Category: Data Center

Randall Greer left a comment on my Revisited: Layer-2 DCI over VXLAN post saying:

Could you please elaborate on how VXLAN is a better option than OTV? As far as I can see, OTV doesn't suffer from the traffic tromboning you get from VXLAN. Sure you have to stretch your VLANs, but you're protected from bridging failures going over your DCI. OTV is also able to have multiple edge devices per site, so there's no single failure domain. It's even integrated with LISP to mitigate any sub-optimal traffic flows.

Before going through the individual points, let’s focus on the big picture: the failure domains.

In July I wrote about an Amazon Kindle version of my Data Center Design Case Studies book and complained about their royalties model. Someone quickly pointed out how to adapt to their system: split the book into multiple volumes and charge $9.99 for each.

It took me months to get there, but the first two volumes are finally on Amazon:

During one of my ExpertExpress engagements I got an interesting question: “could we replace a pair of central firewalls with iptables on the Linux server?”

Short answer: Maybe (depending on your security policy), but I’d still love to see some baseline scrubbing before the traffic hits the server – after all, if someone pwns your server, he’ll quickly turn off iptables.

During the last round of polishing of my Designing Infrastructure for Private Clouds Interop New York session (also available in webinar format) I wondered whether one could use the recently-launched UCS Mini to build my sample private cloud.

A while ago Cisco added dynamic FCoE support to Nexus 5000 switches. It sounded interesting and I wanted to talk about it in my Data Center Fabrics update session, but I couldn’t find any documentation at that time.

In the meantime, the Configuring Dynamic FCoE Using FabricPath configuration guide appeared on Cisco’s web site and J Metz wrote a lengthly blog post explaining how it all works, triggering a severe attack of déjà vu.

When we were discussing my autumn travel plans, my lovely wife asked me “What are you going to talk about in Bern?” She has a technical background, but I didn’t feel like going into the intricacies of SDN, SDDC and NetOps, so I told her the essence of my keynote speech:

A while ago Rick Parker told me about his amazing project: he started a meetup group that will build a reference private/hybrid cloud heavily relying on virtualized network services, and publish all documentation related to their effort, from high-level architecture to device and software configurations, and wiring plans.

In Episode 8 of Software Gone Wild Rick told us more about his project, and we simply couldn’t avoid a long list of topics including:

A reader sent me this question:

My company will have 10GE dark fiber across our DCs with possibly OTV as the DCI. The VM team has also expressed interest in DC-to-DC vMotion (<4ms). Based on your blogs it looks like overall you don't recommend long-distance vMotion across DCI. Will the "Data Center trilogy" package be the right fit to help me better understand why?

Unfortunately, long-distance vMotion seems to be a persistent craze that peaks with a predicable period of approximately 12 months, and while it seems nothing can inoculate your peers against it, having technical arguments might help.

Building a private cloud infrastructure tends to be a cumbersome process: even if you do it right, you oft have to deal with four to six different components: orchestration system, hypervisors, servers, storage arrays, networking infrastructure, and network services appliances.

A few days ago I had an interesting interview with Christoph Jaggi discussing the challenges, changes in mindsets and processes, and other “minor details” one must undertake to gain something from the SDDC concepts. The German version of the interview is published on Inside-IT.ch; you’ll find the English version below.