K3b permissions are driving me nuts!

Derek Broughton news at pointerstop.ca
Mon Jun 19 12:06:42 UTC 2006

Lee McLain wrote:

> Hi everyone,
>    This is an issue that is really bugging me and I can't seem to find a
> proper fix for it.
>    I am running Dapper on an Inspiron 6000. K3b keeps telling me that
> cdrecord doesn't have permission for the device.  Upon further checking,
> it seems that cdrecord is trying to use /dev/sg0 even though K3b says it's
> using /dev/sg1. 

Really?  I wouldn't expect the CD device to be on sg1, _but_ for scsi
CD/DVDs k3b requires access to /dev/sg0 which is a scsi control device, and
k3b doesn't report that.

> I try to add that device(sg0) and K3bsetup tells me that 
> it isn't a valid device.

Not for reading and writing on, anyway.

>    I change the permissions of /dev/sg0 to 666 and K3b then works.

There's the clue - you should never need it to be 666.  As Norton said, you
should be in the cdrom group, but iirc some versions of udev don't actually
make sg0 owned by cdrom, either, in which case you need to add the
following to /etc/udev/rules.d/15local.rules (creating the file if

  BUS=="scsi", KERNEL=="sg[0-9]", NAME="%k", GROUP="cdrom"

> Unfortunately, after rebooting, the permissions go back to what they were
> before.  This sucks.

It's normal, since the device doesn't exist between boots.

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