Fast writes can be configured:
At the controller level, affecting all drives in the SPARCstorage Array
At the drive level, setting fast write for an individual drive
At the tray level, through the Solstice DiskSuite GUI
When fast write is enabled, it can be saved--across power cycles--as part of the SPARCstorage Array's configuration.
If the NVRAM battery is low, missing, or has failed, then fast write is disabled on the controller.
Before enabling fast write, you must stop all I/O to the controller or disk. In particular, ensure that diskset ownership has been released because an implicit I/O stream exists while ownership of a diskset is maintained. The following procedure explains how to stop all I/O.
Use the luxadm(1M) command to enable and disable NVRAM. Refer to the luxadm(1M) man page for complete information on this command.
For VxVM cluster feature (as used with Oracle Parallel Server), you should disable NVRAM.
These are the high-level steps to enable or disable NVRAM:
Ensuring that you have a current backup of all data
Ensuring that you have root privilege
Identifying the controller or disk on which to enable or disable NVRAM
Stopping all I/O to the device
Enabling or disabling NVRAM
Bringing the device back up and resynchronizing the data
These are the detailed steps to enable or disable NVRAM.
Identify the controller, tray, or individual disk whose NVRAM is to be enabled or disabled.
You can use the luxadm(1M) command to display information for a specified controller, tray, or individual disk. For example, the following display identifies all of the disks on Controller c2.
phys-hahost1# luxadm display c2 SPARCstorage Array Configuration Controller path: /devices/iommu@f,e0000000/sbus@f,e0001000/SUNW,soc@0,0/SUNW,pln@a0000000,779a16:ctlr DEVICE STATUS TRAY 1 TRAY 2 TRAY 3 slot 1 Drive: 0,0 Drive: 2,0 Drive: 4,0 2 Drive: 0,1 Drive: 2,1 Drive: 4,1 3 NO SELECT NO SELECT NO SELECT 4 NO SELECT NO SELECT NO SELECT 5 NO SELECT NO SELECT NO SELECT 6 Drive: 1,0 Drive: 3,0 Drive: 5,0 7 Drive: 1,1 NO SELECT NO SELECT 8 NO SELECT NO SELECT NO SELECT 9 NO SELECT NO SELECT NO SELECT 10 NO SELECT NO SELECT NO SELECT CONTROLLER STATUS ... |
Stop all I/O to the affected device.
Solstice DiskSuite:
For a controller or tray, refer to the applicable steps in the procedure "How to Take a SPARCstorage Array Tray Out of Service (Solstice DiskSuite)".
For a disk, refer to the applicable steps in the procedure "How to Replace a SPARCstorage Array Disk (Solstice DiskSuite)".
VxVM:
For a controller or tray, refer to the applicable steps in the procedure "How to Take a SPARCstorage Array Tray Out of Service (VxVM)".
For a disk, refer to the applicable steps in the procedure "How to Replace a SPARCstorage Array Disk (VxVM)".
Enable or disable fast write on the controller or individual disk.
Use one of the three options to the luxadm(1M) command, depending on whether you are enabling fast write for all writes, enabling fast write only for synchronous writes, or disabling fast write.
-e enables fast write for all writes
-c enables fast write for only synchronous writes
-d disables fast write
The following example saves the NVRAM configuration across power cycles and enables fast write for all writes. See the luxadm(1M) man page for details on these options.
phys-hahost# luxadm fast_write -s -e pathname |
A confirmation appears, indicating that fast write has been enabled.
Perform the steps needed to bring the component into normal operation under Sun Cluster.
Solstice DiskSuite:
For a controller or tray, refer to the applicable steps in the procedure "How to Return a SPARCstorage Array Tray to Service (Solstice DiskSuite)".
For a disk, refer to the applicable steps in the procedure "How to Replace a SPARCstorage Array Disk (Solstice DiskSuite)".
VxVM:
For a controller or tray, refer to the applicable steps in the procedure "How to Return a SPARCstorage Array Tray to Service (VxVM)".
For a disk, refer to the applicable steps in the procedure "How to Replace a SPARCstorage Array Disk (VxVM)".