On Thu, 2020-10-22 at 07:56 -0400, Jonathan Billings wrote: > It’s not a terrible idea to use sync. You absolutely should not be > running dd to a device that is used in a mounted file system. It > should be unmounted first. Then there is no risk of sync corrupting > the disk. I'd always understood that any drive you were dd'ing to should be unmounted. You wouldn't want another thing to try and write to it as well. However, has anyone else encountered this behaviour: You plug in your spare flashdrive. You look for its device name (e.g. you "dmesg|tail"), and you (correctly) determine it's /dev/sde (for example). You notice that the device appears to be mounted, even though you've not mounted it, and you've (previously) configured your computer not to auto-mount flashdrives. So, you unmount that device. And, now, /dev/sde is not available to "dd" anything to. > You could include ‘conv=sync’ in your dd command if you want to > ensure that everything is written, but it might not as fast, > depending on the block size. I think that's one reason why advise was to use "oflag=direct" as a dd parameter (avoiding caching, so you shouldn't have to double check things had synced before removing). But I was under the impression that conv=sync has a different purpose. -- uname -rsvp Linux 3.10.0-1127.19.1.el7.x86_64 #1 SMP Tue Aug 25 17:23:54 UTC 2020 x86_64 Boilerplate: All unexpected mail to my mailbox is automatically deleted. I will only get to see the messages that are posted to the mailing list. _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx
