• Remote connection to Linux


    Catalog 1. Why to connect Linux remotely 2. Necessary knowledge of remote connection 2.1 IP address > location of server 2.2 LAN 2.3 external network Ip 3. Virtual machine network configuration 3.1NAT mode 3.2 bridge mode 3.3 host only mode 4. Concept of port 5. Concept of agreement 1. Why to connect Linux remotely In […]

  • Open Android Application “black domain” under mac


    Install ADB brew cask install android-platform-tools After installation, connect the computer to the mobile phone, turn on the USB debugging mode, and note that the mobile phone needs to turn on the developer mode Open the mobile phone information, click the version information, and click until you are prompted to open the developer mode For […]

  • Summary of PHP in redis sentinel mode


    In the near future, the cache of the company’s projects wants to be migrated from Memcache to redis. The redis usage mode configured for operation and maintenance is sentinel (sentinel mode), which has not been used before. Please record here. Briefly introduce redis sentinel:Redis sentinel is a monitoring management, notification and instance failure backup service […]

  • Kafka source resolution 1: cluster cluster information


    Summary During the operation of kafkaproducer, the cluster meta information is needed, which is stored in cluster Node, topicpartition and partitioninfo Cluster meta information is composed of three types of objectsNode, TopicPartition, PartitionInfo Node source code node represents a node in the cluster Topicpartition source topicpartition represents a partition of topic Partitioninfo source code partitioninfo […]

  • Redis learning note 2 – cache, cluster, consistency, etc


    Cache retirement strategy In order to ensure high performance, the cache is stored in memory. When the memory is full, we need to eliminate the old data through appropriate strategies to make room for new data. The data elimination strategies typically include FIFO (first in, first out, elimination of the oldest data), LRU (elimination of […]

  • One text to understand visitor mode


    Basic introduction What is the visitor model? Visitor pattern pattern is a behavioral design pattern, which provides a way to operate on each element of an object structure. It enables us to define new operations on elements without changing the element structure. If the data structure of the system is relatively stable, but its operation […]

  • Recovery of NOARCHIVELOG and archive modes under RMAN


    Resume atNOARCHIVELOGDatabase of patterns When the database is inNOARCHIVELOGIn mode, if there is a media failure, any operations on the database after the last backup will be lost. adoptRMANWhen performing a recovery, only therestoreCommand to repair the database file to the correct location, and then you can open the database. In other words, for theNOARCHIVELOGThe […]

  • vim


    Catalog Vim and programmer 2. What is VIM? 3. Use of VI / VIM 3.1 command mode: 4. Input mode 5. Bottom line command mode 5.1 VIM working mode 6.vim button Vim and programmer All UNIX like systems will have built-in VI document editors, while other document editors may not exist. But now we use […]

  • IOS13 adaptation


    1. private KVC [self setValue: basetabbar forkey: @ “tabbar”]; // normal [﹐ textfield setValue: [uicolor redcolor] forkeypath: @ “﹐ placeholderlabel. Textcolor”]; // / crash [‘textfield setValue: [UIFont systemfontofsize: 14] forkeypath: @ “‘u placeholderlabel. Font ‘]; // / crash _Textfield. Attributedplaceholder = [[nsattributedstring alloc] initwithstring: @ “name” attributes: @ {nsfontattributename: [UIFont systemfontofsize: 14], nsforegroundcolorattributename: [uicolor redcolor]}]; […]

  • For performance, PHP excel extension xlswriter 1.3.3 is released!


    Xlswriter is a PHP C extension that can be used to read data in Excel 2007 + xlsx files, insert multiple worksheets, and write text, numbers, formulas, dates, charts, pictures, and hyperlinks. It has the following features: First, write 100% compatible excel xlsx file Complete excel format merge cell Define sheet name Filter Chart Data […]

  • Kafka operation of spring boot series


    Kafka operation of spring boot series Kafka introduction Apache Kafka ® is a distributed streaming platform. There are three key functions: Publish and subscribe record flows, similar to message queuing or enterprise messaging systems. Stores the record stream in a fault-tolerant, persistent manner. Process flow when records occur. Kafka is commonly used in two broad […]

  • IOS remote notification method trigger


    IOS remote notification trigger 1、 System under IOS 10 It is a method. There is no way to distinguish the specific situation of receiving notification and clicking notification. You can use uiapplicationstatebackground to judge the situation of the front and back office // This method will be invoked even if the application was launched or […]