Linux training record: A little effort every day

Linux training record: make a little effort every day-Linux general technology-Linux technology and application information. The following is a detailed description. Author: dream start point

A busy week has passed. After graduation, I often feel like this: how can time be so fast! I remember that when I was in college, I thought about the weekend from the first class on Monday. When I arrived at the weekend, I thought about whether there were any holidays in this month, for example, 5.1 and 10.1. Haha. I have not rested for several weeks, and I have worked very hard this week. I have worked overtime for three consecutive nights until. Although I feel very tired, I will fall asleep on the bus after class every weekend, very Fragrant), but the psychology is very full, (don't stop because of the superior environment, try a little bit every day, haha) I like this feeling.

After class yesterday, I went home all the way. While singing, I thought about my MacOs. At noon, Miss Huang gave me

A MacOS X10.4.6 CD was finally completed all afternoon (I was still installing it during the lecture by Mr. Huang). To tell the truth, the visual effect of Apple's system is really great, but when I got home, I tried to install it for one night (more than a.m.). I don't know why, alas, it seems that my poor R60e is not happy to enjoy this kind of "luxury" system. If there are so many nonsense, let's start with the question (File Permission and user management are important in Linux) some experiences in the class will be shared with you:

Yirong New Network System Integration Project (Work Manual)
Rongxin Network System Integration Project (Linux origin and basic commands)
Use of shell

2. File permissions and user management
Application installation and management

1 If we use F-ssh to remotely manage machines, garbled characters may occur sometimes.
Solution: # system-config-language, graphical interface, change the language to English
# Reboot

2 after the virtual machine is installed, the default resolution is small and it looks uncomfortable.
Solution: System Tools-hardware-CRT settings-double-click-select the specified resolution
# Rebooe

3. IP address change
Solution:
A. # setup graphical interface
B. # vi/etc/sysconfig/network-scripts/ifcfg-eth0, modify
C. #/etc/init. d/network reload

4. query the username and Group of the current logon user.
# Whoami or # groups

5. In linux, directories and files are common files. to access a directory, the permission for this directory must be at least r-x. You can also use numbers to set permissions.

6. chmode can only repair the permissions of the file and directory, but its owner (creator) remains unchanged. It can be modified only through chown.

7. When creating a user, for example, # useradd-g dba-G manager-c "DB administrator"-d/DB user1, In this command, the user name can only be placed after all parameters, otherwise, the parameters have not been passed.

8. Two centOS are recommended. (As Mr. Huang said, it's really nice to have fun playing with various operating systems)
CERNET: ftp: // 202.38.97.230/centos
Very good site: ftp://ftp.net.usf.edu
Australia site, fast: http://www.pacific.net.au/mirror/linux.php
Debian Redhat Fedora Gentoo Mandriva Knoppix SuSE
Slackware Yellow Dog cAos CentOS Ubuntu tinysofa FreeBSD OpenBSD
NetBSD DragonflyBSD archlinux StartCom

9 when installing software with rpm, you can use # make clean to delete the software if any problem occurs in the middle.
There must be a correlation between software. When You Need To uninstall a software in linux, you can use the following command to view its association.

# Rpm-qa | grep software name
# Rl-ql file name

10 common installation commands: rpm-ivh XX. XX. rpm
Common commands for compression: # tar-cvf xx.xx.tar (target file) source file
Common commands for decompression: # tar-zxvf xx.xx.tar.gz is equivalent to # gunzip xx.xx.tar.gz
# Tar-jxvf xx.xx.tar.bz2 is equivalent to # bunzip2-jxvf xx.xx.tar.bz2

Note: Pay attention to the directory during decompression. The # tar xx.xx.tar-C directory can be decompressed to the specified directory, but it seems that you cannot specify the directory in gunzip and unzip2, therefore, it is best to use mv to move the tar package to the specified directory and then parse it.

11 good habits: After installing any software, add "Shortcuts" to facilitate future use and management.
# Vi/etc/profile
Add export PATH = $ PATH:/usr/local/lumaqq/bin (directory of the program) at the end)
# Env | grep PATH
#./Etc/profile execution to make it take effect
# Simply enter the software name.

12 when you use su to switch users, the-u parameter will jump to the user's home directory. If no parameter is added, keep the directory before switching.

13. Small experiments on Permissions

Master group --- additional group --- user --- file ---- permission (although both user1 and user2 belong to the manager group, the permission is determined by the unique master Group)

Dba manager user1 1.txt user1cannot upload 2.txt
Manager user2 2.txt user2 2.txt

14 A small experiment on text prompts during logon and exit
There are two hidden files in each user's home directory. bashrc)

. Bash_logout (modify it to display a text prompt when the user logs out, but only when the user's home directory exits) File