bash script for backup

[abazoskib]

i want my bash script to check if a lock file exists, if it exists, the script should keep checking till the lock file is gone, and then proceed. so far, ive made it so the script exits if the lock file is found. whats the change i need to make? i know i need a while loop, but im still learning bash syntax so hopefully someone could shed some light on this topic for me

 

if [ -f /usr/xxxx/xxxx.lock ]
then
        exit 1
else
        #!/bin/sh
        DATE=`date +%Y-%m-%e`
        mysqldump -uxxx -pXXXXX XXX_db xx_tbl > /ebs/MYSQL_BACKUPS/xx_$DATE.sql
        mysqldump -uxxx -pXXXXX XXX_db xx_tbl > /ebs/MYSQL_BACKUPS/xx_$DATE.sql
        cd /ebs/MYSQL_BACKUPS

        tar -czf mysql_backup_$DATE.sql.tar.gz  xx_$DATE.sql xx_$DATE.sql
        rm -f *.sql
fi

[trq]

Not tested.

 

#!/bin/sh

while true ; do
  attemptbackup;
done

function attemptbackup() {
  if [ -f /usr/xxxx/xxxx.lock ]
  then
    return
  else
    DATE=`date +%Y-%m-%e`
    mysqldump -uxxx -pXXXXX XXX_db xx_tbl > /ebs/MYSQL_BACKUPS/xx_$DATE.sql
    mysqldump -uxxx -pXXXXX XXX_db xx_tbl > /ebs/MYSQL_BACKUPS/xx_$DATE.sql
    cd /ebs/MYSQL_BACKUPS

    tar -czf mysql_backup_$DATE.sql.tar.gz  xx_$DATE.sql xx_$DATE.sql
    rm -f *.sql
  fi
  exit
}

[abazoskib]

so basically 'while true' will keep looping until the lock file is gone, the commands are executed and an exit is given?

[trq]

Yeah.

 

Your not going to try running this as some sort of service though are you?

[abazoskib]

i want to use it for backing up two specific tables of a mysql db every night with cron..not ok?

[trq]

Should be fine. What exactly is the lock file for?

 

I'm just a little worried the you may get into an infinite loop.

[abazoskib]

the lock file is created by another script while running. the script that creates the file also removes the file at the end of completion. and the reason i check for it is because the script that creates the script works hourly, and adds to the tables i am backing up. mysqldump locks the tables, so i cant risk losing data.

[MyUser]

Why you do not use zyxBackup? It is a high-customizable bash script that can do a lot of things like encryption, uploading to ftp. There are a lot of backup bash scripts

 

You can read more about it here Secure backup on remote server using zyxBackup and GPG