16 setting up vcs – HP Hitachi Dynamic Link Manager Software User Manual
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3. Creating an HDLM Environment
243
3.16 Setting Up VCS
When VCS is installed on an HDLM host, you can register HDLM devices, or VxVM
disk groups containing HDLM devices, as resource groups.
For details on registering resource groups, refer to the VCS documentation.
Notes
The I/O fencing function only supports the configurations shown in
Table 3-33: Configurations that support the I/O fencing function.
Table 3-33: Configurations that support the I/O fencing function
#
Configurations that use volume groups are not supported.
When using the
vxfentsthdw
command of the I/O fencing function to test
HDLM devices, make sure that among all nodes, there is only one path to the
HDLM devices that are to be tested that is online. Use the HDLM command
offline
operation to change the status of other paths to offline, and then test the
devices. If there are any nodes that have more than one online path, the
vxfentsthdw
command will end abnormally.
When using the VCS I/O fencing function, we recommend that you enable the
HDLM path health checking function with a one-minute checking interval.
In addition, use the following formula to calculate the minimum value to be set
for OfflineTimeout of the DiskGroup resource that is specified for the disk group
that has used an HDLM device:
value-to-be-set = a + ((b - 1) (c + 0.5
(d - 1)))
a: The checking interval for the HDLM path health checking function
b: The number of paths for each HDLM device
#1
c: The I/O timeout value for the
sd
or
ssd
driver
#2
d: The total number of all HDLM devices
#1
OS
VCS
Storage system
Service group
Solaris 9
4.1 MP2 or later
Hitachi USP, Universal
Storage Platform V/VM or
Virtual Storage Platform
Failover service group
Solaris 10
5.0 MP1 or later
Failover service group
#
Parallel service group