The Role of Code In “The New Network”
I was inspired by many little things over the past few days to begin writing a post about this whole “writing code” thing that network engineers the world over have been asking about. I’ve said before I know that most network engineers already write some kind of code - even if it’s as simple as a snippet of VBA in an Excel spreadsheet to automatically convert a spreadsheet of configuration options into an actual running configuration.The Role of Code In “The New Network”
I was inspired by many little things over the past few days to begin writing a post about this whole “writing code” thing that network engineers the world over have been asking about. I’ve said before I know that most network engineers already write some kind of code - even if it’s as simple as a snippet of VBA in an Excel spreadsheet to automatically convert a spreadsheet of configuration options into an actual running configuration.Nexus 5K L3 Daughter Card Internal Port-Channels
I was trying to configure a FEX in Rack 27, so I called it FEX 127 and was configuring Port-Channel 127 so I could vPC to the FEX. However, as soon as I entered the following, I got an error message:
NX5K-1(config-if)# channel-group 127
command failed: internally used, configuration not allowed
When you have a Nexus 5K with an L3 daughter card, the switch internally allocates Po127 and Po128 to bind the L3 interfaces to the ASICs. So if you have a 5K running L2 only, and have already allocated Po127 and Po128, and then in the future add an L3 daughter card, the system will use other free Port-Channel IDs. But if you have an L3 daughter card, you cannot use Po127 and Po128 when setting up a new Port-Channel.
The Coffee Break – Show 1
This is “The Coffee Break”. A podcast on state of the networking business where we discuss vendors moves and news, analysis on product and positioning, and look at the business of networking. It's like a soundtrack for the network industry. In the time it takes to have coffee break. Or so.The Coffee Break – Show 1
This is “The Coffee Break”. A podcast on state of the networking business where we discuss vendors moves and news, analysis on product and positioning, and look at the business of networking. It's like a soundtrack for the network industry.
In the time it takes to have coffee break. Or so.
The post The Coffee Break – Show 1 appeared first on Packet Pushers.
The Coffee Break – Show 1
This is “The Coffee Break”. A podcast on state of the networking business where we discuss vendors moves and news, analysis on product and positioning, and look at the business of networking. It's like a soundtrack for the network industry.
In the time it takes to have coffee break. Or so.
Author information
The post The Coffee Break – Show 1 appeared first on Packet Pushers Podcast and was written by Greg Ferro.
Using the Cisco CSR1000V in GNS3 With VirtualBox
The better part of a year ago when the Cisco CSR1000V was publicly released, I quickly tested the notion of running the Cloud Services Router in VMWare Fusion on the Mac, rather than on a full vSphere server. Since then, I occasionally see that some readers land on my blog after searching for the terms “CSR1000V GNS3″ looking for assistance in integrating the CSR with the popular networking simulation platform. The CSR1000V is attractive as it provides a means to run IOS-XE, the same variant as on the ASR-series routers, and unlike Dynamips, Cisco has blessed use of the CSR with the 2.5 Mb/s throughput-limited trial license as a legitimate labbing platform. Last night I decided to see if it could be done. Turns out, it’s easy.
Download the Image
The key to running the CSR1000V in GNS3 is running it in VirtualBox. Well, OK, perhaps it’s possible to get it going with QEMU as I also noticed in the release notes for the 3.11 release that Linux KVM is a supported hypervisor now, but VirtualBox seemed the path of lesser resistance to me so that’s the way I went. In order to install the CSR in a Continue reading
Flow-aware Real-time SDN Analytics (FRSA)
This article will review the slides and discuss selected topics in detail.
Using VRFs to maintain security zones in an Layer 3 datacenter network
The number of overlay technologies available today for the datacenter are numerous and highly functional. The flexibility they provide enables security zone enforcement and physical portability of hosts more seamlessly (among other benefits). However, a few risks in deploying popular layer 2 overlay technologies are vendor-lockdown, scalability, specialized hardware required to mitigate bottleneck points, and […]
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The post Using VRFs to maintain security zones in an Layer 3 datacenter network appeared first on Packet Pushers Podcast and was written by Paul Zugnoni.
FCoE versus FC Farce (I’m Tellin’ All Y’All It’s Sabotage!)
Updates 2/6/2014:
- @JohnKohler noticed that the UCS Manager screenshot used (see below) is from a UCS Emulator, not any system they used for testing.
- Evaluator Group promises answers to questions that both I and Dave Alexander (@ucs_dave) have brought up.
- Check out Dave Alexander’s take as well on the flawed Brocade study.
On my way back from South America/Antarctica, I was pointed to a bake-off/performance test commissioned by Brocade and performed by a company called Evaluator Group. It compared the performance of edge FCoE (non-multi-hop FCoE) to native 16 Gbit FC. The FCoE test was done on a Cisco UCS blade system connecting to a Brocade switch, and the FC was done on an HP C7000 chassis system connecting to the same switch. At first glance, it would seem to show that FC is superior to FCoE for a number of reasons.
I’m not a Cisco fanboy, but I am a Cisco UCS fanboy, so I took great interest in the report. (I also work for a Cisco Learning Partner as Continue reading
Introducing Community Channel – Insert Your Podcast Here
A place for anyone to start a podcast with the Packet Pushers.
The post Introducing Community Channel – Insert Your Podcast Here appeared first on Packet Pushers.
Introducing Community Channel – Insert Your Podcast Here
A place for anyone to start a podcast with the Packet Pushers.
Author information
The post Introducing Community Channel – Insert Your Podcast Here appeared first on Packet Pushers Podcast and was written by Greg Ferro.
Show 178 – Cisco Nexus 1000v and Microsoft Hyper-V
Cisco Nexus 1000V virtual switch for Microsoft Hyper-V and integrates with your existing Nexus 1000V deployment. In this episode we talk with Appaji Malla and Balaji Sivasubramanian from the Hyper-V Product team on the architecture of the product and platform.
Author information
The post Show 178 – Cisco Nexus 1000v and Microsoft Hyper-V appeared first on Packet Pushers Podcast and was written by Greg Ferro.
Using Python for HP SDN
A list of links for getting started to use Python to develop application with the HP VAN SDN Controller.
Using Python for HP SDN
A list of links for getting started to use Python to develop application with the HP VAN SDN Controller.
Docs
Tutorials
Python 2 Tutorial
Python 3 Tutorial
Codeacademy
Tools
Sublime Text
Setting up Sublime Text for Python
PyCharm - A Python IDE
hp-sdn-client library
Slides
HP VAN SDN Controller Links
Using Python for HP SDN
A list of links for getting started to use Python to develop application with the HP VAN SDN Controller.
Tab Completion on Cumulus Linux
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This film could have ended much differentlyif Jerry were running Cumulus Linux |
In the bash shell, tab completion capabilities are usually limited to helping complete:
- shell built-in commands
- external executables found in $PATH
- file names
- directory names
Completion in bash doesn't help with things like command line arguments to various commands, but it is (sometimes) smart enough to not offer filenames as completion options to the 'cd' command, choosing instead to only offer directories.
Network devices, on the other hand, tend to have really rich inline help / command completion stuff, and I live by it.
Rather than typing abbreviated commands, I prefer to let the system help me type the whole thing, partly because it eliminates errors, and partly because I usually can't remember the exact syntax for a given platform. Cisco's godawful platform-dependent mac-address-table vs. mac address-table comes immediately to mind as something that always seems to take more than one attempt.
So, rather than typing this:
ROUTER#sh ip bg vpnv4 vr Continue reading
Separating Hype from Reality in SDN
Lately, two acronyms have been making the rounds: SDN (Software Defined Networking) and ACI (Application Centric Infrastructure – promoted by Cisco). Both have things in common which equate to great marketing: a delightful vision and being difficult to pin down in terms of a crisp definition. Let me try to clarify as best I can with the disclaimer that this is purely my perspective representing Arista, as we celebrate the deployment of our second million ports of cloud networking.
The common view is that SDN is a controller or a set of network management products based on Virtualization Technologies or OpenFlow. At Arista we have a more pragmatic view. To us, SDN is a programmatic suite of open interfaces that allows applications to drive networking actions. Unlike the misconception that SDN is just a controller, I believe SDN is about scaling the control, management and data plane with programmatic and open interfaces. This means customizing the network with high-level scripting and programmatic languages, structured and machine-readable APIs, and standards-based protocols as well as interoperability with controller-friendly networks.
As we enter 2014, we are witnessing the deployment of SDN via Arista EOS and associated programmable network applications such as Advanced Telemetry, Continue reading