SEARCH KEYWORD -- Server security



  Some cases where MySQL cannot be started

After installing MySQL, when we try to start MySQL, sometimes we may not be able to start it. The reasons can be different. We share some general cases where MySQL cannot be started. Case 1: Directory or file permission issue If the permission is set wrongly in MySQL's $datadir and its sub directories or files, MySQL will not be able to read and write files normally. Error message: mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data /usr/local/mysql/bin/mysqld_safe: lin...

   MySQL,Error,Log     2013-08-15 03:32:36

  Spring – Web sockets in Java Development

Experts of java development team are sharing this article with entire java development community. The purpose behind intending this post is to explain spring – Web sockets as a concept to rest of the world. Technology: Web socket is the one of the protocol supported by web-browsers and web-servers. It provides the two-way communication between client and server. It is used in any Java application for providing the two way communication between client and server. It opens a connection betw...

   JAVA DEVELOPMENT,SPRING,JAVA TECHNOLOGY     2016-09-13 03:56:54

  When no need 3 handshakes in TCP?

Overview In the previous article titled Why TCP needs 3 handshakes simple answers were provided to the following three questions: Can application data be carried during the first handshake? Can application data be carried during the second handshake? Can application data be carried during the third handshake? Briefly, traditional TCP requires a three-way handshake to establish a connection, and during these three handshakes, only simple SYN and ACK packets are sent. From the perspective o...

   REASON,NETWORK,TCP,EXPLANATION     2024-09-29 03:19:35

  Essential skills any web developer should have

As a web developer, besides writing HTML code, there is much more to do before the site can go live. You may consider about user experience, device compatibility, security etc. To be a good web developer, you should acquire some essential skills for web development. Below we list some of them. Some of them you may be familiar with a long time ago, but definitely some of them you may not be so familiar with or even never hear about before. Interface and User Experience Be aware that browsers imp...

   Web development,User experience     2014-03-21 06:44:49

  Using Fabric to deploy web app

Many people may use FTP and rsync to synchronize codes to server, this way is fine but it may be troublesome when you need to deploy many times a day, actually there is a simple way if you can spend time on finding the fast way. We introduce Fabric today for deploying web app to remote server. Fabric is a deployment tool written with Python, the biggest feature if it is you no need to login to remote server, you can execute remote commands locally. Here is s simple deployment script written with...

   Fabric, Web deployment,SSH,Python     2012-12-08 03:16:00

  JavaScript cross domain request solution

1. What is cross domain? We may often using AJAX to request data from other domain, now we will have cross domain request issues. It's because JavaScript only allows to request data from the same domain because of security consideration. In short, same domain strategy means a piece of code can read data from the same source, the same source here means the combination of the same domain, protocol and port number. For example: URLDescriptionAllow communication? http://www.a.com/a.js http:/...

   AJAX,cross domain,security     2013-03-13 20:04:52

  Data as code

What is a good command line parser API? A good command line parser should consider below 5 aspects: Support convenient help information generation Support sub commands, for example, git has push,pull,commit sub commands. Support single character option, word option, flag option and option with parameter. Support default option, for example, if no -port is set, set it as 5037 Support usage model, for example, tar's -c and -x is mutually exclusive, they belong to different usage models. Here are...

   Command line,API     2013-08-08 22:40:36

  Chrome to block mixed content downloads in version 86

Google has announced its plan to block mixed content downloads in Chrome in February 2020 and now the day to block mixed content downloads is coming soon as we are nearing October when Chrome 86 is supposed to be released. What is mixed content downloads? According to Google, it is non-HTTPS downloads started on secure pages. For example, if you access a page called https://example.com/download, and in this page, there is a download link to http://download.example.com/something, ...

   CHROME,MIXED CONTENT DOWNLOADS     2020-09-18 21:10:53

  Redis Cluster and Common Partition Techniques in Distributed Cache

In this post, I will discuss a few common partition techniques in distributed cache. Especially, I will elaborate on my understanding on the use of Redis Cluster. Please understand that at the time of writing, the latest version of Redis is 4.0.10. Many articles on the same topic have a different idea from this post. This is mainly because, those articles are probably outdated. In particular, they may refer to the Redis Cluster implementation in Redis 3. Redis Cluster has been improved...

   REDIS,DISTRIBUTED CACHE,CLOUD COMPUTING     2019-01-17 08:10:37

  Using Java keytool programmatically

Java provides a command line tool to access and operate different keystore which store keys and certificates. This tool is named keytool and is located at \bin.  On command line, you can issue below command to generate a keystore named mytest.jks which contains a private key and certificate chain. keytool -genkeypair -alias mykey -keyalg RSA -sigalg SHA256withRSA -dname CN=Java -storetype JKS -keypass password -keystore mytest.jks -storepass password Sometimes, in testing purpose, w...

   JAVA,KEYTOOL     2016-01-09 06:28:07