linux networking interview questions and answers

Classic Linux kernel interview questions 1) What kernel locks does Linux have? 2) What is the meaning of the user mode and Kernel Mode in Linux? 3) How to Apply for a large kernel memory? 4) What are the main methods for inter-process communication? 5) What are the function

. Synchronize the data between the main library and the library, and then repeat the action again13. Use a single command to turn off all services except SSHD, Crond, network, Rsyslog services (no power-on automatic)Method One:[[Email protected]~]# for name in ' Chkconfig–list|grep 3:on|awk ' {print '} ' |grep-ev "sshd|crond|rsyslog|network" ';d och Kconfig $name Off;done[Email protected]~]# chkconfig–list|grep 3:onCrond 0:off 1:off 2:on 3:on 4:on 5:on 6:offNetwork 0:off 1:off 2:on 3:on 4:on 5:o

, the connection file is unavailable. 11. What commands are available to view the file content? What are their respective features? More: You can only view the last part of the file. It is inconvenient to flip the page. Less: it is easy to flip pages and frequently used to view large file content. Cat: The content is relatively small. Cat-n lists the row numbers by the way. 12. What are the common formats of compressed packages in Linux? What are th

data sent by the listener does not need to decrypt to see the content. How do you virtualize a Linux physical machine? Tell me some weird linux commands. Explains how HTTPS works. http://blog.csdn.net/sean_cd/article/details/6966130How HTTPS works Do you know Tor browser? Explain how it works. How do I trigger a forced system check the next time I start the machine? What backup technology do

Linux interview questions required for O M 1. What is GPL, GNU, and free software? GPL: (General Public License): An authorization. Anyone has the right to obtain, modify, and re-release free software. GNU: (Plan): it aims to create a completely free and open operating system. Free Software: software that can be freely used, copied, researched, modified, and dis

Linux Shell script interview 25 questions Q: What is a 1 Shell script and is it necessary? A: A Shell script is a text file that contains one or more commands. As a system administrator, we often need to use multiple commands to complete a task. We can add all these commands in a text file (Shell script) to complete these daily tasks.Q: 2 What is the default logo

://www.baidu.com/s?wd=test on the specified server 61.135.169.121, and the time-out for the access is 20 seconds: Curl–connect-timeout Http://61.135.169.121/s?wd=test 9. With the netstat command with other shell commands, according to the source IP statistics all the established status links to 80 ports, the output is similar (the first column number of connections, the second column IP): [Email protected]~]# Netstat-an|grep establishedTCP 0 139.224.199.85:22 101.47.33.86:

Interview Questions for Linux System Engineers:1. view the maximum value of a single shared memory segment in Linux (command)IPCS-mIPCS-2. What command is used to query the server port of the specified IP address?The NMAP and nbtscan commands should be used to scan the question.3. What commands are used in crontab to d

A company's Linux platform C programmer asked a question during the interview-Linux general technology-Linux programming and kernel information. The following is a detailed description. 1. How many lines of project code do you have? 2. What is the role of the volatile keyword in C? 3. How to Write a daemon process 4

];thenshell=$ (cat/etc/passwd |grep "$result" |cut-d:-f7) echo "$shell" |grep "sh$" shell_ result=$?if[ $shell _result-eq0]; thenecho "Ausercan logsystem. " else echo "User$1nologinsystem." fielse echonbSP; " useridlessthan500. " fi10, write a script to complete the following tasks: (1) In order to copy each direct file or subdirectory under the/var/log directory to the/TMP/TEST1-TESTN directory, (2) to copy the directory, use the CP-R command; (3) Use the CP command when copying files, (4)

as 2:32 below, indicates how long the system has been running since the last start.[[email protected] DOWNLOAD] #uptime02:05:22 up 2:32, 2 users, Load average:0.00, 0.00, 0.0014. How to add route in Linux systemHost routingRoute add-host 192.168.197.100 Dev eth0Gateway RoutingRoute add default GW 192.168.197.1Network routingRoute ad-net 192.168.1.0 netmask 255.255.255.0 deveth1Route ad-net 192.168.1.0 netmask 255.255.255.0 gw192.168.197.115. The cont

"the echo command test!." This line of text!echo "The echo command test!" >a.shThis will output "the echo command test!" in the a.sh file. This line of text!The general format of the command is: Echo [-n] string where option n means that the output text is not wrapped, the string can be quoted, or it can be unquoted.When you output a quoted string with the Echo command, the string is output as it is;When you output an unquoted string with the echo command, each word in the string is output as a

most common and most effective of this attack is UDP flood attack, encountered this attack, most of the time is helpless, need to use the computer room hardware security facilities to defend. So how do you judge this attack? Very direct performance is your website can not open, bandwidth running slow, server login is not on, if you can board the server, you could use TCPDUMP-NN grab packet will find a lot of UDP packets, and very frequent. Using the Iptables tool to seal the IP is useless. Traf

Linux O M engineer interview question 1. file file11 is available. use shell to query the row number awk amp; lsquo; {if ($0 ~ /^ $/) PrintNR} amp; rsquo; fileorgrep-n ^ $ file | awk amp; lsquo; BEGIN {FS :}{ print $1} amp; linux O M engineer interview question 1. file file11 is available. use shell to query the

I. Fill in blank questions:1. Access the device as a file in Linux.2. Read the file system to be loaded from the file/etc/fstab during Linux kernel boot.3. Each file in the Linux File System is identified by an I node.4. All disk blocks are composed of four parts: boot block, dedicated block, I node table block, and da

users, for security reasons, require these users to log on the first time must change the password, how to implement?Modify the/etc/shadow third column to change the value of the new user to 0.7, how to change all the files in a directory (without directory) permissions to 644?Find./-type F | Xargs chmod 6448, please realize the following requirements: Only allow the use of ordinary account login, and ordinary account login, you can not enter the password to sudo switch to the root account, roo

Linux O M engineer interview question 1. File file11 is available. Use shell to query the row number awk of the empty line in file1 {if ($0 ~ /^ $/) Print NR} 'fileorgrep-n ^ $ file | awk' BEGIN {FS = ": '} {print $1}' 2. Compile ShellScript to query the row grep abc $ file1 ending with abc in file1 3. print the 1st to 3rd rows of file1 sed-n' 1, 3 P 'file1head-3 file1 2. How to forward requests from local