overview of some of the performance challenges with leaf and spine fabrics and demonstrates Fabric View - a monitoring solution that leverages industry standard sFlow instrumentation in commodity data center switches to provide real-time visibility into fabric performance. Fabric View is an application running on InMon's Switch Fabric Accelerator SDN controller. Other applications can automatically respond to problems and apply controls to protect against DDoS attacks, reduce latency and increase throughput.
Visit sFlow.com to learn more, evaluate pre-release versions of these products, or discuss requirements.
Alteon’s REST API
AlteonOS has a reach REST API for monitor, operation, and configuration.REST can be used/called with verity of programming languages, or even just using wget. However, since this blog was already using TCL for AppShape++ scripting, we may as well keep using TCL for REST too. However, RESTing with TCL is a bit pain in the ..., so this time I'll use python instead.
All most forgot to explain what REST is. Its a way to run remote procedures calls using HTTP. Example calls:
- Read interface counters
- Update real's weight
- Bring down a real inside a group
Here are two screenshots. The first is how I get the current status of real 1, and the second is how I disable real 1.
Lab goal
Using the base setup, create python script to toggle the status of real 1 from not enabled to enabled and from disable to enable.
Setup
The loadbalancer is Radware's Alteon VA version 29.5.1.0
The initial Alteon VA configuration can Continue reading
Friday News Analysis: Lightweight Junos for Cloud Builders on an Open Switch
Finally! An Open Switch With a Reliable Operating System (Juniper) Today, Juniper Networks announced a fundamental transformation in the networking industry. Until now, disaggregated networking software and hardware has been in the domain of only those customers who had a large amount of resources to take “unproven software,” combined with original design manufacturer […]Friday News Analysis: Rumors Around Juniper’s Security Products
Juniper whips out knife, slices off security products Note that this is not official Juniper news from what I can tell. The report comes from the tech equivalent of a gossip rag. Maybe I shouldn’t bring it up. But…it seems all too plausible. Here are several bits from the article I stitched into […]Friday News Analysis: Cisco on Network Services Headers
Network Services Headers (NSH): Creating a Service Plane for Cloud Networks (Cisco) Cisco has developed Network Services Headers (NSH), a new service chaining protocol that is rapidly gaining acceptance in the industry. Based on lessons learned in earlier versions of vPath, and realizing that NSH would only succeed with broad acceptance from a […]PlexxiPulse—Facebook’s New Network
The internet has been buzzing about Facebook’s redesigned datacenter architecture. Facebook, which is used by more than 1.35 billion people, recently restructured their infrastructure to increase flexibility and agility to rapidly adjust to application requirements. Our own Marten Terpstra shared his take on the redesigned infrastructure this week on the Plexxi blog—it’s definitely worth a read. Below we share some of the articles that covered Facebook’s new datacenter architecture, as well as other happenings in the networking space this week.
In this week’s PlexxiTube of the week, Dan Backman explains how much fiber is required to connect datacenters using Plexxi’s datacenter transport fabric solution.
Gigaom: Facebook Redesigned the Data Center Network: 3 Reasons It Matters
By Derrick Harris
Earlier this month, Facebook announced a new data center networking architecture that it calls, fittingly, “data center fabric.” The company explained the design and the rationale in an engineering blog post, and Gigaom’s Jonathan Vanian covered the news, but it’s a big enough deal that we had Facebook Director of Network Engineering Najam Ahmad on the Structure Show podcast this week to talk about the new fabric in more detail.
CIO: How (and Why) Facebook Excels at Data Center Continue reading
Friday News Analysis: D-Link for Business Adds New Wireless Controller
D-Link Expands its Unified Wireless Portfolio with New Wireless Controller Supporting up to 256 Access Points D-Link today announced the Unified Wireless Controller (DWC-2000), a new centralized Wireless LAN manager designed specifically for education, hospitality and medium-to-large enterprises. The DWC-2000 can support up to 256 access points per controller, and up to 1,024 […]Imposing Artificial Limitations to Develop Skills
I'm a big fan of imposing artificial limitations on yourself in order to aid skill development. Here are some quick ideas:- When troubleshooting network devices from the CLI, try not to look at the configuration. Use only "show" or "debug" commands instead. I found this enormously beneficial when practicing for CCIE.
- When troubleshooting larger operational issues or learning a new environment, try not to log into individual devices at all. Force yourself to use only your network management system, NetFlow, packet captures, or host-based tools like ping, traceroute, or nmap.
- When learning automation or orchestration skills, force yourself to write scripts, run API calls, or use your favorite orchestration tool to do simple things, even if it doesn't seem like they merit the extra effort.
Imposing Artificial Limitations to Develop Skills
I'm a big fan of imposing artificial limitations on yourself in order to aid skill development. Here are some quick ideas:- When troubleshooting network devices from the CLI, try not to look at the configuration. Use only "show" or "debug" commands instead. I found this enormously beneficial when practicing for CCIE.
- When troubleshooting larger operational issues or learning a new environment, try not to log into individual devices at all. Force yourself to use only your network management system, NetFlow, packet captures, or host-based tools like ping, traceroute, or nmap.
- When learning automation or orchestration skills, force yourself to write scripts, run API calls, or use your favorite orchestration tool to do simple things, even if it doesn't seem like they merit the extra effort.
iPexpert’s Newest “CCIE Wall of Fame” Additions 12/05/2014
Please Join us in congratulating the following iPexpert clients who have passed their CCIE lab!
- Mathew Varghese, CCIE #45557 (Collaboration)
- Nick Thompson , CCIE #45731 (Collaboration)
We Want to Hear From You!
Have you passed your CCIE lab exam and used any of iPexpert’s or Proctor Labs self-study products, or attended a CCIE Bootcamp? If so, we’d like to add you to our CCIE Wall of Fame!
Hotel California Effects of Public Clouds
In his The Case for Hybrids blog post Mat Mathews described the Hotel California effect of public clouds as: “One of the most oft mentioned issues with public cloud is the difficulty in getting out.” Once you start relying on cloud provider APIs to provide DNS, load balancing, CDN, content hosting, security groups, and a plethora of other services, it’s impossible to get out.
Interestingly, the side effects of public cloud deployments extend into the realm of application programming, as I was surprised to find out during one of my Expert Express engagements.
Read more ...The Attributes of a Great Network Device API
What makes a good API? A device providing an API is only the start of the story; if its unusable, or unreliable its useless. This post is a response to one of a couple of points I made about Kirk Byers’ recent post on Arista’s API and the comments that followed. Much respect to (and admiration for) Arista […]
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The post The Attributes of a Great Network Device API appeared first on Packet Pushers Podcast and was written by Steven Iveson.
Guests Needed for Design + Build 2015 Podcasts
Updated 12-January-2015 to include survey form. I’m working on a series of “design and build” podcasts in 2015 for Packet Pushers. The idea is to take a network protocol, project, business challenge, reference architecture, etc. and talk through the why and how. Are you willing to be a guest to share your real-world experience? I’d […]
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The post Guests Needed for Design + Build 2015 Podcasts appeared first on Packet Pushers Podcast and was written by Ethan Banks.
Ansible Chicago Meetup Recap
If you don't follow Ansible's VP of Community, Greg DeKoenigsberg, on Twitter you may have missed his recap of the Ansible Chicago Meetup.
Dean Strelau and Rick Pollak of Trunk Club invited us to host our inaugural Ansible Chicago meetup at their headquarters in downtown Chicago. This is often how it happens: a company that uses Ansible volunteers to host a meetup, and gets the benefit of being seen as a technology leader in their community; we get to show the local community how a prominent user puts Ansible to best use. Everybody wins! We’ve done similar meetups in New York, San Francisco, London, and many other cities.
Trunk Club, though, was one of the most fascinating yet. For those who aren’t familiar with the business model,check out their site for a detailed description. The short version: they talk to you about what you like, they use business intelligence to help their stylists pick out the best clothes for you, and then they send you a trunk full of clothes they think you’ll like. And then you keep what you like, send back what you don’t, and they charge you appropriately. Great model, Continue reading
Using Cisco VIRL for CCIE Preparation
Click here to download the INE VIRL topology and initial configs
After long anticipation, Cisco’s Virtual Internet Routing Lab (VIRL) is now publicly available. VIRL is a network design and simulation environment that includes a GNS3-like frontend GUI to visually build network topologies, and an OpenStack based backend which includes IOSv, IOS XRv, NX-OSv, & CSR1000v software images that run on the built-in hypervisor. In this post I’m going to outline how you can use VIRL to prepare for the CCIE Routing & Switching Version 5.0 Lab Exam in conjunction with INE’s CCIE RSv5 Advanced Technologies Labs.
The first step of course is to get a copy of VIRL. VIRL is currently available for purchase from virl.cisco.com in two forms, a “Personal Edition” for a $200 annual license, and an “Academic Version” for an $80 annual license. Functionally these two versions are the same. Next is to install VIRL on a hypervisor of your choosing, such as VMWare ESXi, Fusion, or Player. Make sure to follow the installation guides in the VIRL documentation, because the install is not a very straightforward process. When installing it on VMWare Player I ran into a problem with the NTPd Continue reading
Automating SAN Zoning with Schprokits
I’m always on the lookout for ways to simplify the configuration of integrated systems through automation. I also currently work for a systems integrator, and I take any opportunity I can get to automate a process, a la “assembly line”, creating a consistent, predictable outcome.
One particular task that both integrators and customers alike are having to do manually is the act of Fibre Channel Zoning. For those that aren’t familiar, Fibre Channel doesn’t work in the same way that Ethernet does (i.e. Flood and Learn). In order to get two nodes to communicate over a SAN fabric, a configuration must be put into place to allow them to talk – roughly equivalent to a Layer 2 ACL. Each server’s HBA must be given permission to access a storage target on the fabric, which means that any time compute power is added or removed, this configuration needs to be revisited. This is a prime candidate for automation.
This article will show how I am using Schprokits to simplify zoning configuration. I am tightly adhering to the idea that this kind of information should be pulled directly from live infrastructure (in this example, I’m using Cisco UCS), not a (usually) stagnant spreadsheet, or Continue reading
Show 215 – SDN Training & Certifications with Wendell Odom
Software defined networking (SDN) has arrived in the form of vendor released products. If you follow this show, you know that these products are largely incompatible. Certainly there’s no “one size fits all” when it comes to SDN technologies today. In SDN’s awkward tween years, what are network engineers trying to stay current to do? […]
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The post Show 215 – SDN Training & Certifications with Wendell Odom appeared first on Packet Pushers Podcast and was written by Ethan Banks.