Shell

Dbcn= "mysql-h172.16.1.194-uroot-p123456";d b=dsp_ad_center;ii=0;ct= ' $DBCN-n-E "select COUNT (1) from Information_sch Ema. TABLES as t WHERE t.table_schema = ' $db ' and t.table_type = ' BASE TABLE '; "'; mkdir-p/chenenhui/$dbwhile true;doif

There are two recent problems with insufficient database connections, usually reserved for some session increase, but in some special cases such as connection storm, if there is no rate limit in the monitoring, a huge impact on the database may

SED is designed to handle all editing tasks at once, particularly efficiently, saving users a lot of time, and SED is suitable for the following three scenarios:1. Edit files that are too large relative to the interactive text editor;2, editing

At the user's point of view, there are two types of shells:log-in Shell:Log in normally via a clientSu-username or Su-l USERNAMENon-logon shell:Su USERNAMECommand window open under graphical terminalShell scripts that are executed automaticallyBash

ShellFirst, the conceptShell commonly known as shell (used to distinguish from the kernel), refers to the "provide user interface" software (command parser), will receive users ' commands, parse and invoke the corresponding application.Ii.

1. Enter the HBase command line./hbase Shell2. Display the list of tables in HBase3. Create a user table with info, data two column familiesCreate ' user ', ' info1 ', ' data1 'Create ' user ', {NAME = ' info ', VERSIONS = ' 3 '}4. Insert the

I. OverviewThe read command receives input from a standard input (keyboard), or other file descriptor. After the input is received, the Read command puts the data into a standard variable.Ii. examples of use (here are just a few common options)1.

Convert the 0024.b20b.693f address into a 00:24:b2:0b:69:3f1. Dot-delimited[Email protected] ~]# echo "0024.b20b.693f" | Sed-r ' s/\b (..) (..) \b/\1:\2/g;s/\./:/g '00:24:b2:0b:69:3f2. If the colon is separated, convert the 0024:b20b:693f to 00:24:b2

On the BBS saw the Shell 13 asked the post, because the comparison is far away, afraid later can not find, put the notes over,Original address:Shell 13 AskHttp://bbs.chinaunix.net/thread-2033675-1-1.htmlPost the notes I made:, why a Shell user

All files have 3 time information, saved in the file system Atime (Access times)Is the last time the file was read or the time the file was executed Mtime (Modified times)Is the last time the file was written (it was changed when the file was

in this example, the master node has the host name of Master, and the hostname of the slave node is slave1,slave2,slave3, the user name is Hadoop, and the zookeeper version used is zookeeper3.4.5. Run the following script under ROOT to achieve a

Top of the Bash shell Command and monitor　　The last time we talked about the PS command, although the PS command is useful in collecting process information running on the system, but there are shortcomings, PS command can only display information

1-echo ' Date ' +%y-%m-%d%h:%m:%s "'2014-11-13 15:06:262-echo ' Date ' +%y-%m-%d%h:%m:%s "'14-11-13 15:06:51Note: "+%y-%m-%d%h:%m:%s" caseThe given format controls the output, and the sequence is interpreted as follows:Percent of a text%%a of the

One, for loop[email protected] shell]# cat for.sh#!/bin/bashFor i in ' seq 1 10 '; Doecho "$i"DoneWith this script you can see the basic structure of the For loop:The condition of the for variable name in the loop; do Commanddone[Email protected]

The previous period of time to maintain the server, need to install the LNMP environment, so I tidied up a bit, as a script, recorded.#!/bin/sh#copyright (c)  2010-2015 redapple  ([email protected]) #install  lnmp # version 0.1.1#date 20140813#------

Format: "\033[display mode; front color; background color m string \033[0m"\033: Starting an escape sequence[: Start Color definitionThere are several ways to display the method:0 Terminal default settings1               高亮显示4               使用下划线5   

1. CycleThe shell loops and executes a program continuously until the condition is met. Loops are divided into 4 types, while loops, until loops, for fixed processing, for numeric processing.2. While loopThe while loop is executed until the

Occurs when a service command is executedShell-init:error Retrieving current Directory:getcwd:cannot access parent directories:no such file or directoryChdir:error Retrieving current Directory:getcwd:cannot access parent directories:no such file or

inadvertently see the router inside there is a dynamic domain name, and later on-line a check that it is possible to establish a personal website, and then allow other users on the network to access their own servers, such as their own establishment

Shell script to replace the tomcat cluster war package Run the command to log on to the server without ssh. The configuration file does not change much to overwrite the previous configuration. Profile configuration file Bak =/home/wsm/bakWebapps