Tech

Logs are useful, I'd even say the most important thing for Sysadmins and Network Admins and often Developers also. So I'm surprised why I took so long to implement a central log collection for my network. I use Mikrotik which Operating System is called RouterOS. In RouterOS you go to System > Logging to configure remote logging. First add (+) a new item to Actions /system logging action add name="rsyslog" target=remote remote=192.168.2.1 remote-port=514; Add a rule for every type of event you want to send to the remote logger. system logging add topics=info action=rsyslog; system logging add topics=error action=rsyslog; system ...
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Comprobando 15M IPs Paraguayas por CVE-2018-14847
Disclaimer: S贸lo quiero aclarar que ning煤n sistema fue comprometido y ninguna intrusi贸n fuera del margen legal ha sido cometida en relaci贸n a este experimento. Este post es para fines educacionales. El autor no asume ning煤n tipo de responsabilidad en relaci贸n al uso del material expuesto.
Hace poco se descubri贸 una vulnerabilidad (CVE-2018-14847) en RouterOS, el firmware de los routers de la marca Mikrotik. La vulnerabilidad consiste en un 鈥渁uthentication bypass.鈥 B谩sicamente es tan simple que es rid铆culo, no deber铆a hacer pasado pero, suelen suceder este tipo de cosas en la inform谩tica.
Funciona de esta manera. Mikrotik usa una aplicaci贸n llamada ...
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How to disable Samsung's annoying Bloatware
If there is something that infuriates me it is bloatware that cannot be disabled. I happened to get a notification every few minutes from "Samsung Experience Service" for the last couple of weeks. There was no way to disable that shit. I found online forums full of complaints. Good job Samsung you are alienating your clients.
Ok so let's get rid of this. The first step is to download ADB. Open the command prompt and switching to the directory where adb.exe is located. Make sure your Samsung is connected to the PC and click on Allow USB Debugging. You find ...
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Keynote - Preventing, Finding, and Fixing Bugs On a Time Budget | Raymond Hettinger @ PyBay2018
Raymond Hettinger is one of the people I enjoy most giving tech talks. He is one of the people who know how to give very down to earth explanation about many complicated and fun topics. He also loves Python as I do, the difference being that he is a big contributor and bigger expert on Python. Definitely check out his talks on YouTube. In this post, I made some notes from his recent talk called Keynote - Preventing, Finding, and Fixing Bugs On a Time Budget | Raymond Hettinger @ PyBay2018 What testing or debugging tools have the highest payoff ...
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The Value of "Hobbies" for Tech Professionals
In this video Eli the Computer Guy talks about something I鈥檇 love more people to understand. He explains that most people expect to get money out of their first business idea. But most people don鈥檛 see beyond that initial decision. We have to consider things like: - Will people be interested in my solution/service or whatever I offer? - If I can execute my idea successfully, will I like doing it all the time, for a prolonged time? In other words, will I still love doing it next year? Wouldn鈥檛 it be much better to start something you love to ...
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How to upload thousands of contacts to Google
Today a colleague asked me for help. The boss asked him to type in about 6000 registers of Name/Phone number on to Google Contacts. I thought, "there must be a better way" (borrowed that one from Raymond Hettinger). Pre-processing First things first, I deleted all the unnecessary columns from the spreadsheet. Then it was as simple as doing an export to CSV in LibreOffice Calc. Next step, adding the right column names in the first row so that it coincides with the standard Google uses. In this case, I used: Name, Phone.
If you need a table of all the Column ...
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HOW TO PROGRAM
In this talk, Justin Searls breaks down the basic process a programmer follows while coding. Suppose we have a big, very complex problem. So much complexity scares us, we feel overwhelmed. So it's much better to not tackle all at once. Bottom-up programming Let's break the problem down into its parts by asking, what do I need for the resolution of this problem? Once you have an idea, start coding on the first one of those components. Once you work on it, you suddenly realize, Oh! This thing actually won't align with the other component I need. So you make ...
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Como censurar al Internet  con reglas simples en RouterOS
Por supuesto estoy muy en contra de la censura. Pero si entendemos como funciona la censura, tambi茅n nos podemos defender. As铆 que decid铆 aprovechar el conocimiento que adquir铆 sobre RouterOS en la certificaci贸n de Mikrotik para tratar de cortarme el servicio de Torrent con un Router Hap Lite. Como el tr谩fico de torrent mayormente ya est谩 encriptado, y el bloqueo de puertos no sirve de mucho ya que se puede hacer pasar al tr谩fico de bittorrent por puertos comunes como el 80, trataremos de prevenir al acceso de las p谩ginas de Torrent. Hice unas reglas de regex pattern matching en ...
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A quick and intuitive explanation of gradient descent
This short writeup is from Udacity's Deep Learning Nanodegree. Journey to the Bottom of the Valley Here I'll give you a little refresher on gradient descent so we can start training our network with MiniFlow. Remember that our goal is to make our network output as close as possible to the target values by minimizing the cost. You can envision the cost as a hill or mountain and we want to get to the bottom. Imagine your model parameters are represented by a ball sitting on a hill. Intuitively, we want to push the ball downhill. And that makes sense, ...
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How to Do Linear Regression using Gradient Descent
This post is based on the linear regression live coding session from Siraj Raval (Udacity). What is Linear Regression? Linear regression is a widely used method to find a predictor variable which describes an outcome variable. In simpler words, it describes the relationship of two value sets. In this example, Siraj shows how to do Linear Regression using gradient descent. Gradient descent is an iterative optimization algorithm widely used in machine learning. In simpler words, we use it to make our linear regression model as precise as possible. I won't get into details about the code, if you are interested ...
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Overview of Udacity's Deep Learning Course
Ok so here it is, the full program. I'm so excited it's hard to describe. Program Structure The Deep Learning Nanodegree Foundation program is divided into five parts covering various topics in deep learning. The first two parts are available immediately upon starting the program. The other parts are released every two weeks. Introduction The first part is an introduction to the program as well as a couple lessons covering tools you'll be using. You'll also get a chance to apply some deep learning models to do cool things like transferring the style of artwork to another image. We鈥檒l start ...
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