Collection of useful, relevant or inane places on the the Internets for 29 Jun 2011:
- Cisco IOS Hints and Tricks: VN-Tag/802.1Qbh basics –
Cisco’s proprietary technology used in its FEX products became the basis for 802.1Qbh, an IEEE draft that is supposed to standardize the port extender architecture.
Ivan covers details relating to the upcoming 802.1Qbh/Qbg standards. As always, well done. I don’t agree about FEX being the basis for 802.1Qbh – it’s my understanding that VN-Tag is a pre-standard and proprietary version of the 802.1Qbh and FEX is the technology to make cheap switches that are similar to QFabric (but without the good bits). Refer to Ivan’s webinar for full details.
- Avaya’s MultiLink Trunk and Spanning Tree Protocol | Michael McNamara – If you’ve ever learned about vPC on Nexus, you take some time to learn about SMLT on Avaya/Nortel gear which show you how to do it right.
There was a question recently on the discussion forums regarding the ability to run Spanning Tree Protocol (STP/RSTP/MSTP) over a MultiLink Trunk (MLT). You can most certainly run STP/RSTP/MSTP over a MLT interface. You can NOT run STP/RSTP/MSTP over a SMLT interface.
I thought I would run through a few quick commands to demonstrate how to enable Spanning Tree over an MLT interface. In the spirit of making things interesting I’ll utilize Multiple Spanning Tree Protocol (MSTP) over the default legacy Spanning Tree Protocol (STP) or the optional Rapid Spanning Tree Protocols (RSTP).
- JNCIE Tips from the Field :: Summarization Made Easy « ShortestPathFirst – Stefan is now a trainer for Juniper and he is blogging up a storm on JunOS. Add him to your RSS feed.
Today we’ll start with a series of articles covering tips and techniques that might be utilized by JNCIE candidates, whether pursuing the JNCIE-SP, JNCIE-ENT, or even the JNCIE-SEC. The tips and techniques I will be covering might prove to be useful during a lab attempt but could also be used in real-world scenarios to save time and minimize configuration burden in addition to eliminating mistakes that might otherwise be made. I want everyone to understand that what I am about to write is simply a technique. I am not divulging any materials or topics which are covered under NDA.
- Cisco’s latest “Fabric”: Really? – J-Net Community – Andy Ingram from Juniper points out (in a delightfully snarky post) that Cisco’s proprietary FabricPath protocol isn’t consistently implemented across all their devices
Second, and perhaps most amusing, is Cisco’s latest use of the term “fabric.” Cisco states “the high-performance trading fabric is based on Cisco’s holistic data center fabric approach that includes the recently announced Cisco Nexus 3064 and Nexus 5500.” I am at a loss to understand how connecting 3064s and 5500s constitutes a fabric. Last summer, Cisco said its strategy for a data center fabric was based on FabricPath. But neither the Nexus 3064 nor the 5500 work with FabricPath. Earlier this year Cisco said that its strategy for a data center fabric was multi-hop FCoE. But the Nexus 3064 does not work in a multi-hop FCoE environment.
- Pluthero’s CWW turnaround looks more like a tailspin | Business | guardian.co.uk – CWW have been a miserable business partner to me:
John Pluthero does not convince as the supposed saviour of Cable & Wireless Worldwide. He has been chairman since demerger last year, overseeing the shambles of three profit warnings, the loss of a short-serving finance director and now a dividend cut.
If he knew what Jim Marsh – his successor as chief executive and long-time sidekick – was doing wrong, he had every opportunity to put him right.
Marsh has been encouraged to walk the plank with the help of £650,000 to add to the millions he has made from one of the most generous incentive schemes in UK public company history.
Frankly, if you still are doing business with CW you must be nuts.
- Among The Costs Of War: $20B In Air Conditioning : NPR –
The amount the U.S. military spends annually on air conditioning in Iraq and Afghanistan: $20.2 billion.
That’s more than NASA’s budget. It’s more than BP has paid so far for damage during the Gulf oil spill. It’s what the G-8 has pledged to help foster new democracies in Egypt and Tunisia.
- Cisco IOS Hints and Tricks: The beauties of dense-mode FCoE – I never thought of an FC SAN this way:
Traditional SAN network is a pure routed network. Every FC switch is actually a layer-3 forwarding device.
Except that FC is more like RSVP than IP since each FC device is holding state for each LUN. That’s part of the reason that FC doesn’t readily scale past a thousand or so ports. The overhead for maintaining state is significant and major failure point which impacts reliability. That’s why very few cloud companies use FC for storage – a meltdown would be catastrophic. (Oh and the price of FC is more than cloud network can pay).
- The Ghost in the Stack – Another horror story about C3750 stacking:
Well, we were wrong. As soon as switch 2 rejoined the stack and I added the config back to 2/0/24, the port-channel came up, and the pings finally succeeded. TAC never came back with any updates/bugs and we closed the case, but how annoying is that?
Cisco, if you’re listening, I’d like those 2 hours of my life back, please. I’ve included the relevant snippets of code below in case you’re interested.
- MobileMe: How to move an iWeb site from MobileMe to another web hosting service – Apple Support artcile
This article explains how to move an iWeb site, including one with a personal domain, from MobileMe to another web hosting service.
If you have family with Macs, it’s a good chance you are going to need to knowthis.
- HP Blogs – Network evolution: the Hierarchy of Networking Nee… – The HP Blog Hub -Alvaro Retana takes on Maslow’s Hierarachy of Needs and maps network needs into a pyramid. I agree with the idea although not exactly the layout.
As in Maslow’s theory, the basic level of needs must be satisfied before we can go on to want or explore the higher levels. The first couple of layers represent operations and security needs that are basic to any network. From there is where we go into having the network understand the applications and their users, prioritize them and finally dynamically adapt to all this. I realize that most of what I’m mentioning as needs can be done through configuration – efforts such as OpenFlow are also trying to make the programmability of the network easier.
Also worth noting, that Alvaro Retana was previosluy at Cisco and co-author of Optimal Routing Design, Adv IP Network Design with Russ White. The exodus from Cisco to HP seems to continue.