Question about using RDX Tape drive on multiple partitions

We have 4 partitions and 1 External RDX tape drive

Someone else set the device up and is no longer available.

Device description . . . . . . . . : TAP01

Option . . . . . . . . . . . . . . : *BASIC

Category of device . . . . . . . . : *OPT



Device type . . . . . . . . . . . : 63B8

Device model . . . . . . . . . . . : 0D2

Resource name . . . . . . . . . . : RMS01

Local internet address . . . . . . : *NONE



I was told we should be able to use the RDX tape drive on all
partitions but it can only be varied on on a single partition at a
time.

How can a single external RDX drive be used over multiple partitions?

Power8 running 7.2



It works fine on our main partition.

But when I vary it off then go to another partition it will not vary
on

Error:

Message ID . . . . . . : CPD27D2 Severity . . . . . . . : 40


Message type . . . . . : Diagnostic


Date sent . . . . . . : 03/22/18 Time sent . . . . . . :
15:27:07




Message . . . . : Device TAP01 vary on failed.


Cause . . . . . : The device resource is currently in use by object
RMS01

type *DEVD. If the object name and type are blanks, either the
resource is

in use by the Dedicated Service Tools (DST), another client, or the
data is

not available.


If a media library drive is being allocated, either the drive may
already

be allocated to another media library device that is varied on or
the drive

may be in use through an alternate path.


Recovery . . . : Do one of the following:


-- Vary off the active device and vary on device TAP01.


-- Use the active device instead of device TAP01.


-- Deallocate the device on Network Server RMS01.


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