首先，我们应该清楚的是，日志文件不仅可以帮助我们追踪入侵者的来源并找到其攻击路径，而且在正常的操作和维护中，日志还可以反映出许多安全攻击。
一个简单易用的Web日志分析工具可以大大提高效率。当前，行业中有许多日志分析工具。今天，我们推荐十种易于使用的Web日志安全性分析工具。

First of all, we should be clear that log files not only help us trace the origin of an intruder and find their attack path — in normal operations and maintenance, logs can also reveal many security attacks.

A simple, easy-to-use web log analysis tool can greatly improve efficiency. There are many log analysis tools on the market today. Here we recommend ten easy-to-use web log security analysis tools.

1、查看进程占用带宽情况-Nethogs

Nethogs 是一个终端下的网络流量监控工具可以直观的显示每个进程占用的带宽。
下载：http://sourceforge.net/projects/nethogs/files/nethogs/0.8/nethogs-0.8.0.tar.gz/download

yum -y install libpcap-devel ncurses-devel
tar zxvf nethogs-0.8.0.tar.gz
cd nethogs
make && make install
nethogs eth0

1. Check which processes are eating bandwidth - Nethogs

Nethogs is a terminal-based network traffic monitoring tool that shows the bandwidth each process is using, in a visual way.
Download: http://sourceforge.net/projects/nethogs/files/nethogs/0.8/nethogs-0.8.0.tar.gz/download

yum -y install libpcap-devel ncurses-devel
tar zxvf nethogs-0.8.0.tar.gz
cd nethogs
make && make install
nethogs eth0

• HAProxy是什么

  HAProxy 是一个免费的负载均衡软件，可以运行于大部分主流的 Linux 操作系统上。

  HAProxy 提供了L4（TCP）和L7（HTTP）两种负载均衡能力，具备丰富的功能。

  HAProxy 的社区非常活跃，版本更新快速（最新稳定版1.7.2于2017/01/13推出）。最关键的是，HAProxy 具备媲美商用负载均衡器的性能和稳定性。

  因为 HAProxy 的上述优点，它当前不仅仅是免费负载均衡软件的首选，更几乎成为了唯一选择。

• What is HAProxy

  HAProxy is a free load balancing software that can run on most mainstream Linux operating systems.

  HAProxy provides both L4 (TCP) and L7 (HTTP) load balancing capabilities, with a rich feature set.

  HAProxy’s community is very active and releases come quickly (the latest stable version 1.7.2 was released on 2017/01/13). Most importantly, HAProxy offers performance and stability comparable to commercial load balancers.

  Because of these advantages, HAProxy is not only the first choice among free load balancing software, but has almost become the only choice.

一直追求完美的系统，断断续续用laravel和Yii做开发，最终选择了laravel8来开发一套管理系统

laravel-erik-admin

• 第一阶段

  版本预计1.0，主要是基础的管理系统，包含管理员、角色、权限等基础功能，后续会提供后台页面

Always chasing the perfect system, I developed on and off with laravel and Yii, and finally chose laravel8 to build a management system

laravel-erik-admin

• Phase 1

  Version expected to be 1.0, mainly a basic management system with admin, roles, permissions and other basic features; backend pages will be provided later

• yar

  Yar(Yet Another RPC framework)是一个轻量级支持并行调用的PHP RPC框架
  学习地址 https://www.laruence.com/2020/03/16/5578.html
  

• yac

  无锁共享内存Cache
  
  学习地址 https://www.laruence.com/2013/03/18/2846.html
  

• yar

  Yar(Yet Another RPC framework) is a lightweight PHP RPC framework that supports parallel calls
  Learning resource https://www.laruence.com/2020/03/16/5578.html
  

• yac

  Lock-free shared memory Cache
  
  Learning resource https://www.laruence.com/2013/03/18/2846.html
  

最近陆陆续续发现2019年左右，在个人博客写的文章被抄袭搬运至csdn和百度文库。

在csdn上举报了一部分，还有一部分由于是发表在个人博客，后转发至csdn时间较晚（抄袭者估计爬虫我博客），无法举报成功，大家以后尽量发带图文或者先在其他平台发布文章后，再在自己博客发表，以防抄袭者不劳而获的抄袭。

Recently I’ve been discovering, one after another, that articles I wrote on my personal blog around 2019 have been plagiarized and reposted to CSDN and Baidu Wenku.

I reported a portion of them on CSDN, but for the rest — since they were published on my personal blog first and only forwarded to CSDN much later (the plagiarists were probably scraping my blog) — the reports couldn’t succeed. From now on, everyone should try to publish articles with images, or publish them on other platforms first and then post them on their own blog, to prevent plagiarists from getting something for nothing.

基础数据结构

• 字符串（string）

  • 字符串、整数、浮点数
  • 对整个字符串或者字符串的其中一部分执行操作，对整数和浮点数执行自增或自减操作

• 哈希列表（hash）

  • 包含键值对的无序散列表
  • 添加、获取、移除单个键值对，获取所有键值对，检查某个键是否存在

Basic data structures

• String

  • Strings, integers, floating-point numbers
  • Operate on an entire string or part of one; increment or decrement integers and floats

• Hash

  • An unordered hash table of key-value pairs
  • Add, get and remove individual key-value pairs, get all key-value pairs, check whether a given key exists

一.文件和目录

1.
cd命令，用于切换当前目录，它的参数是要切换到的目录的路径，可以是绝对路径，也可以是相对路径。

  cd /home    进入 '/ home' 目录
  cd ..            返回上一级目录 
  cd ../..         返回上两级目录 
  cd               进入个人的主目录 
  cd ~user1   进入个人的主目录 
  cd -             返回上次所在的目录

1. Files and directories

1.
The cd command is used to switch the current directory. Its argument is the path of the directory to switch to, and it can be either an absolute path or a relative path.

  cd /home    enter the '/home' directory
  cd ..            go back to the previous directory level 
  cd ../..         go back up two directory levels 
  cd               enter the personal home directory 
  cd ~user1   enter the personal home directory 
  cd -             go back to the directory you were in last

Linux不像windows有那么显眼的回收站，不是简单的还原就可以了。 linux删除文件还原可以分为两种情况，一种是删除以后在进程存在删除信息，一种是删除以后进程都找不到，只有借助于工具还原，这里分别检查介绍下。

一、误删除文件进程还在的情况。

这种一般是有活动的进程存在持续标准输入或输出，到时文件被删除后，进程PID还是存在。这也就是有些服务器删除一些文件但是磁盘不释放的原因。比如当前举例说明： 通过一个shell终端对一个测试文件做cat追加操作：

Linux does not have a recycle bin as conspicuous as Windows, so you cannot simply restore things. Restoring deleted files on Linux can be divided into two cases: one where after deletion there is still process information holding the file, and one where after deletion no process can be found at all and you have to rely on tools to restore it. Let’s look at each of them in turn.

1. The case where the process that accidentally deleted the file is still running.

This is usually a case where an active process keeps standard input or output open, so even after the file is deleted the process PID still exists. This is also the reason why deleting some files on a server does not free up disk space. For example, here is a demonstration: using a shell terminal to append to a test file with cat:

绝大多数MySQL性能指标可以通过以下两种方式获取：

（1）mysqladmin

使用mysqladmin extended-status命令获得的MySQL的性能指标，默认为累计值。如果想了解当前状态，需要进行差值计算；加上参数 —relative(-r)，就可以看到各个指标的差值，配合参数—sleep(-i)就可以指定刷新的频率。

The vast majority of MySQL performance metrics can be obtained in the following two ways:

(1) mysqladmin

The MySQL performance metrics obtained with the mysqladmin extended-status command are cumulative values by default. If you want to know the current state, you need to compute the difference; adding the parameter —relative(-r) lets you see the delta of each metric, and with the parameter —sleep(-i) you can specify the refresh frequency.