My EtherealMind» data centre

What Are 10 Gigabit Ultra Short Reach (USR) Optics ?

Greg Ferro — Sun, 20 Nov 2011 18:36:06 +0000

A couple of weeks back I posted this article comparing pricing and features on Cisco Fabric Ethernet Transceivers as a low cost option compared to 10GbaseSR SFP+ optics in when building 10GbE networks - Cisco Nexus 5000 / 2000 Pricing Bundles and Fabric Extension Transceivers (FETs) vs 10GbaseSR SFPs.

Problems With Cat6A Cables in Data Center

Greg Ferro — Mon, 14 Nov 2011 15:30:04 +0000

I was reading a white paper by Panduit that claims that 10GBaseT is suitable for use. I've been critical of Cat6A cable and believe that it's not suitable for data centre use.

L2 MultiPath Basic Design Differences

Greg Ferro — Tue, 07 Jun 2011 10:02:09 +0000

With all the talk about Layer 2 Multipath (L2MP) designs going on, I just want to point out a fundamental change in the way many people approach network design. It's seems that this point has been lost somewhere in the discussion of protocols. The Spanning Tree Protocol blocks looped paths, and in a typical networks this means that bandwidth is unevenly distributed. Of course, we might use PVST or MST to provide a rough sharing of load by splitting the spanning tree preferences for different VLANs, but the design still doesn't change overall. The basic point is that there is a LOT of bandwidth that is never evenly utilised - and that means wasted power, space and cooling (which costs more than the equipment itself).

Musing: How Many 10Gigabit Ethernet Ports Do You Really Need ?

Greg Ferro — Mon, 18 Apr 2011 22:11:53 +0000

I was doing a Data Centre Design recently and did some numbers around the numbers of 10 Gigabit Ethernet ports that need to be deployed. I got a bit of a realisation shock.

“Can I Haz a “I ? OpenFlow” Sticker Pleez” – Why, Yes, Yes I Can!

Greg Ferro — Tue, 05 Apr 2011 16:16:07 +0000

I tweeted "an I haz a "I ♥ OpenFlow" sticker pleez" - just got a call....

Rant: Why SPB Doesn’t Get Any Attention

Greg Ferro — Fri, 25 Mar 2011 18:46:38 +0000

Someone made a comment that Packet Pushers hasn't discussed SPB as alternative to TRILL or other Fabric solutions. Here's why.

PPP Show 38 – Comparing Data Centre Fabrics From Juniper, Brocade and Cisco

Greg Ferro — Fri, 25 Mar 2011 18:14:41 +0000

Kurt Bales has a customer who wants to buy a new Data Centre Network and the three main networking vendors (Juniper, Cisco & Brocade) have pitched at him and the customer. Kurt then contacted the Pushers and said "This would make a great podcast to talk about how it looks, works and the reality of the so-called "Data Centre Fabric networks, plus I've got some questions that I'd like to get some second opinions." So we rounded up Ivan from IOS Hints and Greg from EtherealMind to record a fast, furious and focussed look at the state of play with the three data centre fabrics today. Lots of speculation, wild guesses and deep diving followed. I learned heaps.

Explaining L2 Multipath in Terms of North/South, East West Bandwidth

Greg Ferro — Tue, 15 Mar 2011 20:47:59 +0000

Breaking down the definition of North/South and East/West Bandwidth with some nice pictures and examining Layer 2 Multipath and why it fits virtualisation so well.

QFabric – What Excites Me!

John McManus — Tue, 01 Mar 2011 22:47:21 +0000

I was intrigued and excited about the Junipers announcement last week of QFabric. I was vaguely aware of TRILL and Cisco implementation (Fabric Path), but came to the table (so to speak) with no pre-conceptions of what I might expect. SCI-FI ñ Is this just me? Is the ëQí in †QFabric taken from sci-fi [...]

Controller Based Networks for Data Centres

Greg Ferro — Mon, 13 Dec 2010 16:18:56 +0000

The current technologies of data centre networks don't address the fundamental scaling issues. You can't scale to hundreds of independent switches, we need to have less control planes for more coherent functions. Here is my take on next wave of networking in the data centre beyond DCB and TRILL.

Show 28 – vCloud Network Overlays, OTV, VEPA and Networking Appliances

Greg Ferro — Mon, 13 Dec 2010 16:00:00 +0000

It was planned to have a discussion around L2 Data Centre connection the VMworld in Copenhagen but Scott and I could not meetup. So we recorded this podcast to start talking about some of the issues, technology and solutions. I’m not sure that we have all the technology or knowledge in place, so keep watching [...]

The Different QoS Capabilities of the VMware vSwitch’s

Greg Ferro — Tue, 07 Dec 2010 14:08:45 +0000

A quick look at the different types of QoS available in the different switch technologies available for vSphere.

Show 27 – Layer 2 Data Centre Interconnection

Greg Ferro — Mon, 06 Dec 2010 16:00:00 +0000

Would You Implement a Proprietary L2 ECMP Protocol Today ?

Greg Ferro — Sun, 05 Dec 2010 19:58:39 +0000

So Cisco's much ballyhoo'd FabricPath protocol for "Data Centre of the Future" is proprietary. Not an extension or a fancy product name. Full 'EIGRP style' we own it and you can't have it. What's that all about ?

Show 26 – Virtual Connect – The Conversion ?

Greg Ferro — Mon, 22 Nov 2010 16:05:55 +0000

This week we are joined by Ken Henault from HP. Ken is a leader in the VirtualConnect product from HP. In the past, Greg has ranted about the the VirtualConnect product and how crap it looks so we got together to 'go at it' and see if he can be convinced that VC has value. How did it go ? ..... you be the judge.

Packet Pushers – Show 20 – Impromptu Crowdsourcing

Greg Ferro — Mon, 13 Sep 2010 07:04:15 +0000

The Pushers squeeze another show that's long on waffle, but interspersed with some very fine technical sauce. And laughter.

FCoE and Standards: This Is What Really Matters

admin — Tue, 24 Aug 2010 16:55:57 +0000

In the recent weeks, J. Michael Metz from Cisco entered a ****ing contest with my friend Greg and decided to prove that the FCoE standards are done.

Show 17 – Big Hot and Heavy Switches – Part 2

Greg Ferro — Sun, 22 Aug 2010 23:23:55 +0000

A detailed look at the Big, Hot and Heavy Ethernet Switches with a large crew to talk about their practical experiences on design, selection and performance of Cisco Nexus switches. The result ? We don't think the Nexus switches are very exciting.

Packet Pushers – Show 16 – Big Hot and Heavy Switches – Part 1

Greg Ferro — Mon, 16 Aug 2010 10:33:07 +0000

VMware “vFabric” And the Potential Impact on Data Centre Network Design

Greg Ferro — Wed, 11 Aug 2010 19:50:05 +0000

If the VMware vFabric speculation is true, then the service focussed data centre designs just got very, very, interesting.

Should a Networking Engineer Care About Servers and Storage?

admin — Wed, 04 Aug 2010 09:54:30 +0000

As you might have noticed, everyone is talking about Data Centers lately and all the new “revolutionary” networking technologies are targeted at this segment. The reason is simple: server virtualization (not to mention the vapor-word) will forever change the networking landscape and the networking engineers might get badly hurt if caught unprepared.

Runt Packet – Cisco Fabric Path

Greg Ferro — Mon, 12 Jul 2010 16:12:59 +0000

Packet Pushers are adding a new series of sporadic and occasional podcasts where we take a single topic, probably technical and very focussed and discuss just that thing. These podcasts should be about fifteen minutes and be brief and hard hitting. And we are going to call it, in Packet Pushers style ------RUNT PACKETS. So herewith is the FIRST Runt Packet.

Maximum Number of Insertions for GBICs

Greg Ferro — Fri, 09 Jul 2010 11:56:03 +0000

Ever thought about whether a GBIC has a maximum number of insertions into a transceiver ? Surprising answer follows.....

Show 10 ñ ItíS a TRILL to Cius at CiscoLiveÖ

Greg Ferro — Sun, 04 Jul 2010 19:56:41 +0000

Wow, we actually managed to do ten episodes. Jeremy Filliben, CCIE #3851 & CCDE #20090003 (@jfilliben) and Brandon Carroll, CCIE #23827 (@brandoncarroll) join the Prime Pushers for an hour-long round-table discussion of the week’s news. And if you missed Greg last week, he’s back – with rant mode decidedly ON. More on Cisco’s shipping and [...]

TRILL: Its a Deja Vu All Over Again

Ivan Pepelnjak — Tue, 01 Jun 2010 20:12:31 +0000

If youíre old enough to remember what ZX-81 was all about, youíll probably experience a weird sense of dÈj‡-vu when being exposed to the beauties of TRILL says Ivan Pepelnjak.