* SA P600
* SA P800
* SA E400
- * SA E300
+ * SA P400i
+ * SA E200
+ * SA E200i
+ * SA E500
+ * SA P212
+ * SA P410
+ * SA P410i
+ * SA P411
+ * SA P812
+
+Detecting drive failures:
+-------------------------
+
+To get the status of logical volumes and to detect physical drive
+failures, you can use the cciss_vol_status program found here:
+http://cciss.sourceforge.net/#cciss_utils
+
+Device Naming:
+--------------
If nodes are not already created in the /dev/cciss directory, run as root:
# cd /dev
# ./MAKEDEV cciss
-Device Naming:
---------------
-
You need some entries in /dev for the cciss device. The MAKEDEV script
can make device nodes for you automatically. Currently the device setup
is as follows:
the SCSI core may not yet be initialized (because the driver is a block
driver) and attempting to register it with the SCSI core in such a case
would cause a hang. This is best done via an initialization script
-(typically in /etc/init.d, but could vary depending on distibution).
+(typically in /etc/init.d, but could vary depending on distribution).
For example:
for x in /proc/driver/cciss/cciss[0-9]*
Hot plugging of SCSI tape drives is supported, with some caveats.
The cciss driver must be informed that changes to the SCSI bus
-have been made, in addition to and prior to informing the SCSI
-mid layer. This may be done via the /proc filesystem. For example:
+have been made. This may be done via the /proc filesystem.
+For example:
echo "rescan" > /proc/scsi/cciss0/1
-This causes the adapter to query the adapter about changes to the
-physical SCSI buses and/or fibre channel arbitrated loop and the
+This causes the driver to query the adapter about changes to the
+physical SCSI buses and/or fibre channel arbitrated loop and the
driver to make note of any new or removed sequential access devices
or medium changers. The driver will output messages indicating what
devices have been added or removed and the controller, bus, target and
-lun used to address the device. Once this is done, the SCSI mid layer
-can be informed of changes to the virtual SCSI bus which the driver
-presents to it in the usual way. For example:
-
- echo scsi add-single-device 3 2 1 0 > /proc/scsi/scsi
-
-to add a device on controller 3, bus 2, target 1, lun 0. Note that
-the driver makes an effort to preserve the devices positions
-in the virtual SCSI bus, so if you are only moving tape drives
-around on the same adapter and not adding or removing tape drives
-from the adapter, informing the SCSI mid layer may not be necessary.
+lun used to address the device. It then notifies the SCSI mid layer
+of these changes.
Note that the naming convention of the /proc filesystem entries
contains a number in addition to the driver name. (E.g. "cciss0"
access these devices too, as if the array controller were merely a SCSI
controller in the same way that we are allowing it to access SCSI tape drives.
+SCSI error handling for tape drives and medium changers
+-------------------------------------------------------
+
+The linux SCSI mid layer provides an error handling protocol which
+kicks into gear whenever a SCSI command fails to complete within a
+certain amount of time (which can vary depending on the command).
+The cciss driver participates in this protocol to some extent. The
+normal protocol is a four step process. First the device is told
+to abort the command. If that doesn't work, the device is reset.
+If that doesn't work, the SCSI bus is reset. If that doesn't work
+the host bus adapter is reset. Because the cciss driver is a block
+driver as well as a SCSI driver and only the tape drives and medium
+changers are presented to the SCSI mid layer, and unlike more
+straightforward SCSI drivers, disk i/o continues through the block
+side during the SCSI error recovery process, the cciss driver only
+implements the first two of these actions, aborting the command, and
+resetting the device. Additionally, most tape drives will not oblige
+in aborting commands, and sometimes it appears they will not even
+obey a reset command, though in most circumstances they will. In
+the case that the command cannot be aborted and the device cannot be
+reset, the device will be set offline.
+
+In the event the error handling code is triggered and a tape drive is
+successfully reset or the tardy command is successfully aborted, the
+tape drive may still not allow i/o to continue until some command
+is issued which positions the tape to a known position. Typically you
+must rewind the tape (by issuing "mt -f /dev/st0 rewind" for example)
+before i/o can proceed again to a tape drive which was reset.
+
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff