beautypg.com

3 storage system – HP Hitachi Dynamic Link Manager Software User Manual

Page 201

background image

4. HDLM Operation

179

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.