DD over SSH
I wanted to copy my pfsense disk without taking down the machine. (Moving from 3.5″ to 2.5″ disk for increased power savings) So I’m using DD and piping it over SSH to my file server. No progress bar but my drive is small.
dd if=/dev/sda | ssh root@freenas "dd of=/backup/pfsense.img"
found out adding ‘bs=4k’ or larger made transfer go little faster
dd if=/dev/sda bs=32k | ssh root@freenas "dd of=/backup/pfsense.img"
I topped out around 200mbit, with my router CPU maxed out. Must be SSH’s encryption overhead.
Credit – http://karlherrick.com/dev/2008/09/12/dd-backups-over-ssh/
DD Man Page – http://linux.die.net/man/1/dd