How to do Troubleshooting

How to do Troubleshooting

IT Technology is a technology

All sciences and technology belong to Logic

All of us have logic think ability.

Differet Roles of Human Beings in IT

Researcher    ---  Developer ---  Administrator --- User

Troubleshooting is the top ability of an administrator!

My view about Software Industry:

Open Source is more and more strong;

Open Source is better in serer side than in desktop side;

More and more administrator jobs are required;

GUI  && CML

Command Line Interface

STDIN                      ----       Program   ----    STDOUT

Configuration Files        ----       Software  ----    Log files

Environment Variables     ----       Process ----     STDERR

software talks to software

Program1        Protocol           Program2

Software1    ------------------    Software2

Process1        tcp/ip             Process2

TCP/IP             &&           IPC

 

                              SHM:Shared Memory

TCP   UDP                      MSG:Message Queue

  IP                          SEM:Semaphore

  

  

  

  

  Configuration files:

  Text file only

  

  Text file -- Binary file

  

  Binary file

  

  

  

  Environment Variables:环境变量表，在内存中有一个地址块，存放环境变量表。

  

  Every process can modify /add/delete its environment variables

  

  Child process can inherit the variables from parent process

  

  Parent process must "export" the Environment Variables to let child process to inherit them

   

  Child process cannot modify the Environment Variables of parent process

  

  eg：

  ORACLE 

  .bash_profile

  

  

  

  Log Files:

  

  Text file only.

  

  Binary file

  

  $ cat /dev/null >mylogfile    清空再操作

  

  $ tail -f mylogfile   查看日志尾部信息

  

  

  从配置文件中查找日志文件的位置

  

  cat  error_log |grep WARN

  

  

  How to Master a Software?

  

  know its architecture

  know where we can get its configuration files

  know where we can get its log files

  know how to modify its configuration files

  know how to read and analyze its logfiles

  

  

  

The process of Doing Trouble Shoot

step 1,Read the error message on the screen:STDOUT/STDERR

step 2,know where to get the log files

step 3,know where to get the corresponding blocks in the log files

step 4,use your HEAD to think

step 5,Get an Conclusion,and try it

step 6,Repeat step 4 and step 5;