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Had to implement some small but serious infrastructure.

Needed some usual things for internet operations these days like system monitoring, smart logging, graphing and alerting, high availiability, cloud, ids/ips, and mucho security.

Did this many times for random projects but this one was more serious and so I decided to rethink everything with focus on the security infrastructure. Manuals were read and quite a few quick projects were made and there is more to come so this post will be updated with time. I'll quickly go through the novel things I implemented and novel thoughs I have on the subject. This post will be a mess and there is a lot to write,

Quick logistics for nodejs apps

this is boring and already exists but I like the way I do things.

System monitoring?

munin is a collection of perl? scripts from '98 ran by crontab. UGH. nagios is.. yeah, same thing.

went with logstash -> elasticsearch -> kibana for data collection/graphing and riemann for alerting. Didn't figure out active system checks yet (a job for nagios usually. stuff like pinging, checking if websites render correctly, potentially crawling them and such)

all kinds of apps write to logstash. my node apps, log data collectors (lumberjack), local system checks IDS, and such, it works well. Data from everywhere is aggregated and graphed together. I've written something simmilar to this stack as one off apps for debugging complex architecture a bunch of times, was very happy to find out that someone actually already works on such a thing pretty seriously.

didn't like collectd as it seemed like something that hangs out in a munin/nagios oldies crowd. so I wrote:

  • a simple probe that collects data from machines locally and sends it to a central server (in my case logstash) via udp json.

it supports plugins, they are super easy to write. one of the plugins is a meta plugin that runs munin scripts because I'd rather kill myself then write all these data collectors myself.

Geographical internet stuff

csi-internet is there for you if you want to draw some computer stuff on a map. Also good to impress your girlfriend if she got used to cmatrix. As a test of a graphing engine it can ping around, do traceroutes and draw heatmaps. Messy atm as looking at pictures was more fun then looking at good code. work in progress. works on top of d3 and datamaps.


Writing tons of iptables rules is for robots and not humans and so I'd fuck it up eventually. pyromaniac is a thing that renders JSON into iptables commands.

hosts =
        ip: ''
                port: 443

        ip: ''
                port: 22,
                from: 'vpn'
                port: 666,
                from: 'all'

        ip: ''
                port: 22
                from: 'all'

        ip: ""

exports.settings =
        forward: [
            { from: 'vpn', to: 'all', comment: 'vpn to everyone TCP' }
            { from: 'vpn', to: 'all', proto: 'udp', comment: 'vpn to everyone UDP' }

    hosts: hosts

this program is highly specific to my scenario (machines behind a NAT hypervisor with strict control of each connection) I'm showing an aproach here more then sharing my code as something that will work for you.


I really like this part, but will write it up later when I have more to show

Mon Mar 16 2015 23:28:16 GMT+0100 (CET), 30 months ago

Initially I will use two different sensors for obstacle avoidance. lidar for closer range 2D image of space (obscale avoidance, scanning ground before landing, maybe SLAM)

and laser rangefinder for long range 1D distance sensing (looking for high buildings, maintaining altitude precisely, maybe high speed obstacle avoidance)

I went with cheapo robopeak hobby lidar, which seems to work well, here is a git repo for the library (node and beaglebone) (I also considered a lightweight hokuyo lidar) and for laser range finder I'll go with something like SF02 from paralax

these might be used in combination with some simple IR or just cameras (need more CPU but could double as optical flow sensors) used to locate becaons for landing or grabbing things

Ideally, both sensors should have an unobstructed front view on pitch dimension, with aditional unobstructed jaw dimension for LIDAR. Both sensors need to be able to independantly rotate on pitch axis for compensation of the angle of the drone when flying, and for scanning up and down (going in through windows, looking down when landing, etc) maybe rangefinder should also rotate on jaw axis on some fast servos for looking around independant of the drone orientation. not sure yet.


IR and ultrasound were also options, they are cheap but tricky and unreliable, (ultrasound behaves extra badly due to propeller noise on drones) These things can be compensated for, but laser rangefinding will always afaik give more accuracy and reliability at a price.

Thu Oct 09 2014 14:31:52 GMT+0200 (CEST), 35 months ago


I'm surprised I couldn't find this..

async object or json pattern matching/validation used for validating function/process arguments, api call permissions, messages, etc. supports serialization/deserialization of patterns themselves, which I used to implement a generic db query language on top of this. for now, tests are documentation

extras repository contains cuter things like

  • translation of subset of validator patterns to mongodb queries
  • validated backbone models (model that throws if certain attributes aren't set or if doesn't find appropriate superclass (for mixins))
  • validated backbone model attributes (special accessors that validate the data before its written to a model)
Fri Sep 13 2013 10:35:14 GMT+0200 (CEST), 48 months ago