Symptoms
Unable to remove hdiskpower device on AIX system running Veritas DMP.
Cause
Unable to remove hdiskpower device on AIX system.As part of an unmasking procedure, the user is attempting to remove a hdiskpower pseudo device from an AIX system:# rmdev -Rdl hdiskpower30Method error (/etc/methods/ucfgpowerdisk):0514-062 Cannot perform the requested function because the specified device is busy.Looking at disk related outputs, we can see that hdiskpower30 is under Veritas Volume Manager(VxVM) and Veritas DMP (VxDMP) control:# inq/dev/vx/rdmp/hdiskpower30 :EMC :SYMMETRIX :5876 # vxdmpdbprint | grep hdiskpower30 46> name=hdiskpower30, ap=1, fp=0, tp=1, state=ENABLED 1> subpath=hdiskpower30 state=ENABLED Veritas VxDMP is holding the device which is causing rmdev (and powermt remove) to fail. The vxdmp exclude command needs to be run prior to removing the device from PowerPath and the Operating System.
Resolution
The relevant device needs to be firstly removed from Veritas DMP control, then taken out of PowerPath control and finally removed from the Operating System:# vxdmpadm exclude dmpnodename=hdiskpower30# powermt remove dev=30# rmdev -Rdl hdiskpower30
