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ssd@port,target:partition
The ssd driver supports Fibre Channel disk devices.
The specific type of each disk is determined by the SCSI inquiry command and reading the volume label stored on block 0 of the drive. The volume label describes the disk geometry and partitioning; it must be present or the disk cannot be mounted by the system.
The block-files access the disk using the system's normal buffering mechanism and are read and written without regard to physical disk records. A "raw" interface provides for direct transmission between the disk and the read or write buffer. A single read or write call usually results in one I/O operation; raw I/O is therefore more efficient when many bytes are transmitted. Block file names are found in /dev/dsk; the names of the raw files are found in /dev/rdsk.
I/O requests (such as lseek(2)) to the SCSI disk must have an offset that is a multiple of 512 bytes (DEV_BSIZE), or the driver returns an EINVAL error. If the transfer length is not a multiple of 512 bytes, the transfer count is rounded up by the driver.
Partition 0 is normally used for the root file system on a disk, with partition 1 as a paging area (for example, swap). Partition 2 is used to back up the entire disk. Partition 2 normally maps the entire disk and may also be used as the mount point for secondary disks in the system. The rest of the disk is normally partition 6. For the primary disk, the user file system is located here.
The device has associated error statistics. These must include counters for hard errors, soft errors and transport errors. Other data may be implemented as required.
The device maintains I/O statistics for the device and for partitions allocated for that device. For each device/partition, the driver accumulates reads, writes, bytes read, and bytes written. The driver also initiates hi-resolution time stamps at queue entry and exit points to enable monitoring of residence time and cumulative residence-length product for each queue.
Not all device drivers make per-partition IO statistics available for reporting. ssd and sd(7D) per-partition statistics are enabled by default but may be disabled in their configuration files.
Refer to dkio(7I).
EACCES
Permission denied.
EBUSY
The partition was opened exclusively by another thread.
EFAULT
The argument was a bad address.
EINVAL
Invalid argument.
EIO
An I/O error occurred.
ENOTTY
The device does not support the requested ioctl function.
ENXIO
When returned during open(2), this error indicates the device does not exist.
EROFS
The device is a read-only device.
You configure the ssd driver by defining properties in the ssd.conf file. The ssd driver supports the following properties:
enable-partition-kstats
The default value is 1, which causes partition IO statistics to be maintained. Set this value to zero to prevent the driver from recording partition statistics. This slightly reduces the CPU overhead for IO, mimimizes the amount of sar(1) data collected and makes these statistics unavailable for reporting by iostat(1M) even though the -p/-P option is specified. Regardless of this setting, disk IO statistics are always maintained.
In addition to the above properties, some device-specific tunables can be configured in ssd.conf using the 'ssd-config-list' global property. The value of this property is a list of duplets. The formal syntax is:
ssd-config-list = <duplet> [, <duplet> ]* ; where <duplet>:= "<vid+pid>" , "<tunable-list>" and <tunable-list>:= <tunable> [, <tunable> ]*; <tunable> = <name> : <value> The <vid+pid> is the string that is returned by the target device on a SCSI inquiry command. The <tunable-list> contains one or more tunables to apply to all target devices with the specified <vid+pid>. Each <tunable> is a <name> : <value> pair. Supported tunable names are: delay-busy: when busy, nsecs of delay before retry. retries-timeout: retries to perform on an IO timeout.
The following is an example of a global ssd-config-list property: ssd-config-list = "SUN T4", "delay-busy:600, retries-timeout:6", "SUN StorEdge_3510", "retries-timeout:3";
Driver configuration file
block files
raw files
cn
is the controller number on the system.
tn
7-bit disk loop identifier, such as switch setting
dn
SCSI lun n
sn
partition n (0-7)
sar(1), format(1M), iostat(1M), ioctl(2), lseek(2), open(2), read(2), write(2), scsi(4)driver.conf(4), cdio(7I), dkio(7I)
ANSI Small Computer System Interface-2 (SCSI-2)
ANSI X3.272-1996, Fibre Channel Arbitrated Loop (FC-AL)
Fibre Channel - Private Loop SCSI Direct Attach (FC-PLDA)
Error for command '<command name>' Error Level: Fatal Requested Block <n>, Error Block: <m>, Sense Key: <sense key name>, Vendor '<vendor name>': ASC = 0x<a> (<ASC name>), ASCQ = 0x<b>, FRU = 0x<c>
The command indicated by <command name> failed. The Requested Block is the block where the transfer started and the Error Block is the block that caused the error. Sense Key, ASC, and ASCQ information is returned by the target in response to a request sense command.
Check Condition on REQUEST SENSE
A REQUEST SENSE command completed with a check condition. The original command will be retried a number of times.
Label says <m> blocks Drive says <n> blocks
There is a discrepancy between the label and what the drive returned on the READ CAPACITY command.
Not enough sense information
The request sense data was less than expected.
Request Sense couldn't get sense data
The REQUEST SENSE command did not transfer any data.
Reservation Conflict
The drive was reserved by another initiator.
SCSI transport failed: reason 'xxxx' : {retrying|giving up}
The host adapter has failed to transport a command to the target for the reason stated. The driver will either retry the command or, ultimately, give up.
Unhandled Sense Key <n>
The REQUEST SENSE data included an invalid sense key.
Unit not Ready. Additional sense code 0x<n>
The drive is not ready.
corrupt label - bad geometry
The disk label is corrupted.
corrupt label - label checksum failed
The disk label is corrupted.
corrupt label - wrong magic number
The disk label is corrupted.
device busy too long
The drive returned busy during a number of retries.
disk not responding to selection
The drive was probably powered down or died.
i/o to invalid geometry
The geometry of the drive could not be established.
incomplete read/write - retrying/giving up
There was a residue after the command completed normally.
logical unit not ready
The drive is not ready.
no bp for disk label
A bp with consistent memory could not be allocated.
no mem for property
Free memory pool exhausted.
no memory for disk label
Free memory pool exhausted.
no resources for dumping
A packet could not be allocated during dumping.
offline
Drive went offline; probably powered down.
requeue of command fails<n>
Driver attempted to retry a command and experienced a transport error.
ssdrestart transport failed <n>
Driver attempted to retry a command and experienced a transport error.
transfer length not modulo <n>
Illegal request size.
transport rejected <n>
Host adapter driver was unable to accept a command.
unable to read label
Failure to read disk label.
unit does not respond to selection
Drive went offline; probably powered down.