SWITCH Stories
Cisco service predicts SD-WAN problems
Published on: 2022-06-14
Cisco is set to offer the first fruits of its technology that promises to let enterprises proactively avoid network problems and increase application performance. At its Cisco Live event this week the company took the wraps off ThousandEyes WAN Insights service that will let Cisco SD-WAN...
MPLS, SDN, even SD-WAN can give you the network observability you need
Published on: 2022-04-25
What do router networks and a preschool have in common? A lot more than you think. Read on for the answer. To the average enterprise, “network” means “router network”. It’s not that there aren’t other things in the network, but that the whole of enterprise networking is about building IP...
Tech Bytes: Nokia Fabric Services System Streamlines Network Automation For Application Stacks (Sponsored)
Published on: 2022-07-25
Today on the Tech Bytes podcast we welcome back sponsor Nokia to talk about a compelling feature in Nokia’s Fabric Services System. This feature, called Connect, lets Fabric Services System integrate with platforms such as VMware, OpenStack, and Kubernetes to streamline the provisioning of...
Network Break 391: IT Spending To Rise; Rating Your Emotional Response To Vendor Products
Published on: 2022-07-25
Take a Network Break! This week we cover new DLP capabilities from Cato Networks, updates to the open-source Cilium project for your eBPF and service mesh needs, and why Cisco is streamlining how partners can offer Webex as a managed service. NVIDIA announces a platform for hybrid quantum and...
Twilight Zone: File Transfer Causes Link Drop
Published on: 2022-07-13
Long long time ago, we built a multi-protocol WAN network for a large organization. Everything worked great, until we got the weirdest bug report I’ve seen thus far: Try to figure out what was going on before reading any further ;) I got onsite, the customer started the file transfer, and (as...
How to Launch an Effective Zero Trust Initiative
Published on: 2022-07-07
We define Zero Trust as a strategic approach to cybersecurity that secures an organization by eliminating implicit trust and continuously validating every stage of a digital interaction. Boiled down, Zero Trust simplifies risk management to a single use case: the removal of all implicit trust...
Modifying Maximum Throughput of Catalyst8000v
Published on: 2022-07-05
The Catalyst8000v is Cisco’s virtual version of the Catalyst 8000 platform. It is the go to platform and a replacement of previous products such as CSR1000v, vEdge cloud, and ISRV. When installing a Catalyst8000v, it comes with a builtin shaper setting the maximum throughput to 10 Mbit/s as can...
Repost: Buffers, Congestion, Jitter, and Shapers
Published on: 2022-06-27
Béla Várkonyi left a great comment on a blog post discussing (among other things) whether we need large buffers on spine switches. I don’t know how many people read the comments; this one is too valuable to be lost somewhere below the fold You might want to add another consideration. If you have...
Who Owns Security ACLs?
Published on: 2022-06-17
A previous blog, Do You Know Your Flows? discussed figuring out what flows are in your network (network edge, etc.). And the time challenges that can present. It also lightly touched on what I think should be access list (“ACL”) best practices (but usually are not). And on some of the issues...
Cut-Through Switching Isn’t A Thing Anymore
Published on: 2021-04-15
So, cut-through switching isn’t a thing anymore. It hasn’t been for a while really, though in the age of VXLAN, it’s really not a thing. And of course with all things IT, there are exceptions. But by and large, Cut-through switching just isn’t a thing. And it doesn’t matter. Cut-through versus...
Switching Tracks – Saying Goodbye to VMware
Published on: 2022-05-24
After almost 6 years with VMware (1 month short!), it’s with a bittersweet feeling that I’m saying goodbye to my extended family this week. It’s been said before and I’ll say it again: the connections and friends I made at VMware, will last a lifetime. I was first drawn to VMware by NSX. When I...
Introducing MuteDeck for Zoom (and..)
Published on: 2022-05-17
After months of hard work and incorporating tons of feedback, I’m very happy to introduce the future of the Stream Deck plugin for Zoom; MuteDeck. As you might know, the Stream Deck plugin for Zoom is an easy way to control a Zoom meeting via the Stream Deck. Knowing whether you’re on mute and...
Cisco Cat9300X – Tech Field Day
Published on: 2022-04-14
The other week I had the privilege of participating in Tech Field Day Exclusive with Cisco 2022. One of the presentations that I enjoyed was the talk on the C9300X. I think this is because I am currently working heavily with them on a current project As I said, the Cisco Catalyst 9300 is a...
ZPE - A New Swiss Army Knife Networking Product
Published on: 2021-09-27
ZPE presented at Networking Field Day 26 on Sept 16, 2021 and I will be honest, at first I couldn't figure out where to put ZPE in terms of a product and service category. As they were a first time NFD presenter and I had not heard of them before I was asking myself, are they a remote console...
Why Haven’t I Tried ZeroTier Before?
Published on: 2022-01-28
I have a confession to make: I am not currently using ZeroTier. It turns out that in this respect I am in a minority among my peers at Networking Field Day 27 and after listening to a great introduction to ZeroTier by company founder and original software author Adam Ierymenko, I now know that I...
EX3400 Disk Space and Upgrades
Published on: 2021-12-21
The Juniper EX3400 switch series is a decent access switch. But a Product Manager chose to save $0.50 on COGS by choosing a 2GB disk. That’s just not enough space to handle normal Junos upgrades. This has wasted untold engineer hours on busywork. I hope that person (A) got a bonus, and (B) is...
802.1X Deployment Guide: Interface configuration
Published on: 2021-10-18
In a previous post, I explained how to configure dot1x in a switch global configuration. In this article, I’ll explain the best practice about dot1x interface configurations. If you do not know what are the benefits that dot1x framework gives, I suggest you to read this article. First of all,...
VNC Cannot Currently Show the Desktop
Published on: 2021-03-17
I have a Dell Latitude E5440 laptop which most of the time I run headless in a 3D-printed stand next to its slightly bigger brother, a Dell E6500 or similar. The laptops don’t take up much space on my desk in this vertical configuration (which is helpful as I have four laptops on my desk) and I...
Zodiac FX Gets a 3D Printed Case
Published on: 2021-02-18
Not content with having dug the Northbound Networks Zodiac FX out of a pile of overlooked technology in my office, I thought that the poor thing desperately needed to have a case to sit in. When I originally received the switch, I did not have a 3D printer and had no idea what it would take to...
Introducing DNS Hammer, Part 2: Auditing a Name Server’s Rate Limiting Configuration
Published on: 2021-01-25
Part one of the series discusses DNS reflection attacks and DNS rate limiting. This post shows how to use DNS Hammer to audit a DNS server’s rate limit configuration. A dedicated web site https://www.dnshammer.com offers the tool for download and instructions how to use it. This blog posts shows...
What CCDEv3 Means to You and Me
Published on: 2021-01-15
Cisco's CCDE Version 3 announcement brings about significant changes to our favorite certification program. As the year progresses I will write articles about the specific changes and how candidates can prepare for the new version of the exam. For now, I would like to cover what moving to the...
Cable testing on Juniper EX switches
Published on: 2020-09-22
Does anyone use the cable test feature on EX switches? Did you even know you could do this kind of thing? In case you didn’t, here is a bit of background and an example. The Time Domain Reflectometer (TDR) test has been available on the EX switches for some time, but not a lot of […]
fpc1 vlan-id(32768) to bd-id mapping doesn’t exist in itable
Published on: 2020-09-21
If you are getting this message appearing repeatedly on a Juniper switch (e.g. an EX4300), check you don’t have an IRB interface that is not attached to a VLAN. Alternatively, check your IRBs all have IP addresses.
Analyzing a failed TLS connection
Published on: 2020-07-13
This post demonstrates how to correlate two or more trace files to analyze a broken connection. We identify the root cause and gather information about the network topology. Tracefiles are available at http://www.packet-foo.com/blog/TLS/Skype.zip We assume that the reader is familiar with TCP...
Developing on iPad
Published on: 2020-05-18
The way we have created content has changed immensely over the past years. When the iPad first came out I was a little skeptical as it really was just a large iPhone and had minimal functionality for content creation. Content consumption on the other hand was always something that the iPad did...
Physically man-in-the-middling an IoT device with Linux Bridge
Published on: 2019-12-14
This is a quick writeup of how I did some analysis of an IoT device (The Thing) by physically inserting a Linux box into the network path between The Thing and the network service it consumed. The approach described here involves being physically close to the target system, but it should work...
Arrcus: An Application of Modern OEM Principles for Whitebox Switches
Published on: 2019-10-08
What’s a pirate’s favorite switching platform? Arr-cus. 😂 And before I make a joke about networking ship-sets (too late), I’ll move onto what Arrcus is and why you should be checking them out! Arrcus manufactures white box switches running ArcOS, their latest generation of switches leveraging...
GORUCK D-Day Tough - AAR
Published on: 2019-09-24
rd Tough. My two oldest kids and I drove over Saturday evening and parked close to the start point. We were slated to start at 10PM so were happy to be in place around 9 so get changed and geared up. This event was something we were looking forward to for multiple reasons. First, GORUCK events...
Cisco Live 2019 – A Whirlwind of Networking Goodness
Published on: 2019-06-24
Cisco Live 2019 came and went in a whirlwind of fantastic meetups, excellent sessions, and genuinely nerdy networking conversations. Cisco Live session content was top notch. Jasper Bongertz’s Wireshark talk blew the audience away with useful packet capture and troubleshooting tips, and Denise...
CCDE Thoughts After Cisco Live 2019
Published on: 2019-06-18
My CCDE Thoughts After Cisco Live 2019The CCDE exam was conspicuously absent from the grand re-imagining of the CCNA/CCNP/CCIE certification programs. Here's a brief summary of the announcements (everything takes effect on February 24, 2020):CCIE Routing & Switching is being renamed to CCIE...
Arista's Programmability Strategy
Published on: 2017-10-01
Arista is largely known for its operating system, best known as EOS. Arista has been known to deploy new features at a more rapid pace than other vendors and to have a more open OS–since EOS was the first production-grade network network operating system to expose any form of Linux to end users....
Three Months with Google Fiber
Published on: 2017-01-06
I'm one of the lucky few to benefit from Google Fiber's recent expansion into new regions (before they nixed the whole thing). I've had the service fire three months now and figured I should write up my experience with it thus far. Google Fiber announced that it would be expanding to the...
Configuring Macvlan and Ipvlan Linux Networking
Published on: 2016-03-28
Macvlan and Ipvlan are both Linux type networking interfaces that are both supported by the Linux kernel. They are unique for a few different reasons. One thing that makes them both very attractive is they do not use bridges in their implementation and natively namespace aware. It solves some...
It's Dirty Work, But Somebody's Gotta Do It
Published on: 2015-02-14
Network Engineers are known to have to work in dirty places like under desks, janitors closets (err I mean network closets), and those weird spaces in mechanical rooms in which someone decided to hide a switch or two. Nothing though in networking compares with some of the jobs that this year's...