Category: data center

Pirmin Sidler read the stretched VSAN blog posts by Duncan Epping (intro, HA/DRS considerations, demo) and asked me what I think about stretched VSAN considering my opinions on long-distance vMotion.

TL&DR answer: it makes way more sense than long-distance vMotion. However…

One of my readers stumbled upon blog post from 2011 explaining the potential implementations of VXLAN hardware gateways, and asked me if that information is still relevant.

I knew that I’d included tons of information in the Data Center Fabrics and VXLAN Deep Dive webinars, but couldn’t find anything on the web, so I decided to fix that in 2015.

TL;DR: Gabi Gerber from Data Center Interest Group Switzerland (DIGS) is organizing a day-long Data Center event on September 16th, and invited me (again) as the keynote speaker. Do drop by to discuss data center design and automation challenges.

Sometimes it seems like the networking vendors try to (A) create solutions in search of problems, (B) boil the ocean, (C) solve the scalability problems of Google or Amazon instead of focusing on real-life scenarios or (D) all of the above.

Bryan Stiekes from HP decided to do a step in the right direction: let’s ask the customers how complex their data centers really are. He created a data center complexity survey and promised to share the results with me (and you), so please do spend a few minutes of your time filling it in. Thank you!

A few days ago I had a nice chat with Christoph Jaggi about private and public clouds, and the mistakes you can make when building a private cloud – the topics we’ll be discussing in the Designing Infrastructure for Private Clouds workshop @ Data Center Day in Berne in mid-September.

The German version of our talk has been published on Inside-IT; those of you not fluent in German will find the English version below.

Robin Harris described an interesting problem in his latest blog post: while you can reduce the storage access time from milliseconds to microseconds, the whole software stack riding on top still takes over 100 milliseconds to respond. Sometimes we’re optimizing the wrong part of the stack.

Any resemblance to SDN in enterprises or the magical cost-reduction properties of multi-vendor data center fabrics is obviously purely coincidental.

After introducing the concepts of Cumulus Linux in the Data Center Fabrics update session, Dinesh Dutt described the typical data center architectures implemented with Cumulus Linux and the lessons everyone should learn from large-scale web properties.

In the Can Virtual Routers Compete with Physical Hardware blog post I mentioned that SSL termination remains one of the few bastions of hardware acceleration.

Based on the comment made by RPM, it looks like I was wrong.

Here’s his reasoning:

With the advent of layer-3 leaf-and-spine data center fabrics, it became (almost) possible to build pure layer-3-only data center networks… if only the networking vendors would do the very last step and make every server-to-ToR interface a layer-3 interface. Cumulus decided to do just that.

In May 2015 I invited Dinesh Dutt to talk about Cumulus Linux and its typical use cases on an update session of the Data Center Fabrics Architecture webinar.

As expected, he started with the big picture: what are Cumulus Networks and Cumulus Linux all about?

One of my readers sent me an interesting reliability design question. It all started with a catastrophic WAN failure:

Once a particular volume of encrypted traffic was reached the data center WAN edge router crashed, and then the backup router took over, which also crashed. The traffic then failed over to the second DC, and you can guess what happened then...

Obviously they’re now trying to redesign the network to avoid such failures.

Gabi Gerber (the wonderful mastermind behind the Data Center Day event) is helping me bring my Designing Infrastructure for Private Clouds workshop (one of the best Interop 2015 workshops) to Switzerland.

This is the only cloud design workshop I’m running in Europe in 2015. If you’d like to attend it, this is your only chance – register NOW.

At least a dozen engineers sent me emails or tweets mentioning Project Calico in the last few weeks – obviously the project is getting some real traction, so it was high time to look at what it’s all about.

TL&DR: Project Calico is yet another virtual networking implementation that’s a perfect fit for a particular use case, but falters when encountering the morass of edge cases.

One of my readers wondered whether one still needs traditional firewalls in microsegmented environments like VMware NSX.

As always, it depends.

During the Cumulus Linux presentation Dinesh Dutt had at Data Center Fabrics webinar, someone asked an unexpected question: “Do you have In-Service Software Upgrade (ISSU) on Cumulus Linux” and we both went like “What? Why?”

Dinesh is an honest engineer and answered: “No, we don’t do it” with absolutely no hesitation, but we both kept wondering, “Why exactly would you want to do that?”