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Command Line Fu - Using tar over SSH

A neat little snippet when migrating datasets between servers or creating archives to remote servers when disk space is limited. Here are some examples I've used extensively when migrating some RHEL7 Servers to RHEL8:

Creating archive locally and push to remote server:
 [root@kvm ~]# tar -cvpJf - /srv/kvm/vm-images | ssh root@nas.archyslife.lan 'cat > /var/backup/vm-images.tar.xz'
Create archive remotely and pull to local server:
 [root@nas ~]# ssh archy@kvm.archyslife.lan 'tar -cvpJf - /srv/kvm/vm-images' > /var/backup/vm-images.tar.xz
Pull archive from remote server and extract locally:
 [archy@kvm ~]$ ssh archy@nas.archyslife.lan 'cat /var/backup/vm-images.tar.xz' | tar -xvJf - -C /
Push archive from local server to 
 [archy@nas ~]$ cat /var/backup/vm-images.tar.xz | ssh archy@kvm.archyslife.lan 'tar -xvpJf - -C /'
Feel free to comment and / or suggest a topic.
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Comments

  1. Murugan ChandrasekarMarch 5, 2021 at 6:55 AM

    tar -cvpJf -

    what is the meaning of "-" at the end above?

    ReplyDelete
    Replies
    1. Adrian "Archy"March 5, 2021 at 7:46 AM

      The '-' will return the output of the tar command to the terminal where you can redirect it using '<' or '>'.

      Delete
  2. Murugan ChandrasekarMarch 5, 2021 at 7:28 AM

    can you please post the same work for Rsync command?

    ReplyDelete
    Replies
    1. Adrian "Archy"March 5, 2021 at 7:58 AM

      An example on how to use rsync over ssh (if it's just about that) can be found here:
      https://archyslife.blogspot.com/2018/12/creating-backups-in-linux-with-tar-and.html

      Delete
  3. Murugan ChandrasekarMarch 8, 2021 at 10:36 AM

    Thank you so much.

    I'm expecting this kind of technical post. Good work!

    ReplyDelete

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