SEARCH KEYWORD -- System

  Check whether a remote server port is open on Linux

As a system administrator or network engineer or application developer, there is a need to check whether a port on remote server is open so that you can tell whether the service under check is running or not. In this post, we would cover a few methods to check whether a remote server port is open or not on Linux. telnet telnet is the most frequently used command on both Windows and Linux to check port. The simple usage for this command is  telnet [host] [port] When the port is open, the o...

   LINUX,TELNET,PORT,NC,NMAP     2017-12-23 11:45:20

  Does My Online Business Need Log Aggregation?

Logs crop up all over the place. They are generated by everything from web servers and databases to the firewalls which protect them from breaches. Because logs accumulate in large volumes from all of these different sources, log aggregation is an important process which works to organize and impose order over otherwise disparate log files. That sounds good, but should your online business be eager to jump on the log aggregation bandwagon? Here is a look at the main benefits and considerations t...

   SOFTWARE DESIGN,LOG AGGREGATION     2021-10-12 21:44:39

  Basic Mistakes Developers Make When Creating APIs

Today, there are many tools that developers can use to create an API, meaning that some of them can come up with an API within a matter of minutes. However, there is a vast difference between just creating an API and building one that meets all your expectations, is reliable and secure. Some developers create APIs that work well but forget some basic things that, within no time, bring a lot of issues to the API users. In this article, we are going to talk about the basic mistakes that developers...

   API,API DESIGN,RESTFUL API     2020-08-19 07:54:03

  When a CA becomes untrustable

Information security has become a vital part of people's life, especially for those people who spend much time online. Tons of data are being transmitted over the internet every second. These data include user ids, passwords, credit card information etc and some of them are sensitive information which needs secure way to transmit. Hence different protocols have been developed including SSL/TLS to encrypt data transmitted over the internet. The core of these security protocols is the certifi...

   APPLE,SECURITY,GOOGLE,MOZILLA,NEWS,WOSIGN     2016-10-01 23:03:44

  Why exception would be thrown when deleting element while looping through HashMap in Java

HashMap and other Collection types are frequently used in Java application programming. This post will explain why exception would be thrown when deleting element with Map.remove() while looping through a Map using Iterator. This issue would also occur to other Collection types such as Set, List. Below is a sample code snippet demonstrating the exception thrown. Map<String,String> map = Collections.synchronizedMap(new TreeMap<String,String>()); map.put("key1","value1"); map.put("ke...

   JAVA,HASHMAP,CONCURRENTMODIFICATIONEXCEPTION     2018-06-30 12:49:09

  New Linux kernel fixes power-saving issues

Greg Kroah-Hartman has released long-term kernel 3.0.20 and stable kernel 3.2.5. Both contain just a single bug fix that allows PCIe power-saving technology ASPM (Active State Power Management) to be used on systems with a BIOS that activates ASPM on some components, but states in the FADT (Fixed ACPI Description Table) consulted by Linux that ASPM is not supported. According to Matthew Garrett, who developed the patch, the change can reduce the power consumption of a Thinkpad X220 by 5&nbs...

   Linux kernel,Power saving,Fix     2012-02-08 10:10:36

  Three things you should never put in your database

As I've said in a few talks, the best way to improve your systems is by first not doing "dumb things". I don't mean you or your development staff is "dumb", it's easy to overlook the implications of these types of decisions and not realize how bad they are for maintainability let alone scaling. As a consultant I see this stuff all of the time and I have yet to ever see it work out well for anyone. Images, files, and binary data Your database supports BLOBs so it must be a good idea to shove ...

   Database,BLOB,Log,Image     2012-05-02 04:44:25

  The concept of Iterative Model in a Software Development Life Cycle (SDLC)

The iterative model implemented in any Software Development Life Cycle is all about an initial, simplified implementation which may or may not gain more complexity in future. Furthermore, it is can even be called as a broader feature set until and unless the final system is accomplished. Now while discussing the model, chances are there that he concept of incremental development will also often be used liberally and interchangeably. This means incremental alterations made during the design and i...

   SOFTWARE DEVELOPMENT,SDLC,ITERATIVE MODEL,SOFTWARE DEVELOPMENT LIFE CYCLE     2017-09-11 06:02:39

  Want to be a software engineer? Go to university

This editorial was originally submitted to the Sydney Morning Herald in response to an editorial proclaiming that people wanting to become software engineers should not attend university and instead learn a current popular programming language.   Over the past few years I’ve developed software for large corporations, started the Vodafail campaign, co-founded Mijura and represented Australia in the global Robocup (humanoid robotic soccer) competition. I graduated from University...

   Software engineer,University,Systematic study,Research     2011-12-07 08:48:54

  9 Ways to Create Thread Pools with Java Executors

In Java, the Executors class provides a variety of static factory methods to create different types of thread pools. When learning about thread pools, the Executors class is indispensable. Mastering its usage, principles, and scenarios will enable you to apply it smoothly in actual project development. Here are some commonly used methods, which I will explain one by one: newCachedThreadPool(): Creates a cached thread pool. If a thread has not been used for 60 seconds, it will be terminated and ...

   TUTORIAL,JAVA THREAD     2024-07-19 23:07:09

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