[SOLVED] dd command not working

lazydog · 11-16-2018, 09:51 PM

Hello everyone,

So I'm trying to make a backup of my windows drive using dd but the following command doesn't seem to work all I get is a '>':

Code:

backups # dd if=/dev/nvme0n1 conv=sync,noerror status=progress bs=64K | gzip -c > /backups/windows/windows-"`date +"%Y%m%d_%H%M"`.img.gz
>

But if I do the same without the date it works:

Code:

dd if=/dev/nvme0n1 conv=sync,noerror status=progress bs=64K | gzip -c > /backups/windows/windows.img.gz

What am I doing wrong with the date as I would like the date in the filename.

Anyone got any ideas why this isn't working?

Thanks for your help with this.

ehartman · 11-16-2018, 09:57 PM

Quote:

Originally Posted by lazydog

Hello everyone,

So I'm trying to make a backup of my windows drive using dd but the following command doesn't seem to work all I get is a '>':

Code:

backups # dd if=/dev/nvme0n1 conv=sync,noerror status=progress bs=64K | gzip -c > /backups/windows/windows-"`date +"%Y%m%d_%H%M"`.img.gz
>

But if I do the same without the date it works:

The date command contains too many " chars, try removing the one before the first back-quote.

lazydog · 11-16-2018, 10:45 PM

Bingo! Thnx. Just over looked that. Guess doing this when you are tired isn't a good idea.

ehartman · 11-16-2018, 11:59 PM

Quote:

Originally Posted by lazydog

Bingo! Thnx. Just over looked that. Guess doing this when you are tired isn't a good idea.

BTW: you can simplify the date command by using %F

Code:

date "+%F_%H%M"

which is better looking or even eliminate the time altogether as you normally don't make more then one backup per day. Then you can eliminate the double quotes altogether

Code:

date +\%F

lazydog · 11-17-2018, 11:30 PM

ehartman, Thnx for this information. The %F inserts dashes in the date which is what I'm trying to stay away from.

pan64 · 11-18-2018, 03:52 AM

just a comment (or two): it was not the dd, so your title is misleading (you stated in your first post, without date it worked).
in similar cases I would suggest to generate the filename first, put/store it into a variable and use that:

Code:

MY_FILE=$(date +"windows-%Y%m%d_%H%M.img.gz")
dd ... | gzip ... > "/this/dir/${MY_FILE}"     # << use " here

This make it more readable, (you can use set -xv to check how does it really works) and yes, more stable - as you can see.
And finally if your problem is solved, please mark the thread solved. Also if you wish to say thanks to someone just click on yes.

lazydog · 11-19-2018, 10:36 AM

One of the things I like about linux, there is more than one way to get the job done.