You are hereBlogs / David Grant's blog / rsync --delete is dangerous!

rsync --delete is dangerous!


By David Grant - Posted on 11 July 2008

I hosed my entire home directory on this server last night with an incorrect rsync command. I tried syncing my svn repository to the server like this:

rsync -az -e ssh --delete /var/svn/repos/ servername:/home/username/

The problem is that I had an extra slash on the end of "/var/svn/repos/". Without the extra slash, it would create a directory called repos inside servername:/home/username and sync it with /var/svn/repos. With the slash, it syncs the contents of "/var/svn/repos" with the contents of servername:/home/username, thus causing all files in servername:/home/username to be deleted because of the --deleted command.

What I could have done instead is create a directory on the remote server called repos and then rsync like this (actually you don't need to create repos first):

rsync -az -e ssh --delete /var/svn/repos/ servername:/home/username/repos

Or I could have done this:

rsync -az -e ssh --delete /var/svn/repos servername:/home/username

The last command will create a directory called repos in servername:/home/username and it will sync it but not delete anything in servername:/home/username. Add a trailing slah to /var/svn/repos and it will!

Luckily I had a nightly backup of my entire home directory on my local server's external backup drive. I was worried because although I make these nightly backups I haven't actually inspected them in a while. Fortunately everything was intact.

Tags

Hi David,

I was wondering what's the best command that I should use if I want to syncronize a filesystem called /zsync to another filesystem in other server called /zsync?A suggestion would much appreciated.Thanks in advance.

Tarmizee

Use the "-n print what will be done, but do nothing" switch, and stop wheening around !

-n, --dry-run
This makes rsync perform a trial run that doesn't make any changes (and produces mostly the same output as a real run). It is most commonly used in combination with the -v, --verbose and/or -i, --itemize-changes options to see what an rsync command is going to do before one actually runs it.

Huo! Thanks.

It utilizes rsync --del among other things so you can see another example of how to do it correctly.

Linux backup via SSH

Post new comment

The content of this field is kept private and will not be shown publicly.
  • Allowed HTML tags: <a> <em> <strong> <cite> <code> <ul> <ol> <li> <dl> <dt> <dd> <blockquote> <s> <img> <h2> <h3>
  • Lines and paragraphs break automatically.
  • You can enable syntax highlighting of source code with the following tags: <code>, <blockcode>. The supported tag styles are: <foo>, [foo].

More information about formatting options

CAPTCHA
This question is for testing whether you are a human visitor and to prevent automated spam submissions.
Image CAPTCHA
Enter the characters shown in the image.
By submitting this form, you accept the Mollom privacy policy.