This section describes some things to be aware of when implementing Solaris Volume Manager software.
iostat Output Shows sd and md Devices
The iostat command is used to gather I/O performance information from the system. Solaris Volume Manager devices show up as md devices in the iostat output. In addition to Solaris Volume Manager devices, underlying disk statistics are displayed. Make sure that I/O is not accounted for multiple times when analyzing iostat output.
In the following output example, md26 is a soft partition on top of md2, and md2 is a meta device on top of ssd3. There is a total of 402.0 reads per second to the md26 meta device. The system is not performing 3*402 = 1206 reads per second.
device r/s w/s kr/s kw/s ... md2 402.0 0.0 51458.7 0.0 ... md26 402.0 0.0 51460.5 0.0 ... ssd3 402.0 0.0 51463.6 0.0 ...
Raw Device Permissions
Solaris Volume Manager software does not directly manage device permissions. You can use the chown command to change permissions, but this change is not persistent across system reboots. To make device ownership persistent, modify the /etc/minor_perm file.