HP Hitachi Dynamic Link Manager Software User Manual
Page 116
3. Creating an HDLM Environment
94
3.4 Notes on Creating an HDLM Environment
This section gives points to be noted when creating an HDLM environment.
For points to be noted during operation of HDLM, see 4.1 Notes on Using HDLM.
3.4.1 Notes on Hardware Settings
For details on the settings of the storage system, see storage system manual and
maintenance documentation for the storage system.
When using HBAs that can set up a binding between target IDs and
storage-system ports, you must set up the binding before installing HDLM. For
details, see the Release Notes and the HBA documentation.
Do not change the vendor ID or product ID of a storage system. If you do, HDLM
will not be able to recognize the storage system.
The I/O timeout value reported to the sd or ssd driver depends on the timeout
values for the switch and HBA.
Depending on the switch and the HBA timeout value that is set, a timeout for I/O
might take considerable time. Accordingly, switching a path or detecting a path
error may take some time. Even the path health checking function may take longer
than the checking interval set for detecting path errors.
Make sure that all HBAs that are on a single host and connected to
HDLM-managed devices are of the same type, and have the same HBA driver
version, the same firmware, and the same FCode. If you using more than one type
of HBA, paths will not be able to be switched when an error occurs.
When you change the status of FCode on the HBA or FCode version, the physical
path name of the sd or ssd device that HDLM manages might be changed. When
you change the status of FCode after HDLM is installed, make sure that the
physical path names of HDLM-managed devices have not changed. If the
physical path name has changed, execute the
dlmsetconf
utility for creating the
HDLM driver configuration definition file, and then restart the host with the
reconfiguration option specified.
In addition, when you use VxVM and remove the devices from VxVM control,
make sure that the physical path names configured in the settings file (
/etc/vx/
vxvm.exclude
) that is used to remove from VxVM control have not been
changed. If a physical path name has been changed, re-set the physical path name.
For details on the procedure for removing the devices from VxVM control, see
3.13.3 Removing Devices from VxVM.
When using Fibre Channel, make sure that the target IDs of the SCSI comply with
the HBA settings. To determine the target IDs, refer to the HBA documentation.