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ssd(7d) [bsd man page]

ssd(7D) 							      Devices								   ssd(7D)

NAME
ssd - Fibre Channel Arbitrated Loop disk device driver SYNOPSIS
ssd@port,target:partition DESCRIPTION
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 usu- ally 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. DEVICE STATISTICS SUPPORT
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. IOCTLS
Refer to dkio(7I). ERRORS
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. CONFIGURATION
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. FILES
ssd.conf Driver configuration file /dev/dsk/cntndnsn block files /dev/rdsk/cntndnsn 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) SEE ALSO
sar(1), format(1M), iostat(1M), ioctl(2), lseek(2), open(2), read(2), write(2), 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) DIAGNOSTICS
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, ulti- mately, 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. SunOS 5.10 30 May 2003 ssd(7D)

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