Category Archives: Technical

Application Monitoring with ThousandEyes

In a prior post, I showed off ThousandEyes and how one of my clients uses it to monitor the BGP routing of their IP prefix. The same client also uses ThousandEyes for monitoring the web apps they host for their customers. Read on to see more about what ThousandEyes does for them!

Continue reading

Advertisements
Tagged , ,

Migrating My Home Network to a Virtual Firewall Appliance

Recently, I built myself a nice VMWare vSphere server. I’ll cover the server setup itself in more detail sometime, but once I got it kicking I decided I should find some novel (for me, at least) ways to use it. As I looked around my home network trying to find improvements to make with the vast powers of virtualization, my gaze settled on my little Cisco ASA5505 home firewall.

Continue reading

Tagged , , , , ,

998 Extra Eyes on Your Applications

Last September one of the vendors that presented at Networking Field Day 6 was ThousandEyes, a San Francisco-based company founded in 2010 where the startup vibe thrived.
Tagged , , ,

Cisco Application Centric Infrastructure: Nexus 9000

On November 6, I was fortunate to attend the Cisco Application Centric Infrastructure launch event in New York City as part of the Tech Field Day blogger delegation. This event was the much-anticipated unveiling (and acquisition announcement) of Insieme Networks, Cisco’s “SDN Spin-in” which maintained a pretty impressive amount of secrecy over its relatively short existence. The main keynote/announcement event consisted of a lot of flashy marketing videos and various tech executives praising each others’ companies. The tech press has been atwitter with coverage on Cisco’s ACI strategy and various components. I’m not going to try to recap the entire announcement, as others have done a much better job of that than I could, but I’m going to provide my take on each of what I considered to be four related, but somewhat distinct announcements that day. In this post, I cover the Nexus 9000 line of switches.
Tagged , , ,

Why Can’t I Upgrade My ASA to 9.1.3?

I ran into an unexpected issue the other day that kept me scratching my head for a few minutes when a new ASA refused to take a code upgrade. Read on for the details.

Continue reading

Tagged ,

Big Switch Networks and the (possible) Future of Networking Hardware

BSN-SDN-approach

Over the last couple of years, two major philosophies for SDN have evolved which I will call the overlay model, and the flow programmability model. Overlay networks are the notion of building multiple virtual networks in parallel on top of a physical network fabric, using some means of separating the virtual networks — typically an encapsulation method like VXLAN or NVGRE. Then we have the “flow programmability” model, based on the idea of programming SDN behaviors on a flow-by-flow basis into your existing (or new) physical and virtual network switches using a protocol like OpenFlow.

Continue reading

Tagged , , ,

Spirent Avalanche NEXT – Making Network Testing Approachable

During the week of Network Field Day 6, Spirent announced the Avalanche NEXT product line. Our first NFD6 session was at Spirent’s office in Sunnyvale.

Last time I used Spirent products (admittedly about 10 years ago), the interface was a complex, clunky Windows application. You had to hand-craft frames that would have (at best) a very predictable value iteration in various packet fields (increase a payload field by “1” or “2” per packet). Frankly, this didn’t work well. TCP sessions didn’t work at all, and simulating more than a couple flows simultaneously was so time-consuming that it had no value. You could test raw throughput, but nothing (helpful) above layer 3.

While I realize that Spirent’s products have evolved in the interceding decade, the introduction of the Avalanche NEXT brings a lot of changes.

Continue reading

Tagged , , ,

The Confluence of Experience and Expertise

Recently I was called out to one of my customers, a local college, which had been fighting a variety of disruptive network issues for several days following a campus-wide power-down. After a short phone call, we agreed that I’d better get out there and take a look first-hand at what was going on. Remote work is almost always an option, but I always feel that getting my eyes directly on a problem helps. Sometimes I feel like “The Network Whisperer” when I get out to a customer in trouble — something just speaks to me and points me in the right direction.

Continue reading

Tagged , ,

Removing BGP Private ASNs – Revisited!

Reader Feedback!

Recently, I posted about some lab verification I did during a customer setup where I had to strip private BGP AS numbers (64512-65535) before sending BGP-learned prefixes upstream to an ISP.

While I used the purpose-built “remove-private-as” neighbor command, several readers commented to me via the blog and via Twitter with some ideas for alternate solutions. They even got me thinking about an idea of my own.

Continue reading

Tagged ,

Removing Private BGP ASNs and the Importance of Lab Validation

I have an interesting project going on with two of my customers. One of them is buying a web-hosting business from the other, and we have to migrate all of the resources (including IP space) from one organization to the other in the same colo. Of course there is a lot involved with this, but one of the things we had to consider was the routing. For the short term (the next few months), the company buying the hosting business (let’s call them BUYER, Inc), will not have its own Internet connection from the colo, but will instead transit through the selling company (we’ll call them SELLER Corp.).

Continue reading

Tagged ,
Advertisements
@greatwhitetec

Virtualization, Storage, and other techy stuff

The Stupid Engineer

I ask those questions you're too clever to.

Sunay Tripathi's Blog

Pluribus Networks Founder's Blog on OS, Networking, Virtualization, Cloud Computing, Solaris Architecture, etc

Ed Koehler's Blog

Just another WordPress.com weblog

JGS.io

Data networking, stray thoughts, nerdy fun...

Network Heresy

Tales of the network reformation

The Borg Queen

Jottings on the intersection of tech and humanness

Networking From The Trenches

Ramblings about my thoughts, experiences, and ideas.

In Search of Tech

Looking for the next big thing.

Networking 40,000

Attaining my CCIE with the help of Warhammer 40k

stubby router

just another networking blog

Ronnie Angello

Network Architect . CCIE 17846 . CCDE 2012::1

Network Shenanigans

Making Packets Do Silly Things

It must be the network...

Jonathan Davis (@subnetwork) keeps layers 1-7 working so that Layer 8 can be productive.