dd if=/dev/sda | ssh backups@192.168.1.123 "dd of=backup.img"
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===== Run from remote computer =====
dd if=/dev/sda | gzip -1 - | ssh user@local dd of=image.gz
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===== Run from local computer =====
ssh user@remote "dd if=/dev/sda | gzip -1 -" | dd of=image.gz
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