Solstice DiskSuite/Solaris Volume Manager Configuration Example
The following example helps to explain the process for determining the number of disk drives to place in each diskset. In this example, three storage devices are used. Existing applications are run over NFS (two file systems of 5 Gbytes each) and two ORACLE databases (one 5 Gbytes and one 10 Gbytes).
The following table shows the calculations that are used to determine the number of disk drives needed in the sample configuration. In a configuration with three storage devices, you would need 28 disk drives, which would be divided as evenly as possible among each of the three storage devices. Note that the 5-Gbyte file systems were given an additional 1 Gbyte of disk space because the number of disk drives needed was rounded up.
Table B-2 Determining the Number of Disk Drives Needed for a Configuration
Use | Data | Disk Storage Needed | Disk Drives Needed |
|---|---|---|---|
nfs1 | 5 Gbytes | 3x2.1 Gbyte disks * 2 (Mirror) | 6 |
nfs2 | 5 Gbytes | 3x2.1 Gbyte disks * 2 (Mirror) | 6 |
oracle1 | 5 Gbytes | 3x2.1 Gbyte disks * 2 (Mirror) | 6 |
oracle2 | 10 Gbytes | 5x2.1 Gbyte disks * 2 (Mirror) | 10 |
The following table shows the allocation of disk drives among the two disksets and four data services.
Table B-3 Division of Disksets
Diskset | Data Services | Disk Drives | Storage Device 1 | Storage Device 2 | Storage Device 3 |
|---|---|---|---|---|---|
dg-schost-1 | nfs1, oracle1 | 12 | 4 | 4 | 4 |
dg-schost-2 | nfs2, oracle2 | 16 | 5 | 6 | 5 |
Initially, four disk drives on each storage device (a total of 12 disks) are assigned to dg-schost-1, and five or six disk drives on each (a total of 16 disks) are assigned to dg-schost-2.
No hot spare disks are assigned to either diskset. A minimum of one hot spare disk per storage device per diskset enables one drive to be hot spared, which restores full two-way mirroring.
How to Install Solstice DiskSuite Software
Note - If you used SunPlex Manager to install Solstice DiskSuite software, do not perform this procedure. Instead, go to Mirroring the Root Disk.
If you installed Solaris 9 software, do not perform this procedure. Solaris Volume Manager software is installed with Solaris 9 software. Instead, go to How to Set the Number of Metadevice or Volume Names and Disksets.
Perform this task on each node in the cluster.
Become superuser on the cluster node.
If you install from the CD-ROM, insert the Solaris 8 Software 2 of 2 CD-ROM into the CD-ROM drive on the node.
This step assumes that the Volume Management daemon vold(1M) is running and configured to manage CD-ROM devices.
Install the Solstice DiskSuite software packages in the order that is shown in the following example.
# cd /cdrom/sol_8_sparc_2/Solaris_8/EA/products/DiskSuite_4.2.1/sparc/Packages # pkgadd -d . SUNWmdr SUNWmdu [SUNWmdx] optional-pkgs
Note - If you have Solstice DiskSuite software patches to install, do not reboot after you install the Solstice DiskSuite software.
The SUNWmdr and SUNWmdu packages are required for all Solstice DiskSuite installations. The SUNWmdx package is also required for the 64-bit Solstice DiskSuite installation.
See your Solstice DiskSuite installation documentation for information about optional software packages.
If you installed from a CD-ROM, eject the CD-ROM.
Install any Solstice DiskSuite patches.
See "Patches and Required Firmware Levels" in Sun Cluster 3.1 Release Notes for the location of patches and installation instructions.
Repeat Step 1 through Step 5 on the other nodes of the cluster.
From one node of the cluster, manually populate the global-device namespace for Solstice DiskSuite.
# scgdevs
Note - The scgdevs command might return a message similar to the following:
Could not open /dev/rdsk/c0t6d0s2 to verify device id, Device busy
If the listed device is a CD-ROM device, you can safely ignore the message.
Set the number of metadevice names and disksets that are expected in the cluster.
Go to How to Set the Number of Metadevice or Volume Names and Disksets.
How to Set the Number of Metadevice or Volume Names and Disksets
Note - If you used SunPlex Manager to install Solstice DiskSuite software, do not perform this procedure. Instead, go to Mirroring the Root Disk.
This procedure describes how to determine the number of Solstice DiskSuite metadevice or Solaris Volume Manager volume names and disksets that are needed for your configuration. This procedure also describes how to modify the /kernel/drv/md.conf file to specify these numbers.
Tip - The default number of metadevice or volume names per diskset is 128, but many configurations need more than the default. Increase this number before you implement a configuration, to save administration time later.
At the same time, keep the value of the nmdfield and the md_nsets field as low as possible. Memory structures exist for all possible devices as determined by nmdand md_nsets, even if you have not created those devices. For optimal performance, keep the value of nmd and md_nsets only slightly higher than the number of metadevices or volumes you plan to use.
Have available the Disk Device Group Configurations Worksheet.
Determine the total number of disksets you expect to need in the cluster, then add one more diskset for private disk management.
The cluster can have a maximum of 32 disksets, 31 disksets for general use plus one diskset for private disk management. The default number of disksets is 4. You supply this value for the md_nsets field in Step 4.
Determine the largest metadevice or volume name you expect to need for any diskset in the cluster.
Each diskset can have a maximum of 8192 metadevice or volume names. You supply this value for the nmd field in Step 4.
Determine the quantity of metadevice or volume names you expect to need for each diskset.
If you use local metadevices or volumes, ensure that each local metadevice or volume name is unique throughout the cluster and does not use the same name as any device-ID name in the cluster.
Tip - Choose a range of numbers to use exclusively for device-ID names and a range for each node to use exclusively for its local metadevice or volume names. For example, device-ID names might use the range from d1 to d100. Local metadevices or volumes on node 1 might use names in the range from d100 to d199. And local metadevices or volumes on node 2 might use d200 to d299.
Determine the highest of the metadevice or volume names you expect to use in any diskset.
The quantity of metadevice or volume names to set is based on the metadevice or volume name value rather than on the actual quantity. For example, if your metadevice or volume names range from d950 to d1000, Solstice DiskSuite/Solaris Volume Manager software requires that you set the value at 1000 names, not 50.
On each node, become superuser and edit the /kernel/drv/md.conf file.
Caution - All cluster nodes (or cluster pairs in the cluster-pair topology) must have identical /kernel/drv/md.conf files, regardless of the number of disksets served by each node. Failure to follow this guideline can result in serious Solstice DiskSuite/Solaris Volume Manager errors and possible loss of data.
On each node, perform a reconfiguration reboot.
# touch /reconfigure # shutdown -g0 -y -i6
Changes to the /kernel/drv/md.conf file become operative after you perform a reconfiguration reboot.
Create local state database replicas.



