Route Analytics in the Age of SDN – Now, More than Ever.
Route Analytics in the Age of SDN - Now, More than Ever.
by Brian Boyko, Technology Commentator - April 1, 2014
One of the biggest problems that may delay widespread SDN adoption is not a problem of coding or engineering, but one of poetry.
Network management is about logic and reason, but our nomenclature was written by poets. Even the word “networking” calls to the image a “netting work” - like you would find on a hammock or trapeze artist's safety net. We talk about network “pipes,” and conjure throughput like liquid water flowing through Roman aqueducts or modern PVC piping. We think of the “flow” of data through those pipes, though the only “fluid” is the movement of electrons – if that.
Metaphors that are inelegant or uninformative (“Information Superhighway” for example) fail.
Which is why SDN can be hard to envision. Intellectually, we know that it is about separating the control of where data is sent and the hardware that actually sends it. But what metaphor can we conjure that makes sense to explain this concept?
This is a problem for poets.
One metaphor that was recently used in IT Business Edge was the idea of “relying Continue reading
FCC Eases Restrictions on 5GHz UNII-1 Band
The FCC just made an unofficial news release of pending action that was approved at today's commission hearing which eases restrictions on the existing 5 GHz UNII-1 frequency band (5.150-5.250 GHz, Wi-Fi channels 36-48).To quote from the news release (emphasis added by me):
By its action the Commission significantly increased the utility of the 100 megahertz of spectrum, and streamlined existing rules and equipment authorization procedures for devices throughout the 5 GHz band.This ruling makes the following changes to the UNII-1 band:
- Removes restriction on indoor use. Now the UNII-1 band can be used outdoors as well. This will allow use of the band by WISPs and for outdoor hotspot deployments which are rapidly growing with the support of telecommunications and cable operators.
- Increases the allowed power output. The power output had been lower in UNII-1 than other 5 GHz UNII bands due to indoor-only use (50mW IR, 200mW EIRP). Exact details of the new power limits have not been released, but it is fair to assume the UNII-1 band will have similarly capable power output as
UNII-2/2e bands (250mW IR, 1W EIRP)the UNII-3 band (1W IR, 4W EIRP). (Update after reviewing Commissioner Rosenworcel's Continue reading
The Packet Pushers At Dell’s Interop Booth Tuesday & Wednesday @ 3:45pm
The Dell networking team has asked the Packet Pushers to co-host a couple of Interop sessions at their booth. Greg Ferro and Ethan Banks will be at the Dell booth on Tuesday, 1-April and Wednesday, 2-April at 3:45pm. In the Tuesday session, we’ll be discussing the new Dell Z9500. In the Wednesday session, we’ll discuss […]
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The post The Packet Pushers At Dell’s Interop Booth Tuesday & Wednesday @ 3:45pm appeared first on Packet Pushers Podcast and was written by Ethan Banks.
Beware the Ides of March: Subsea Cable Cut Trend Continues
Earlier this month, the International Cable Protection Committee, a submarine cable advisory group, held their annual plenary in Dubai. One question that they could have considered is: Why do so many submarine cables get cut in the February/March timeframe? In this blog, we’ll look back at the last three years and the submarine cable industry’s own version of March Madness.
2012
Two years ago in February 2012, we saw a rash of closely-timed submarine cable cuts, causing Internet disruptions extending into March. In one incident, three cables were simultaneously severed in the Red Sea on February 17th, and then a fourth was damaged on the 25th off the coast of Kenya. The fourth cable was the TEAMS (The East African Marine System) cable systems, which runs from Mombasa to Fujairah, UAE.
| We detailed the impact of the TEAMS cable break here, noting the resilience of many East African providers, who had purchased redundant capacity on the other two East African submarine cables: EASSy and SEACOM. The TEAMS cable would experience a second cut just weeks after it was repaired, which led TEAMS to threaten a lawsuit against the Kenya Ports Authority (KPA) over the repeated damage caused by Continue reading |
Show 185 – Vendor Product Management
How do vendors decide to make network products ? What is the process and thinking behind what happens inside the wall of the vendor ? Today, Greg is join by Omar Sultan from Cisco to talk broadly about how vendors make big decisions
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The post Show 185 – Vendor Product Management appeared first on Packet Pushers Podcast and was written by Greg Ferro.
FCoE, 10GBaseT and BER – problem managed
Some time ago I wrote that FCoE would have problems on 10GBaseT due to relatively high error rates of 10GBaseT deployment. New information suggests that this problem is solved under certain circumstances.
The post FCoE, 10GBaseT and BER – problem managed appeared first on EtherealMind.
Custom DHCP server configuration on Opengear
For the last few years I've run my home DHCP service on a virtual private server at AWS.This was not a great idea. It's a pain to resolve issues with my Internet service when those issues cause my laptop to stop getting an IP address assigned because the path between my house and the DHCP server has been interrupted.
The service is at Amazon because I wanted to purge "server" like things from the house, but its clear that I needed to bring DHCPd back home. I started investigating moving the service to one of my Opengear ACM5000 units, which is always running anyway because it keeps tabs on my generator and home security system, sends me text messages about interesting events and whatnot.
The Opengear web UI doesn't offer too many DHCP service configuration options, but I didn't expect that to be a problem. One of the things I love about Opengear is that most anywhere you look, the baked-in scripts and configuration elements can be replaced with user-supplied versions of those things.
I'd expected to find something like include /etc/config/dhcpd-user.conf in the automagically-generated DHCPd configuration, but it wasn't there.
Healthy Paranoia Show 23: Phone Phreaking, Hacking and Fraud, Oh My!
That’s right listeners, you’re not in Kansas anymore! It’s time to follow that Yellow Brick Road to another episode of Healthy Paranoia. Today, we’ll be discussing phone phreaking, hacking and fraud, oh my! So we’re off to see Wizard, the Wonderful Wizard of VoIP security, Patrick McNeil. Joining me over the rainbow for this trip […]
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The post Healthy Paranoia Show 23: Phone Phreaking, Hacking and Fraud, Oh My! appeared first on Packet Pushers Podcast and was written by Mrs. Y.
Turkish Internet Censorship Takes a New Turn
Internet censorship in Turkey took a new and ominous turn yesterday. In order to better seal off access to social media sites like YouTube and Twitter, the incumbent TurkTelecom began hijacking the IP address space of public DNS resolvers like those of Google. This allows TurkTelecom servers to masquerade as Google DNS servers, returning whatever answers they want. Under normal circumstances, such queries would have been destined for servers outside the country, which is how Turkish users were circumventing the ban on YouTube imposed earlier this week. However, now local users of these global DNS services are surreptitiously redirected to alternate providers within TurkTelekom. You can see this route redirection for yourself, here and here.
Recap
Turkey’s 25th and current Prime Minister, Recep Tayyip Erdoğan, has publicly and repeatedly expressed his dislike of social media, instructing various sites to be blocked. The current attempt to curtail this important medium began on March 21st via DNS poisoning of Twitter by Turkish ISPs, probably trying to implement the government-mandated ban in a minimally invasive way.
Twitter blocked in Turkey via local DNS poisoning, global DNS providers not impacted: http://t.co/qFEBPXAho8 pic.twitter.com/JDL8SNv62G
— Renesys Corporation (@renesys) March 21, 2014
But Continue reading
Turkey Hijacking IP addresses for popular Global DNS providers
At BGPmon we see numerous BGP hijacks every single day, some are interesting because of the size and scale of the hijack or as we’ve seen today because of the targeted hijacked prefixes.
It all started last weekend when the Turkish president ordered the censorship of twitter.com. This started with a block of twitter by returning false twitter IP addresses by Turk Telekom DNS servers. Soon users in Turkey discovered that changing DNS providers to Google DNS or OpenDNS was a good method of bypassing the censorship.
But as of around 9am UTC today (Saturday March 29) this changed when Turk Telekom started to hijack the IP address for popular free and open DNS providers such as Google’s 8.8.8.8, OpenDNS’ 208.67.222.222 and Level3’s 4.2.2.2.
BGP hijack
Using the Turk Telekom looking glass we can see that AS9121 (Turk Telekom) has specific /32 routes for these IP addresses. Since this is the most specific route possible for an IPv4 address, this route will always be selected and the result is that traffic for this IP address is sent to this new bogus route.
Turk Telekom route server displaying the Continue reading
Network Test Automation with Ansible
In the last post, I talked about how Ansible could be used for various forms of network automation. In the comments, Michael asked if Ansible could also be used for network test automation and verification. Since I’m just starting to explore Ansible, I figured why not try it out. The short answer is, it’s possible. Let’s take a look at an example proving this out.
I just built a playbook that verifies a router, or group of routers, has reachability to a defined list of destinations. Maybe you are deploying a new site? Maybe a new host? Is the route being sent correctly to all sites? Now, a playbook like this can be used to ensure every site (from the router) has reachability to the new site, subnet, or host. You define the destination. Cool, right?
Update: Before reading anymore, it's recommended to read the first post on Ansible for Networking.
Let’s do a quick walk through.
Here is the playbook.
Update: Before reading anymore, it's recommended to read the first post on Ansible for Networking.
Let’s do a quick walk through.
Here is the playbook.
As you can see, there is not a lot to it. This playbook that we are looking at, called ‘pinger’, is using a module called ‘auto_pinger’. Continue reading
Over Layer Versus Under Layer
Do you feel like you are in data center acronym soup these days? I sure feel it, and I think sometimes tech-speak can help mask the real driver for change. In the data center, we are striving for a new model. The idea of real time resource allocation and reallocation, the ideal organism that responds perfectly to every request and oh, did I mention resiliency in the whole stack for instant recovery from any fault. Wow, that would be great! I think we have a ways to go. For now, the latest craze is to add the word virtualization to each topic.
Why is that? I think it is because virtualization has helped us learn that you can decouple the hardware and software and create layers of abstraction that lead to better systems. And here “better” could be lower power / cooling and space utilization, or it could the idea that a virtual machine (VM) can be your 18 wheeler, or container ship, and move the application
or data anywhere you want, to help in that resource allocation / re allocation or resiliency story I mentioned above.
Now if we look on the network side, Continue reading
When Good NICs Do Bad Things: A Blast of IPv6 Multicast Listener Discovery Queries
This is the write-up of a recent event we experienced on our network. This will be combination of a journal of symptoms, troubleshooting steps taken, and a brief overview of the environment and platforms involved. This isn’t a forensic analysis of the cause or of different behaviors in various environments. Rather, it’s meant to be […]
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Internets of Interest for 28th March 2014
Collection of useful, relevant or just fun places on the Internets for 28th March 2014 and a bit commentary about what I’ve found interesting about them: Brocade – Brocade Extends Ethernet Fabric Leadership – Brocade hasn’t given up on the Campus. This announcement from February talks about their switch platform, most interesting is that […]
The post Internets of Interest for 28th March 2014 appeared first on EtherealMind.
Cisco Internal VLAN Usage
About a month ago I worked on an old CatOS switch. Working on this switch reminded me about some of the differences between CatOS and IOS. One of the big differences is how a Layer 3 routed interface is configured between the two OS versions. On a Catalyst running IOS, it is almost identical as […]
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The post Cisco Internal VLAN Usage appeared first on Packet Pushers Podcast and was written by Charles Galler.
Does Network Lifecycle Management Make Sense?
Recently, we met with a friend who has done an amazing job of understanding the lifecycle management of virtual machines (VMs). As the CTO of a very large cloud provider, he explained in deep detail how he took advantage of Moore’s Law and doubled the amount of VMs in each rack each year, while maintaining or shrinking the cost per rack. As a result, he has doubled the amount of earning potential in each data center while driving cost down, even as his staff is ripping out servers long before their traditional three- to four-year lifecycle and purchasing new ones. He is buying servers at a 3-to-1 ratio over a three-year period when compared with a typical server lifecycle, yet his cost to operate the data center is going down and his productivity is going up by 2x every year. Amazing!
While we enjoyed learning of his success, when we hear these stories, we think “Could this have the same type of impact somewhere in the network?” It got us to ask why customers traditionally hang on to their top-of-rack switches for four or five years and sometimes longer.
What is different about the network versus servers?
Obviously, Continue reading
SAN Automation with Python and Jinja
One of my least favorite things to do in my day job is create or maintain a zoning configuration on a fibre channel switch, such as a Cisco Nexus or MDS. It’s tedious, very error prone, and annoying when changes need to be made. I wrote earlier in the week on the value of using a templating language like Jinja to define the structure of a switch configuration, but dynamic enough to accept all kinds of input from some higher-level intelligence elsewhere.SAN Automation with Python and Jinja
One of my least favorite things to do in my day job is create or maintain a zoning configuration on a fibre channel switch, such as a Cisco Nexus or MDS. It’s tedious, very error prone, and annoying when changes need to be made. I wrote earlier in the week on the value of using a templating language like Jinja to define the structure of a switch configuration, but dynamic enough to accept all kinds of input from some higher-level intelligence elsewhere.How to become a network engineer
Original content from Roger's CCIE Blog Tracking the journey towards getting the ultimate Cisco Certification. The Routing & Switching Lab Exam
If you have arrived on this page then I would assume you know what a network engineer is and would like to find out how to become a network engineer? If you are not sure what a network engineer is or does then the picture below explains it very well Picture courtesy of http://perceptionvsfact.com/ A […]
Post taken from CCIE Blog
Original post How to become a network engineer