1, System software installation method:
1. Install software using yum (recommended)
yum install -y Software name ---Install software advantage:Software dependencies can be resolved shortcoming:Unable to implement customized installation
2. rpm installation software
rpm -ivh software package.rpm ---Install software i -- install ---Software installation v -- verbose ---Displays the installation process h -- hash ---display hash Tag information advantage:No need to rely on network installation software shortcoming:Software dependencies cannot be resolved
3. Compile and install software
(1) Configuration process:
./configure --prefix=/application/nginx --with-http_ssl_module --with-http_stub_status_module --prefix=PATH ---Modify program installation path --with-xxxx ---The software can support functions --without-xxxx ---Cancel software default function
(2) Compilation process: let the system identify the source code information
make
(3) Installation process: (compile and install)
make install advantage:Customized installation can be realized shortcoming:Software dependencies cannot be resolved Installation premise:A compiled software source package is required Install software:Trilogy
4. Installing software in binary package mode
advantage:Save software installation time shortcoming:Software dependencies cannot be resolved Installation premise:Binary package required setup script:Unzip--Save the extracted directory to the specified system directory---You can use it directly
2, Detailed description of file attributes:
1. Document type concept description
(1) File type introduction:
The file type information does not change with the file extension name
(2) Document type description:
(1) Ordinary file:(f/-) /Plain text file/Binary file/Data file (2) Catalog file:(d) (3) Link file:(l) Soft link file (4) Equipment file:(character/block) Character device file/Block device file (5) Socket file:(socket) Socket interface file (6) Pipeline file:(pipe) Pipeline file
(3) File type viewing method:
file file information: catalogue link to configure journal script compress ... .conf ---configuration file .log ---log file .sh ---Script file .py ---Script file
2. File directory related commands
(1) Display command absolute path information (which)
Display command file absolute path information (which/whereis):
which timedatectl
which command to view the command file path range:
which sed
The PATH environment variable can specify the PATH range where the command file is saved:
echo $PATH
You can modify the PATH environment variable temporarily or permanently:
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin:/usr/local" which sed PATH="$PATH:/usr/local"
(2) Quickly locate file path information
When locating the specified file information, you need to retrieve the database file first
updatedb ---Update or create database files locate fff01.txt ---After the database file is updated, find the file to locate the path of the file ll /var/lib/mlocate/mlocate.db file /var/lib/mlocate/mlocate.db
(3) Quick find data information command: find
Command syntax structure:
find Find path range find data criteria ---Quickly find data information
Method 1: find data by name
Given the file name, make an accurate search
find /root/desktop -name "fff01.txt"
Unknown file name, fuzzy search
find /root/desktop -name "ff*.txt" find /root/desktop -name "*.txt" find /root/desktop -name "ff*"
Ignore file name case lookup
find /root/desktop -iname "Ff*.txt"
Method 2: find data according to file type
Recursively find all directory type data
find /etc -type d find /etc -type d|wc -l
Find data by directory level
find /etc -mindepth 1 -type f find /etc -mindepth 1 -type f|wc -l find /etc -maxdepth 1 -type f find /etc -maxdepth 1 -type f|wc -l
Method 3: find data according to file size
Find less than how much data
find /etc -size -30k|wc -l
Find data larger than how much capacity
find /etc -size +30k|wc -l
Find data of specified capacity
find /etc -size 30k
Method 4: search according to time information
Indicates how many days ago the data was
find /oldboy/ -mtime +60
Data within days
find /oldboy/ -mtime -60
Represents data that is exactly 60 days from the current time
find /oldboy/ -mtime60
(4) Data compression and packaging command tar
Packed compressed data relative path:
tar zcvf /Compressed file save path/Compressed package file information data information to be compressed 01 data information to be compressed 02 03 04 ... tar zcvf ./ss.tar.gz ./fstab_2021-08-17_08:59:31 ./ifcfg-eth0_2021-08-17_08:59:31 z ---use gzip Compress and pack data c ---Create a compressed package file v ---Displays the data compression process f ---Identify the path information of the compressed package
Absolute path packed compressed data:
tar zcvf /root/backup/ssd.tar.gz /var/log tar: Removes the beginning from the member name“/" ---Compressed data information. If an absolute path is used, it will be compressed/Directory information removal explain:Remove/The root directory information is mainly used to avoid that the data in the original directory will be overwritten after decompression (default setting))
Compressed data exclusion function:
tar zcvf /root/s1.tar.gz /root/backup/ --exclude=/root/backup/fstab_2021-08-18_08:38:43 ---Exclude single data information tar zcvf /root/s2.tar.gz /root/backup/ --exclude-from=/root/desktop/s.txt ---Exclude multiple data information
To view compressed package data information:
tar tf Compressed package file ---View the contents of the compressed package file t ---The list displays the data information in the compressed package,However, the compressed package will not be decompressed
Process of decompressing data information:
tar zxvf × ---Extract data information in pressure sink package
find deletes some data information of the directory
Mode 1:Locate the directory itself for exclusion
find /root/backup/ -mindepth 1 ! -name "*.tar.gz"|xargs rm -rf
xargs ---After the pipe symbol, it means that the result information generated by the command in front of the pipe symbol is converted into parameter information and handed over to the user xargs Subsequent commands are processed
Mode II:Delete some data
find /root/backup/ -mindepth 1 ! -name "*.tar.gz" -delete
Mode III:Delete some data
find /root/backup/ -mindepth 1 ! -name "*.tar.gz" -exec rm -rf {} \;
Compress or decompress data: why move the / directory in front of the data information
The first course: Environmental preparation
Create important profile information: cat /conf/oldboy.conf oldboy123
The second process: compress and save backup data information
tar zcvPf /backup/oldboy.tar.gz /conf/oldboy.conf/ conf/oldboy.conf tar tf / backup/oldboy.tar.gz tar:Removes the beginning from the member name“/" / conf/oldboy.conf ---View data not moved out/information
The third process: modify and edit the original configuration file
cat /conf/oldboy.conf oldboy123 456 789
The fourth process: decompress the data information (do not move out of the root directory)
tar xPf /backup/oldboy.tar.gz
View that the original data information is overwritten
cat /conf/oldboy.conf oldboy123
3. File permission information
Value information corresponding to permission symbol
r=4 w=2 x=1 - = 0 rw-r---wx 411 -wxr-xr-- 367 r--rwx--x 542 conclusion:Under normal circumstances,The file data permission has 9 bits == 3 Special permission bit
4. File users and user groups
File user information
Introduction to user information concept:
user: Corresponding data users can be managed, and corresponding process users can be managed The system will identify the user according to the user number == UID User group:Multiple people can manage a data file at the same time, and the permissions of multiple people can be set and adjusted at the same time The system identifies the user group according to the user group number == GID Hard disk four hundred == Zhang San bought it Owner Storage server 40000 == Zhang San, Li Si, Wang Wu raised money to buy power–group
System user classification:
System super administrator root(emperor) 0 Have absolute control over the system System virtual user nobody(puppet) 1-999 Can manage processes/Data information(Unable to log in to the system/Cannot have home directory) Ordinary users of the system admin(minister) 1000+ auxiliary root User management system(Must be root Assign special rights to users)
5. File attribute time information
File time type:
Access time (atime): Access time--The time when the file was viewed and opened Modify time (mtime): Modification time--The time when the file data content was changed Change time (ctime): Change time--Change time of file attribute information
Just after creating a file, access the file to view the time information
touch ss.txt stat ss.txt Access: 2021-08-19 16:50:53.086154957 +0800 Modify: 2021-08-19 16:50:53.086154957 +0800 Change: 2021-08-19 16:50:53.086154957 +0800 File access view: cat ss.txt stat ss.txt Access: 2021-08-19 16:54:29.572770926 +0800 ---Access time change Modify: 2021-08-19 16:50:53.086154957 +0800 Change: 2021-08-19 16:50:53.086154957 +0800 Modify file content information: vim ss.txt stat ss.txt Access: 2021-08-19 16:57:10.843212956 +0800 ---The file was opened and accessed while editing the file Modify: 2021-08-19 16:57:10.843212956 +0800 ---Time after message change Change: 2021-08-19 16:57:10.843212956 +0800 ---File size attribute change Modify file attribute information:: chown admin ss.txt stat ss.txt Access: 2021-08-19 16:57:10.843212956 +0800 Modify: 2021-08-19 16:57:10.843212956 +0800 Change: 2021-08-19 17:03:10.491198713 +0800 ---When the file permission attribute changes, it will change
View the display time as required
date "+%Y-%m-%d %A %H:%M:%S" ---View the current system time date "+%F" ---View current system date(specific date) date "+%T" ---View the current system time(Hour, minute and second) date -d "-1 day" ---Show how many days ago in the past date -d "+10 day" ---Displays the number of days in the future 11 00, January 1: 00 Day before data backup(10 March 31) backups-generate hosts-11 January 1 cp /etc/hosts /root/backup/hosts-$(date +%F_%T -d "-1 day") hosts-10 March 31
Modified on:
date -s "2020-12-12 12:12:12" ---Complete adjustment time information