Collection of useful, relevant or inane places on the the Internets for 15 Nov 2011:
- Coding Relic: The Computer is the Network – Very well thought out piece of the current poor quality of software switching
Software defined networks are a wonderful thing, but development of an SDN agent to drive an existing ASIC does not suddenly make it capable of packet handling it wasn’t already designed to do. At best, it might expose functions of which the hardware was always capable but had not been utilized by the older software. Yet even that is questionable: once a platform goes into production, the expertise necessary to thoroughly test and develop bug workarounds for ASIC functionality rapidly disperses to work on new designs. If part of the functionality isn’t ready at introduction it is often removed from the documentation and retargeted as a feature of the next chip.
- Software Bug ToolKit – Cisco Bug report for Mac and AnyConnect not working:
Symptom: AnyConnect 3.x for Mac gets “Certificate Validation Failure”
Conditions: AnyConnect 3.x for Mac connecting to ASA running 8.4 and using certificates to authenticate.
Workaround: Downgrade ASA to 8.3
This seems like a failure of the testing process. How can you ship a version of code that misses such a simple and vital part of your security strategy ? Another sign that Cisco doesn’t take code testing and validation seriously.
- The “ip subnet-zero” Command – A reminder of old time IP requirements.
For those who haven’t worked with IOS versions prior to 12.0, the ip subnet-zero command might be quite mysterious. It is actually straightforward and easy to grasp. First though, a little background must be discussed. Most importantly to understanding this command is the definition of a zero subnet. To understand this, let’s review what a subnet actually is.
- VTP Client Mode – It Can Still Wipe Out Your VTP Server! | Echo .. Reply Packets!!!!! – Detailed blog post on the perils of VTP and why you need to careful. With great power comes risk – excellent summary of entry level information.
Now, I’m not making this stuff up! This stuff happens all the time! The rule of thumb is that you should always reset the revision number to 0 on any switch before putting it into production. Whether it’s going to be a VTP Server, Client or in Transparent mode, it’s best to start fresh. If we follow this best practice we would never end up in the very unintentional situation like above.
- The data center gets its first 100 Gbps optical chip — Tech News and Analysis – This article talks about the new optoelectronics for 100GbE. This is important since it’s a building block for cost effective 100 Gigabit networks. By combining the optical and the silicon we have an effective pathway for upgrades!!!
The ascendancy of fiber isn’t just happening in our home broadband and long-haul networks, but also must occur inside the data center and even on the chips themselves as we demand more from our computers and networks. Luxtera’s chip helps usher in the age of light inside the data center in a way that doesn’t require the replacement of all the existing gear. Luxtera will sample the chips this year with the chips supporting both Ethernet and Infiniband applications.
Bring. It. On.
- OSX:Awaken and TimeBoxed Time App Reviews — Greg Ferro – Notational Stigma – I reviewed some time tools here
You might think that OSX would have a decent clock application but it’s does not. Recently, I’ve started using the Pomodoro technique of timing my concentration bursts on a specific topic. Partly to retrain my habit of constant attention shifting and partly to find a smarter way of working. I have two apps on my Mac that I use to help with this process.
- NMIS Configuration Part 1 – NMIS is my “go to” Network Management platform. I like Solarwinds and some of the other commercial products but NMIS works the way I think. Here is the first part of an article on setting up NMIS for the first time, and follow the links to two more articles.
- “Virtual Connect for DUMMIES®” 2nd Edition; Going Global – HP releases Virtual Connect for Dummies Version 2. Integration between the different business units seems to be improving & Virtual Connect is getting better as a coherent product set. It’s not as integrated or capable as Cisco UCS networking but it’s starting to live up to it’s promise.