How Does Internet Work - We know what is networking
I was preparing lab environment to test configuration of Source-Specific Multicast on Juniper SRX Equipment and needed a tool to generate and measure Source-Specific Multicast streams. I was aware that Iperf is a good enough tool to generate and measure multicast and unicast traffic but support for SSM was missing from current version. Fortunately there are always some developers which are interested in networking so one of them developed a special Iperf version 2.0.5 with SSM support. The idea here is to show how to make this version of Iperf work on your Cent OS or similar Linux machine. Here
I recently decided it would be fun to upgrade the hardware on my main OpenBSD machine at home (because, you know, geek). These Intel NUC machines are pretty interesting. They are pretty powerful, support a decent amount of RAM, certain models support internal storage, and they are very low power and low noise. Perfect for a machine that is a shell/email/development box.
The model I chose is the NUC6i3SYH
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OpenBSD 6.0 boots with the GENERIC kernel; no tuning or tweaking required. Full dmesg is at the end of this post. Hightlights of the hardware include:
em(4)
driveriwm(4)
driver (no support for 802.11ac in OpenBSD at the time of this writing so it’s 802.11n only)The kernel recognizes the Intel SpeedStep capabilities of the CPU and will adjust the CPU’s clock speed as needed (further keeping the power consumption of the machine at a very Continue reading
Welcome to Technology Short Take #75, the final Technology Short Take for 2016. Fortunately, it’s not the final Technology Short Take ever, as I’ll be back in 2017 with more content. Until then, here’s some data center-related articles and links for your enjoyment.
Nothing this time around!
Below is a chat session I had with Pearson Vue several months ago as I attempted to schedule a recertification exam. Apparently, I have two accounts with them and that prevents next day test scheduling. To put it mildly, I don’t think they adequately explain how they could possibly guarantee non-disclosure of data with email as a transport. Moreover, this seems to indicate a serious disconnect between security and business operations.
Image Link – for FULL Size View
I’m not going to explain the problems with this, PacketU readers understand why email is not [in and of itself] a secure method for file transport. When I experience an exchange like this, I see how segregated business practices can be and what a negative impact it can have from an information security perspective. Its not a matter of if, but a matter of when, bad things will happen as a result of not taking security seriously.
The post A Broken Process Placing Consumers at Risk appeared Continue reading
The APM unicorn seems likely to carry high expectations.
2016 has been an amazing year for Docker and the container industry. We had 3 major releases of Docker engine this year , and tremendous increase in usage. The community has been following along and contributing amazing Docker resources to help you learn and get hands-on experience. Here’s some of the top read and viewed content for the year:
Of course releases are always really popular, particularly when they fit requests we had from the community. In particular, we had:
When Microsoft made Windows 2016 generally available, people rushed to
We also provide a lot of information about how to use Docker. In particular, these posts and articles that we shared on social media were the most read:
Networking isn't the only VMware group that stands to benefit.
Since seeing the APIC-EM Path Trace demo for the first time and seeing how it represents CAPWAP, I’ve been curious how well it deals with other types of overlay/underlay networking. This article is a brief synopsis of that testing and provides some visuals around what was produced with this free management tool.
TL;DR–APIC-EM adds value to most network path traces and typically represents what it knows. The single exception is with MPLS VPNv4. If the MPLS PE nodes are pulled into the device inventory, path trace has a total lack of understanding around the recursive lookup into the global vrf that is required for VPNv4 functionality.
I wanted to start out by showing what an ideal representation of an overlay network would be for a tool like this. Path Trace understands AND clearly represents both the underlay and the overlay network for traffic flowing through a CAPWAP tunnel. The image below shows the extent of the tunnel (darker gray) and the physical components that are responsible for delivery (both through the tunnel and outside of the tunnel).
For the additional testing, I built the following topology and integrated APIC-EM into my Continue reading