Upscale AI at NFD40: The Pitch Before the Product
About thirty seconds into Aravind Srikumar’s NFD40 talk, he said the thing that made me stop fidgeting and start paying attention: “We haven’t announced any products yet.
Networking
AI Networks Can't Use SDN. Netris Built What's Next.
Alex Saroyan had about ninety seconds onstage before he made the architectural claim that the rest of the AI-networking conversation has been ducking.
Ethernet Commoditizes Everything. Except EOS
Halfway through Tom Emmons’ scale-out segment at NFD40, a fellow delegate looked at Arista’s load-balancing slide and said what most of us were thinking… this could have any vendor’s logo on it.
One Throat to Choke, or Any Silicon You Want: Cisco at NFD40
Cisco showed up to NFD40 selling two different pitches in the same session, and nobody on stage reconciled them.
Nokia at NFD40: Networking in the AI Era
I’ve been building networks for nearly thirty years. I understand leaf-spine fabrics, BGP design, VRF isolation, ECMP, and congestion management.
Stop using 192.168.1.0/24: A Contrarian Guide to Home Network Addressing
If you’re a contractor, consultant, or anyone who VPNs into multiple client networks, you’ve experienced the pain. You connect to a Client’s VPN, and suddenly you can’t print to your local printer.
Introducing Graphiant: The Future of Network-as-a-Service
As businesses continue to shift towards remote and distributed work environments, the need for secure and reliable network infrastructure has never been greater.
IP Infusion powering the world from behind the scenes
Founded by Kunihiro Ishiguro and Yoshinari Yoshikawa the founders of GNU Zebra, came together to form IP Infusion back in 1999 as a commercial-grade, hardware-independent networking software company.
VMware NSX is something something awesome
At times I have trouble focusing on writing articles for some of the presentations I am exposed to at Tech Field Day. Because of that, I really wanted to try something different.
BGP Communities
BGP Communities has to be one of my favorite features added to the BGP protocol.
Cisco VIRL released into the wild
After much waiting from all of us, Cisco has released, on “cyber Monday” no less, VIRL.
AS-Path Filtering
Before we get into the how, let’s talk about the why.
HP talks SDN at Interop NYC 2014
I generally try to avoid oversharing when it comes to my thoughts about presentations, but I have to mention that after sitting down with Glue Networks and their “SDN” presentation, it was truly a …
Using Deny ACEs in your PBR ACL on your Nexus 7k
Quite a while ago I had a need for some network duct tape… Policy Based Routing while useful should only IMHO be used as a temporary fix.
Cisco Nexus 2000: A Love/Hate Relationship
My feelings towards the Nexus 2000 Fabric Extender (FEX) are hardly a secret. The myriad of design choices and platform limitations present engineers with some rather difficult decisions.
QinQ: IEEE 802.1Q Tunneling
In situations where service providers want to offer transparent LAN services that preserve a customers VLAN tags across your Layer-2 network, this amendment to the IEEE 802.
MDS Fibre Channel Switching Basics for Network Engineers
Recently I’ve been lucky enough to be challenged with learning a bit about Fibre Channel Switching, but I’m even luckier in that I’m getting to know it on a set of MDS switches running NX-OS …
Juniper QFabric, Junosphere, Automation, and More
The second day of Network Field Day 2 started early at the Juniper EBC, luckily Abner Germanow was prepared with breakfast for the weary and slightly hung over delegates.
Network Duct Tape Gone Wrong
As many of you may know, I’m in the middle of a huge network redesign, last week our new firewalls finally arrived and it became time for us to start migrating services onto the edge network I’ve been …
F5’s iRules — My first look
I’ve never had the opportunity to really do much with F5 load balancers in the past, but recently one our system engineers needed some load balancing setup, and wanted to know if we could assign some …
Nexus 7000 vPC Features
Next generation data centers across the world are taking advantage of Cisco’s Virtual PortChannel.
NX-OS 5.2(1) for the Nexus 7000
Rather quietly, at least I never heard anything, on July 29th, Cisco released NX-OS Version 5.2(1) for the Nexus 7000 platform.
IP SLA Basics
IP SLA is a function of Cisco’s IOS enabling you to analyze a Service Level Agreement (SLA) for an IP application or service.
IP Multicast Routing Concepts
Can you imagine a video conference taking place on a primarily T1 based WAN? Multiple copies of the same video stream being unicast from the host to each participant.
SVI Autostate
Switch Virtual Interfaces, or SVIs on Cisco IOS use a feature called autostate to determine the interface availability.
Nexus 1000v – Out of Ports on a Virtual Switch?
Yesterday, work presented an interesting issue I wanted to share with everyone.
BGP Essentials – The Art of Path Manipulation
Most enterprise networks use BGP to peer with their Internet Service Providers if they want to be multi-homed.
Introduction to the Nexus 1000V
The Nexus 1000V is a software-based Cisco NX-OS switch that integrates into VMware vSphere 4 and operates inside the VMware ESX hypervisor.
OSPF Graceful Shutdown
Striving to reach that last 9? Looking for a way to increase your uptime while still being able to do maintenance on your network? Wish you could shutdown your OSPF neighbors like your BGP peers?
IOS Embedded Packet Capture
Tired of setting up SPAN sessions? Need to do some packet analysis? Since IOS 12.4(20)T Cisco has made Embedded Packet Capture (EPC) available.
Nexus Virtual Port Channel (vPC)
The Nexus 7000 and 5000 series have taken port-channel functionality to the next level by enabling port-channels to exist between links that are connected to different devices.
Setting up a Cisco Access Server
Whether your networking lab has 3 devices or 30 an access server, also commonly called a terminal server, is the vital connection between you and those devices.
HSRP, VRRPd, and GLBP Compared
In the world of first hop redundancy, we have plenty of choices. In order to make the right decision for your network you should know the basics regarding all three.
BGP Tips! multipath load balancing
Previous thoughts on load balancing BGP were that it is not a load balancing protocol and in order to achieve any sort of balanced traffic you would have to perform some sort of route balancing.
Working with the Embedded Event Manager (EEM)
Cisco IOS has plenty of gems contained within, but few are as fun, and as endlessly useful as the Embedded Event Manager, or EEM.
More IOS Tips
Learning the particulars of Cisco IOS is one of the most valuable things a network engineer can do. These skills will be the basis of everything you do on the lab and on your network.
Using the Cisco IOS Archive Command
The Cisco IOS archive command is not only very useful in keeping configuration archives, but it can also be used to log commands entered into the router, along with their user name.
Introduction to Private VLANs
The concepts behind Private VLANs are in fact rather simple, but it is quite easy to get discombobulated in the details.
Bidirectional Forwarding Detection
Bidirectional Forwarding Detection (BFD) is a UDP-based protocol that provides fast (very fast!) routing protocol independent detection of layer-3 next hop failures.
Measuring Cable Lengths on a Catalyst Switch
A while back, I was playing on a 3750 switch in a customers lab and came across something I’ve never seen before. It seems that some Cisco switches have a built in Time-domain reflectometer, or TDR.
Using Discontiguous Wildcard Masks in ACLs
Unlike subnet masks, wildcard masks allow you to use discontiguous bits which enable you to match on a range of values.
Using Regular Expressions on Cisco IOS
As a followup to my previous post on Regular Expression Basics, I wanted to give a few examples on using them on Cisco IOS.
More BGP tricks
At times, the ‘rules of BGP’ don’t fit the needs of our productions networks. When we get into today’s production networks how often do book configurations apply? I’ll tell you one thing.
Cisco VOIP Basics – Call Broadcast for Cisco CME
This is the fourth and final part of my Cisco voip basics series. ( Parts 1, 2 & 3 ) Our goal in this series has been setting up a working voice gateway that you could use in your home office.
Connecting Dynamips to your local network (OSX)
Ever wanted direct network access to your Dynamips lab? Have you ever needed to lab something that used the SDM, but you run Dynamips under OSX?
Policy Based Routing
Policy based routing is the process of altering a packets path based on criteria other than the destination address, commonly referred to as ‘policy routing’.
Using /31 subnets for point-to-point interfaces
Recently a “colleague”, I use that term very loosely here, was reviewing my recommendations for changes on his network.
IOS ACL Resequencing
This is one of those tricks you wish you learned about 10 years ago, but never did. You know how easy it is to mess up a nice looking access list.
Cisco MPLS VRF Configuration and Demo
A while back I asked everyone to vote on what topic they wanted to see next, and by no surprise almost every voted for MPLS VRFs.
JunOS Olive Demonstration
As a follow up to my JunOS Olive tutorial, I made a demonstration video that shows Multicast functioning via OSPF to another Olive and an ImageStream VM.
Running JunOS under VMWare (updated – again!)
Interested in trying out JunOS? Can’t afford to build a real Juniper lab? Sounds like you need some Olives.
Route Selection
One of the most common questions I get concerns path selection within the router.
Cisco VOIP Basics – Cisco Dial Plans
This is the third part of my Cisco voip basics series. ( Parts 1, 2 & 4 ) Our goal is to help you configure a Cisco voice gateway that you could use in your home office.
Cisco VOIP Basics – Installing Cisco Call Manager Express
This is the second part of my Cisco voip basics series. ( Parts 1, 3 & 4 ) Our goal in this series is to setup a working voice gateway that you could use in your home office.
Testing TCP Connectivity on Cisco Devices
Ever thought you might be having some Layer 4 connectivity issues? Pings as you should know are ICMP transmissions and ICMP is a Layer 3 protocol (commonly used to send error messages).
Cisco VOIP Basics
This is the first part of my Cisco voip basics series. ( Parts 2, 3 & 4 ) VOIP is obviously becoming a large part of networks, even now part of your CCNP requirements are basic voip knowledge.
Configuring a Cisco Router as a Frame Relay Switch
One of the most effective lab setups uses frame relay as its primary transport method. This is a configuration that many people use and praise for its ease of setup and maintenance.
Setting up VOIP lab
This week I’ve started setting up a VOIP lab to explore the technology and when I’m done, I plan to integrate it into my home network.
Demystifying Cisco Config Register Bits
Ever accidentally set your config register to a random value that isn’t in the Cisco documentation? No? Neither have I, but one day I encountered someone on #cisco that had.
Cisco IOS Tips and Tricks
So, I’m sure these have been posted almost on every networking blog under the sun, but who knows, right?
Layer 2 Ethernet transport over OpenVPN
One of the things I used to deploy frequently at my previous position was transport for other ISPs and businesses.
Using OSPF to create unlicensed full duplex connections.
Recently one of my clients asked me to help resolve an issue at an aggregation point on their network.
How does latency effect throughput?
One of the questions I get asked several times a week by my clients is as such.
Cisco IOS Naming Conventions
As I started building this lab, I realized that I had to find a refresher course on the IOS naming conventions.