cannot access pass device from within jail

Dan Langille dan at
Sun Dec 17 19:52:41 UTC 2017


What suggestions do you have for where I should look next? I'm happy to start installing various builds of FreeBSD in order to track down which commit caused this.

I'm trying to access a tape library from within a jail running on a FreeBSD 11.1 host.  sa(4) devices are working (e.g. I can rewind nsa0).

pass(4) devices (i.e. the tape changer ch0) are not working.  This morning I posted to -scsi@:

The device appears in the jail and has appropriate permissions.  This access was granted
via /etc/devfs.rules using the same approach I used for FreeBSD 10.3

The permissions in the jail:

[root at bacula-sd-02 ~]# ls -l /dev/pass7
crw-------  1 root  operator  0x74 Dec 16 21:52 /dev/pass7

The command in the jail:

[root at bacula-sd-02 ~]# mtx -f /dev/pass7 status 
cannot open SCSI device '/dev/pass7' - Operation not permitted

Here is the truss output of the command in question:

Thank you.

Dan Langille - BSDCan / PGCon
dan at

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