Fujitsu Siemens Computers SPARC Enterprise M8000 - Manual (Page 41)

Chapter 2 What You Must Know Before Using DR 2-9
Deleting or moving a user memory board fails if either of the following statements is
true:
■ The swap area does not have sufficient free space to save data from the user
memory to be deleted.
■ There are too many locked or ISM pages to be covered by the memory on other
system boards.
2.1.1.3 I/O Device
(1) Adding an I/O Device
The device driver processing executed by the Solaris OS is based on the premise that
all device drivers dynamically recognize newly added devices. In the domain where
DR is performed, all device drivers must support the addition of devices by DR.
Upon the addition of an I/O device by DR, the I/O device is reconfigured
automatically.
The path name of a device file under /dev is configured as the path name of the
newly added I/O device to make the I/O device accessible.
(2) Deleting an I/O Device
An I/O device can be deleted when both of the following conditions are met:
■ The device to be deleted is not in use in the domain where the DR operation is to
be performed.
■ The device drivers in the domain where the DR operation is to be performed
support DR.
In most cases the device to be deleted is in use. For example, the root file system or
any other file systems requisite for operation cannot be unmounted.
To solve this problem, you can configure the system by using redundant
configuration software to make the access path to each requisite I/O device
redundant. For a disk drive unit, you can make the unit redundant by using disk
mirroring software.
If a device driver that does not support DR is used in the domain, all access to I/O
devices controlled by the device driver must be stopped, and the device driver must
be unloaded by using the modunload(1M) command.