Transfer image compressed via SSH

Version 3.2

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This article describes the how to of copying Harddrive Images compressed via SSH.

Introduction

The copy procedure can be easily done with standard Linux system tools.

To copy an image from your local device /dev/sda to a virtualization host, execute the following command:

dd if=/dev/sda | gzip | ssh root@<HOST> " gunzip | dd of=/var/lib/libvirt/images/image.img

Explanation

dd reads the Harddrive /dev/sda/, the output is being compressed by gzip. The compressed file will be transmitted to the foreign host with ssh and there decompressed with gunzip which writes the file to the given path. The block size of 2 Kbyte makes the transmission of bigger files more performant.