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Watching dd progress

Fabian (of RPMforge and CentOS fame) wrote a blogpost about using pv (pipe viewer) to watch a datastream through a pipe, such as a dd-over-ssh copy from one machine to another. I knew pv existed, but I've often used dd on systems where pv wasn't available (e.g. rescue CD), or used dd without sending data through pipes. Even in these situations, you can keep an eye on dd's progress: open another terminal window, then run

# while sleep 10; do killall -USR1 dd; done


and switch back to the shell where dd is running. It will show its status every 10 seconds.
Note, your version of dd needs to support this. The dd from RHEL3 doesn't (version 4), but the dd from RHEL5 does (version 5) !

Comments

Unknown said…
I usually use this:

# while killall -USR1 dd; do sleep 10; done

No need to break the loop if the dd process stops :)
Bert de Bruijn said…
Good point. I often use "while sleep" on this and other loops because the loop exits when you ctrl-c the running sleep command (because of the non-zero exit status).

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