USB device activity when not mounted

Mike Clarke jmc-freebsd2 at
Thu Jun 14 13:38:06 UTC 2012

On Thursday 14 June 2012 07:05:11 Polytropon wrote:
> I don't think that's a problem. I've got a USB stick here
> that has a blinkenlight as soon as it's powered on (plugged
> in), even if there is no reading / writing / mounting activity.
> After you've successfully performed umount, the USB stick _is_
> synced and can safely be removed, no matter what you assume
> the funny lights want to tell you.
> Maybe that's just a "modern feature" to make the USB stick "more
> entertaining". :-)

I have a Kingston one here which does appear to only blink while data is being 
transferred but one thing I have noticed is that the light continues to blink 
for a few seconds after the umount command completes. Presumably syncing is 
not compled until a few seconds after umount. Perhaps it's always safer to 
wait a few seconds after umounting before removing any USB storage device?

Mike Clarke

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