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Our greatest data center challenge

Cisco Live 2008 -- June 25, 2008

Data Center Network Design in a VMware environment

June 26, 2008 at 12:00 pm PST

As customers look to expand the level of server virtualization in their data centers, they often come back to us and ask what the impact will be on their data center network. This happens often enough that we locked some of our smart people and some of VMware’s smart people in a room and they came up with this design guide for deploying VI 3 and ESX Server 3.x in a Cisco network environment. To quote the introduction:”This document is intended for network architects, network engineers, and server administrators interested in understanding and deploying VMware ESX Server 3.x hosts in a Cisco data center environment.”If you have VMware in your environment, I highly suggest you check it out. The document offers comprehensive coverage of the”how it works” aspects of networking and storage and solid design best practices in a VMware environment.

What is Lossless?

In a recent post, I read that there’s no reason to wait to implement FCoE and that an underlying lossless Ethernet network is not really required. In fact, a CEO of another vendor actually proclaimed that their switch is lossless and can be used for FCoE today.In some ways, I agree. There is no reason to wait to implement FCoE today. But shouldn’t you implement it with all the features necessary for a truly lossless Ethernet? Features like Priority Flow Control (802.1Qbb), Bandwidth Management (802.1Qaz), and Congestion Management (802.1Qau)? All of these encompass what we call Data Center Ethernet and are being standardized by IEEE and supported by the Ethernet Alliance.It’s also interesting that he measures lossless capability by testing just simple forwarding on a single switch. Any modern switch can forward line-rate at different packet sizes with zero packet loss. The real question is how does an Ethernet switch handle congestion? How then does it handle storage traffic that doesn’t tolerate drops while dealing with congestion of other protocols? This is why Data Center Ethernet is required which allows you to build a lossless NETWORK, not just a lossless switch.The Cisco Nexus 5000 delivers Data Center Ethernet and FCoE today. Be sure to look at it when comparing against other so-called lossless Ethernet switches.

Happy Birthday to Data Center 3.0

June 25, 2008 at 12:00 pm PST

Well, it’s been a year since my first blog post on, which happened to be about the newly announced Data Center 3.0. As you may remember, at the time Jayshree Ullal noted that DC 3.0 was going to be a multi-year journey, which some took to mean it would be a while before we saw anything tangible to support that vision. Not quite. So if we look back at the last year, its been pretty busy on the data center front:- Cisco Catalyst VSS- 10GbE Catalyst Blade Switches for Dell, HP, and IBM blade servers- Virtual Blade Switch technology- Cisco Catalyst 4900 Switch- Ubiquitous 10GbE (core, agg, access, modular, rack, blade)- Storage Media Encryption- Data Mobility Manger- NPV/NPIV Support- The Cisco Nexus Family (7000 and 5000)- NX-OS - Data Center Ethernet- Fibre Channel over Ethernet- ACE Appliance- WAAS Mobile- WAAS Hosted Virtualization- ISV Validation from SAP, MSFT, ORCL and others- Cisco TrustSec- IronPort- VFrame 1.2 service orchestration- Data Center Network ManagerGo ahead, I’ll give you a sec to catch your breath- I think the key point is that we helped our customers move the ball forward on multiple fronts (switching, storage, security, management, apps) in the data center with a blend of investment protection of existing platforms and also the introduction of new platforms and technologies.Doug pointed out in January that there were a slew of good things in the works and we are only halfway through the year, so, stay tuned.

The funniest thing I’ve seen in a data center

Cisco Live 2008 -- June 24, 2008