Troubleshooting: ICMP Host Unreachable

By | Network Engineering, Troubleshooting, Uncategorized | No Comments

This article has two messages to deliver. The first being the technical piece where I review what the ICMP message means and what we tried to resolve the issue.  The second is to illustrate the methodology used. I wanted to make those statements because in the past, some readers tend to concentrate too much on the technical information and gloss over the methodology part of the article. Read More

Have you insured 100% of your infrastructure or just parts of it?

By | End user monitoring, Network Engineering, Network Monitoring, Uncategorized | No Comments

agentMany see IT investment in monitoring tools as a cost since it doesn’t produce any explicit revenue. However, in today’s world where network connectivity and online presence is a central pillar for just about every business, it becomes apparent that any downtime has an immediate revenue impact associated with it. Either because your online store is down or your employees cannot get their jobs done. Let alone the reputation damage that comes with every period of major system downtime. Read More

Home ISP performance monitoring with BISmark

By | Distributed network monitoring, End user monitoring, Network Engineering, Raspberry Pi, Uncategorized | No Comments

bismark mapA couple of months ago I blogged about using Raspberry Pi’s as home network monitoring agents. The idea was to collect data from home networks and compare the performance of different ISP’s as well as detect outages and get notified about them. Guess what? There is nothing new under the sun: project BISmark does exactly that!

BISmark stands for Broadband Internet Service Benchmark, and is a research project between Georgia Tech and Princeton University. It started by utilizing OpenWrt routers. In addition, it now it supports Android devices as well asRaspberry Pi’s. The project started around 2011.Currently BISmark has 406 devices registered, although only 58 appear active. Read More

NetNORAD: Active network monitoring at Facebook

By | Distributed network monitoring, Network Engineering, Network Monitoring, Troubleshooting, Uncategorized | No Comments

Active monifacebook-data-centertoring of data centers is nothing new to NetBeez. In a previous post, I showed how leaf-and-spine data centers based on Cumulus Linux can be monitored with NetBeez. I also wrote about how Microsoft is monitoring its data centers with an active probing system called Pingmesh. You may not be surprised to know that Facebook is doing something similar with an in-house system called NetNORAD, which enables the infrastructure team to quickly troubleshoot its massive data center networks via end-to-end probing.
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Raspberry Pi 3 & iPerf

By | Network Engineering, Network Monitoring, Raspberry Pi, Uncategorized | One Comment

plotIt’s been four years since the release of the Raspberry Pi platform, and the excitement for each new version hasn’t diminished! Two weeks ago, the Raspberry Pi Foundation announced the release of the Raspberry Pi 3. The most notable upgrades are the on-board WiFi and Bluetooth support, as well as the more powerful 64-bit ARM quad-core processor.

For us, networking and Raspberry Pi junkies, these are great news. At NetBeez, we use the Raspberry Pi as our main platform for wired and wireless monitoring and already started testing the Raspberry Pi 3. In this post I will compare the Raspberry Pi 3 to Raspberry Pi 2 with respect to iPerf performance. Read More