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Tags: Linux notesEight weeks two sessions (March 27)10.28 Rsync Tools Introduction10.29/10.30 rsync Common Options10.31 rsync sync via sshThe native a directory to B directory at a small time just added a file. Either find the file, or cover the B, and read and write a waste of time. You can synchronize the updated file with Rsync. A machine to B machine can also be synchronized.This machine rsyncA machine to B machine10.29 rsync Common Options--DELETE:A Machine 123 Synchronization B machine 123

Ping does not pass 192.168.100.1 and 192.168.100.100To view the gateway, run the following command.No gatewaysSet the gateway and run the following command.Can ping throughSet up DNS. 119.29.29.29 is a public DNS.Can ping the DNS, you can ping the outside network.Only 1 IPCannot ping pass.A machine equivalent to a router, B machine equivalent to a router phone, computer, can now be networked.10.18 iptables NAT Table ApplicationWindows cannot ping through 192.168.100.100Each operation needs to b

command. Clear the rules, save no use.Restart the service and load it back.Zeroing the calculatorI wrote a monitoring script and found that IP had a field that dropped the IP. Review the rules if the number of packets does not exceed 100. can be solved by sealing off. The number through the first column. Recalculate after 30 minutes.After the data came, said not to say, directly kicked off.After the data came, say, can't come in.The usage of-I. -I is inserted, metaphorically queued, inserted to

8sdafasdf ' ++echo8sdafasdf++sed ' s/[0-9]//g ' +n1=sdafasdf+ ' [' -n sdafasdf '] ' +echo ' Pleaseinputanumber. ' Pleaseinputanumber.+exit1[[email protected]shell]#sh-xcase.sh+read-p ' Pleaseinputa number: ' nPleaseinputanumber:123 # #输入一个大于100的数字 + ' [' -z123 ' ++echo123++sed ' s/[0-9]//g ' +n1=+ ' [' -n ' ' ' + ' [' 123-lt60 '] ' + ' [' 123-ge60 '] ' + ' [ ' 123-lt80 ' ' + ' [' 123-ge80 '] ' + ' [' 123-lt 90 ' + ' [' 123-ge90 '] ' + ' [' 123-le100 '] ' + tag=0+case $tag in+echo ' thenumberra

exitingVariable PS1 definition prompt, modified under/ETC/BASHRC[[email protected] ~]# echo $PS 1[\[email protected]\h \w]\$ # #如果将W换成w, then the path will become an absolute path [[email protected] ~]#PS1 = ' [\[email protected]\h \w]\$ ' [[email protected] ~] #cd/tmp/d6z/[[email protected]/tmp/d6z] #PS1 = ' [\[email Protected]\h \w]\$ ' [[email protected] d6z]#can be set with color displayps1= ' \[\033[01;32m\]\[email protected]\h\[\033[00m\]:\[\033[01;36m\]\w\[\033[00m\]\$ '2018-1-11 5 weeks

10.6 Monitoring IO PerformanceIostat and SAR belong to the same installation package; view disk usage;Iotop command, install #yum install-y iotop10.7 Free CommandFree to view memory usage10.8 PS CommandPS static view process status, top is the dynamic display process status;PS aux and ps-elf view process effect is similar;10.9 Viewing network status-l,listen monitoring;LNUTP, view only TCP and UDP;Established the number of concurrent connections, generally less than 1000, more than two thousand

Tags: Linux notesSeven weeks two sessions (March 20)10.6 Monitoring IO Performance10.7 Free Command10.8 PS Command10.9 Viewing network status10.10 Linux under Grab BagExtended TCP three-time handshake four times wave http://www.doc88.com/p-9913773324388.htmlTshark several usages: http://www.aminglinux.com/bbs/thread-995-1-1.htmlInstalling the package Sysstat will install the Iostat. And SAR are the same package.%util is the percentage of waiting IO. The hard disk can affect the performance of th

10.11 Linux Network relatedIfconfig-a can display the disabled or down network card;Start the network card #ifup ens33; Disable the network card #ifdown Ens33;Nic configuration file/etc/sysconfig/network-script/ifcfg-ens33Copy Create virtual network adapter profile, #cd /etc/sysconfig/network-script/#cp Ifcfg-ens33 ifcfg-ens33\:0#vi!$10.12 Firewalld and NetFilterGetenforce View firewall status;10.13 NETFILTER5 Table 5 Chain IntroductionView NetFilter instructions, #man netfilter;10.14 iptables S

connect the MONGO from the library. (2) When deleting the MONGO table in hive, remove the jar package configuration in Hive-site.xml, and after disconnecting the Hive table from the MONGO, be careful! If you keep driving and drop directly, the table data in the MONGO will be drop. The most important thing is that your ops should do the right configuration of MongoDB in advance and give read-only permission to prevent misoperation. (3) in general, as long as the configuration is good, this plu

This class, this semester we have only one of the three departments of this course, many many many students say why you have to choose this course. Parents also say, why don't you come with the crowd. Someone asked me before, whether regrets chose such a class, I said, regret. This course, which requires self-study and my student work, almost fills my own leisurely junior. Said regret that Thursday, I still for Lou big exam struggle, scratching the scalp, bite broken fingers, restless. Now, this

Constructor As a result, I was ridiculed by my friends. Of course, I did not accept it and I argued with it. A friend suggested that I run it for a moment. I thought it was the same. The facts showed everything. So I created a project, copied, pasted, and ran it. Then I was dumpfounded. The result turned out to be: Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->Subclass Constructor Impossible! Why didn't the base class constructor run? Search

take the net Webshell data.asp?action=backupdata network database backup default path 36. Tools: Website Hunter webshell keyword: inurl:Went.asp suffix: manage/login.asp weak password: ' or ' = ' or '51, the invasion of the press release system Key words: Leichinews remove leichinews behind. Hit: admin/uploadpic.asp?actiontype=modpicname=xuanran.asp then upload the horse ..... Access Uppic anran.asp landing horse.52. First, through GOOGLE search to find a large number of injection point keyword

Tags: LinuxSeven weeks Five sessions (March 23)10.19 iptables Regular backup and recovery10.20 Firewalld 9 Zone10.21 Firewalld About zone operation10.22 Firewalld about service operations10.19 iptables Regular backup and recoveryBackup, command as followsIptables rules can be backed up to other files, and the file name can be taken by itself.Only the rules for NAT.There are no rules in this tableBack up the rules just nowIf you want to restart, load, you need to put in the configuration file, to

the data has been mistakenly deleted, the first thing to do is to unload the partition of the deleted data, if the data of the root partition is mistakenly deleted, you need to enter the system into single user mode, and the root partition is mounted in read-only mode. Since the file is deleted, only the sector pointer in the Inode node of the file is zeroed out, the actual file is also stored on disk, and if the disk continues to mount in read-write mode, the data blocks of these deleted file

While loopThe process is as followsWhile condition:code blockKey words1 break is used to end the sequence, the following code is not executing2 Continue is used to jump out of this sequentialExample output 1-100 or less all positive integersThe code is as followsS1 = 1While True:Print (S1)if S1 = = 100:BreakS1 + = 1Example of cumulative sum of output 1-100Analysis, 1 now implements a positive integer of output 1-100B1 = 0S1 = 1While True:Print (S1)B1 = B1 + S1if S1 = = 100:BreakS1 + = 1Print (B1

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Write a function that meets the following requirements:A) Calculates the result of printing all parameters and multiplying the cardinality (base=3)b) If the last argument in the parameter is (base=5), the cardinality is set to 5, and the cardinality does not participate in the sum calculation.#-*-Coding Utf-8-*-def results (*i): sum=0 for J in I: sum + = J if I[len (i) -1]==5: c10/>sum= (sum-5) sum*=5 else: sum*=3 return Sumprint (results (1,2,3,4,5)) Little Turtle Python cou

single line, it is not equivalent to a C or C + + inline function, which is designed to call small functions without consuming stack memory to increase operational efficiency.Example:#!/usr/bin/python#-*-Coding:utf-8-*-# Writable Function Descriptionsum = lambda arg1, arg2:arg1 + arg2;# Call the SUM functionPrint "added value is:", SUM (10, 20)Print "added value is:", SUM (20, 20)Built-in functions:Common functions:ABS ()Max ()Min ()Len ()Divmod ()POW ()Round ()Callable ()Type ()Isinstance ()CM

above, the data is not accurate.If you want to avoid this situation, just use get and CAS, such as:#!/usr/bin/env python#-*-Coding:utf-8-*-#Author: Haifeng DiImport MemcacheMC = Memcache. Client ([' 192.168.10.128:12000 '], debug=true)v = mc.gets (' Product_count ')Print (v)#如果有人在gets之后和cas之前修改了product_count, the following setting will fail to throw an exception to avoid output of abnormal dataV1 = Mc.cas (' Product_count ', "899")Print (v1)#结果:899TrueIn essence, each time the get is executed,

while loop.The break statement terminates the Loop statement, that is, the loop condition does not have a false condition, or the sequence is not fully recursive, and the loop statement is stopped.The break statement is used in the while and for loops.If you use a nested loop, the break statement stops executing the deepest loop and starts executing the next line of code.The Python continue statement jumps out of the loop, and break jumps out of the loop.The continue statement is used to tell P