Shell script realizes the scheduled backup of MySQL database on two computers

1 Origin and purpose

There's a need recently , It is required to realize dual computer backup of a database , Back up every morning , The main machine is required to keep only the records of the last 15 days . A thoughtful study （ insane baidu）, We decided to use shell Scripts add timed tasks to achieve this requirement .

Considering some friends mysql Use docker Deploy , Finally, we will post docker Deployment script in environment .

Environmental preparation ：

1. Both are installed ssh Machine , Ensure that the network usually . The cross library replication command we use scp be based on openssh-clients-XXX, So basic ssh Environmental Science .
2. mysql The machine where the service is located Expect The command is normal
3. mysql Normal service .（docker Containers can also be used ）

Here is a section of offline automatic installation expect Command script

#!/bin/bash
CURRENT_DIR=`pwd`

function install_expect()
{
    echo "install start..."
    cp expect-5.45.0.tar.gz tcl8.4.11-src.tar.gz /usr/
    cd /usr/
    tar -zxvf expect-5.45.0.tar.gz
    tar -zxvf tcl8.4.11-src.tar.gz
    cd tcl8.4.11/unix
    ./configure --prefix=/usr/tcl --enable-shared
    make -j8
    make install
    cp tclUnixPort.h ../generic/
    
    cd ../../expect-5.45
    ./configure --prefix=/usr/expect --with-tcl=/usr/tcl/lib --with-tclinclude=../tcl8.4.11/generic
    make -j8
    make install
    ln -s /usr/expect/bin/expect /usr/tcl/bin/expect
    ln -s /usr/expect/bin/expect /usr/bin/expect
    cd ..
    rm -rf expect-5.45.0.tar.gz tcl8.4.11-src.tar.gz
    cd $CURRENT_DIR
    echo "install finished..."
    
}
install_expect
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In the download address of the two packages needed to put the above script

nchc.dl.sourceforge.net/sourceforge…

sourceforge.net/projects/ex…

2 Confirm environment

In this step, let's manually confirm the key commands of a script , Ensure that the script can execute normally .

2.1 Export database sql Script

mysqldump -u Database user name  -p Database password   The name of the database to be exported  > /mnt/data/mysql_backup/ Exported sql Script name .sql
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sql The script is exported normally .

2.2 Cross machine copy

scp -P ssh Port number  /mnt/data/mysql_backup/ Exported sql Script name .sql  The user name of another machine, such as [email protected] Another machine IP:/mnt/data/mysql_backup/
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The first copy failed , Cause another machine needs to be guaranteed /mnt/data/mysql_backup/ This path exists , Execute again to succeed .

2.3 docker Container confirmation environment

# Database backup 
docker exec -u root mysql bash -c 'rm -rf /usr/local/pm/* && mysqldump -u user name  -p password   Database name  > /usr/local/pm/pm_yantai_$(date "+%Y-%m-%d").sql'
#sql Copy out 
docker cp mysql:/usr/local/pm/pm_yantai_$(date "+%Y-%m-%d").sql 
# Cross machine copy 
scp -P ssh Port number  /mnt/data/mysql_backup/ Exported sql Script name .sql  The user name of another machine, such as [email protected] Another machine IP:/mnt/data/mysql_backup/
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3 Build script

3.1 The script content

1. Not dockermysql

#!/bin/bash
# export sql Script 
echo $(date "+%Y-%m-%d") backup start
echo mysql backup start
mysqldump -u Database user name  -p Database password  pm_prod2.0 > /mnt/data/mysql_backup/pm_shandong_$(date "+%Y-%m-%d").sql
echo mysql backup finish
#scp Cross machine backup 
echo sql scp start
/usr/bin/expect <<-EOF
set timeout -1;
spawn scp -P ssh Port number  /mnt/data/mysql_backup/pm_shandong_$(date "+%Y-%m-%d").sql  User name of another machine @ Another machine IP:/mnt/data/mysql_backup/
expect {
    "*password:" {send " Another machine password \r";exp_continue;}
    "yes/no" {send "yes\r";}
}
EOF
# Delete expired sql
echo remove file /mnt/data/mysql_backup/pm_shandong_$(date -d "7 day ago" +%Y-%m-%d).sql
rm -rf /mnt/data/mysql_backup/pm_shandong_$(date -d "7 day ago" +%Y-%m-%d).sql
echo finish! The file is pm_shandong_$(date "+%Y-%m-%d").sql
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2.docker Containers mysql

#!/bin/bash
echo $(date "+%Y-%m-%d") backup start
echo mysql docker backup start
docker exec -u root mysql bash -c 'rm -rf /usr/local/pm/* && mysqldump -u user name  -p password   Database name  > /usr/local/pm/pm_yantai_$(date "+%Y-%m-%d").sql'
echo mysql docker backup finish
echo sql copy start
docker cp mysql:/usr/local/pm/pm_yantai_$(date "+%Y-%m-%d").sql /usr/local/sdyy/pm/mysql_backup/pm_yantai_$(date "+%Y-%m-%d").sql
echo sql scp start
/usr/bin/expect <<-EOF
set timeout -1;
spawn scp -P ssh Port number  /usr/local/sdyy/pm/mysql_backup/pm_yantai_$(date "+%Y-%m-%d").sql  User name of another machine @ Another machine IP:/usr/local/sdyy/pm/mysql_backup/
expect {
    "*password:" {send " Another machine login password \r";exp_continue;}
    "yes/no" {send "yes\r";}
}
EOF
echo remove file /usr/local/sdyy/pm/mysql_backup/pm_yantai_$(date -d "15 day ago" +%Y-%m-%d).sql
rm -rf /usr/local/sdyy/pm/mysql_backup/pm_yantai_$(date -d "15 day ago" +%Y-%m-%d).sql
echo finish! The file is pm_yantai_$(date "+%Y-%m-%d").sql
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3.2 Manually execute the script to confirm that it is normal

sh mysql_backup.sh
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Be careful ： If you are from windows Directly uploaded shell Script , The following error should be reported .

This is because you have more backup files ？

The general reason is windows The file format created is dos Format reason .

The solution is as follows ：

1. stay Windows Down conversion ：

Use some editors such as UltraEdit or EditPlus Tools such as the script code conversion , Then put it in Linux In the implementation of . The conversion method is as follows （UltraEdit）：File-->Conversions-->DOS->UNIX that will do .

2. stay Linux Down conversion use vim Open the sh file , Input ： :set ff enter , Show fileformat=dos, Reset the file format ： :set ff=unix Save and exit : :wq

Execute the order again

4 Timing task

1. Edit scheduled tasks

crontab -e
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Add the following line at the end

0 3 * * * /mnt/data/mysql_backup/mysql_backup.sh >> /mnt/data/mysql_backup/backup.log
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The front is corn expression , On behalf of three o'clock every day .

Here is a paragraph that may be used cron expression .

And then shell Script absolute path , The execution log will be appended to the log file later .

Save and exit .

2. Query the current scheduled tasks

crontab -l
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3. Add executable rights

chmod +x /mnt/data/mysql_backup/mysql_backup.sh
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thus , Task to complete ！