Results 1 to 3 of 3

Thread: BASH scripting help requested please

  1. #1
    Join Date
    Mar 2014
    Beans
    2

    BASH scripting help requested please

    Hi!
    I am working on backup automation of an Ubuntu 12.04 LTS instance running in Azure. I have used the example located at https://help.ubuntu.com/10.04/serverguide/backup-shellscripts.htm. I have modified it to suit my needs by changing the scope and also adding a mysqldump to grab a snapshot of the mysql database.

    I am using the following code in a file called backup-wp.sh:
    Code:
    #!/bin/sh
    ##################################
    #
    # Backup script for wordpress
    #
    ##################################
    
    
    #what to backup
    backup_files="/home /var/www"
    
    
    #where to backup
    target= "/backup"
    
    
    #create archive name
    day=$(date +%A)
    hostname=$(hostname -s)
    archive_file = "$hostname-$day.tgz"
    
    
    #wordpress backup file name
    wpbackup_path = "/home/admin-user"
    wpbackup_file = "$wpbackup_path/$day-mysite-wordpress.sql"
    
    
    #backup mysql
    mysqldump mydb > $wpbackup_file
    
    
    #print start status message.
    echo "backing up $backup_files to $dest/$archive_file"
    date
    echo
    
    
    #backup the files using tar
    tar czf $target/$archive_file $backup_files
    
    
    #print end status message.
    echo
    echo "backup complete"
    date
    echo
    The script currently lives in my home directory and has been set to +x.

    When I run the script using bash backup-wp.sh I get the following result:


    backup-wp.sh: line 12: /backup: Is a directory
    backup-wp.sh: line 17: archive_file: command not found
    backup-wp.sh: line 20: wpbackup_path: command not found
    backup-wp.sh: line 21: wpbackup_file: command not found
    backup-wp.sh: line 24: $wpbackup_file: ambiguous redirect
    backing up /home /var/www to /
    Mon Mar 24 23:40:51 UTC 2014


    tar: Removing leading `/' from member names
    tar (child): /: Cannot open: Is a directory
    tar (child): Error is not recoverable: exiting now


    backup complete
    Mon Mar 24 23:40:51 UTC 2014


    I am stuck trying to figure out what's wrong.... the example is for 10.xx but I would expect it to work. Can someone please point me in the right direction as to why bash isn't allowing me to define a variable referencing a backup?

    Many thanks.

  2. #2
    Join Date
    Mar 2014
    Beans
    2

    Re: BASH scripting help requested please

    I managed to solve this. It was a syntax issue. Apparently bash likes messy code and hates spaces.

    This is a no-go and will not work.
    target = "/backup"

    This does work
    target="/backup"

    Hope that helps others who fight with this problem.

  3. #3
    Join Date
    Jul 2007
    Location
    Poland
    Beans
    4,402
    Distro
    Ubuntu 14.04 Trusty Tahr

    Re: BASH scripting help requested please

    I managed to solve this. It was a syntax issue. Apparently bash likes messy code and hates spaces.
    It has nothing to do with messy code, remember that bash is used to run commands and treats spaces as parameter delimiters. Spaces actually matter here, unlike in other languages. = sign with no spaces around is how bash recognizes assignments. How would bash differentiate between assignment and command execution?

    Code:
    grep = file      # run grep looking for = in file
    target = /backup # run command 'target' with 2 params: '=' and '/backup'
    target=/backup   # this is an assignment
    line 1 and 2 are the exact same situation

    any bash manual mentions it in the chapter about variables.
    Last edited by Vaphell; March 25th, 2014 at 06:53 PM.
    if your question is answered, mark the thread as [SOLVED]. Thx.
    To post code or command output, use [code] tags.
    Check your bash script here // BashFAQ // BashPitfalls

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •