Hitachi Dynamic Link Manager Software Users Guide for AIX (6.6) (T5208-96010, April 2011)

4. HDLM Operation
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message, you can suspend the command.
4.1.3 Storage System
 Start up the storage system before you start up the hosts, so that AIX can detect
the storage system.
 To delete an LU from the storage system, you must delete the hdisk first, and then
you can delete the LU.
 If you change the storage system's owner controller for the LU, you must
re-configure the hdisk or restart the server.
4.1.4 Notes on Shutting Down a Host
When a cluster environment is not being used and you shut down a host without
inactivating a volume group that satisfies all of the following conditions, other hosts
will no longer be able to operate the volume group:
• The volume group was created by an LU shared by multiple hosts
• The reservation policy for the LU used to configure the volume group was set to
PR_exclusive
Before shutting down a host, execute the following command to inactivate the volume
group:
# varyoffvg
volume-group-name
If you shut down the volume group without inactivating it, restart the host, activate and
then inactivate the volume group.
4.1.5 Notes on Errors in a Host
If a cluster environment is not being used and an error occurs on a host where the
reservation policy is set to
PR_exclusive in order to exclusively use an LU, other
hosts are no longer able to access the LU. In such a case, execute the
dlmpr utility to
clear the HDLM persistent reservation.
For details about the
dlmpr utility, see 7.9 dlmpr Utility for Clearing HDLM
Persistent Reservation.
While you are performing direct access operations by specifying the hdisk recognized
as an HDLM management-target device, I/O might fail if you perform the operation
below. Before performing this operation, you should make sure that the volume group
is inactive, then perform the direct access operation by specifying the hdisk recognized
as an HDLM management-target device that is not being used.
• Using the
dlmpr utility to clear the reserve key.