Based on kernel version 4.13.3. Page generated on 2017-09-23 13:54 EST.
1 This driver is for Compaq's SMART Array Controllers. 2 3 Supported Cards: 4 ---------------- 5 6 This driver is known to work with the following cards: 7 8 * SA 5300 9 * SA 5i 10 * SA 532 11 * SA 5312 12 * SA 641 13 * SA 642 14 * SA 6400 15 * SA 6400 U320 Expansion Module 16 * SA 6i 17 * SA P600 18 * SA P800 19 * SA E400 20 * SA P400i 21 * SA E200 22 * SA E200i 23 * SA E500 24 * SA P700m 25 * SA P212 26 * SA P410 27 * SA P410i 28 * SA P411 29 * SA P812 30 * SA P712m 31 * SA P711m 32 33 Detecting drive failures: 34 ------------------------- 35 36 To get the status of logical volumes and to detect physical drive 37 failures, you can use the cciss_vol_status program found here: 38 http://cciss.sourceforge.net/#cciss_utils 39 40 Device Naming: 41 -------------- 42 43 If nodes are not already created in the /dev/cciss directory, run as root: 44 45 # cd /dev 46 # ./MAKEDEV cciss 47 48 You need some entries in /dev for the cciss device. The MAKEDEV script 49 can make device nodes for you automatically. Currently the device setup 50 is as follows: 51 52 Major numbers: 53 104 cciss0 54 105 cciss1 55 106 cciss2 56 105 cciss3 57 108 cciss4 58 109 cciss5 59 110 cciss6 60 111 cciss7 61 62 Minor numbers: 63 b7 b6 b5 b4 b3 b2 b1 b0 64 |----+----| |----+----| 65 | | 66 | +-------- Partition ID (0=wholedev, 1-15 partition) 67 | 68 +-------------------- Logical Volume number 69 70 The device naming scheme is: 71 /dev/cciss/c0d0 Controller 0, disk 0, whole device 72 /dev/cciss/c0d0p1 Controller 0, disk 0, partition 1 73 /dev/cciss/c0d0p2 Controller 0, disk 0, partition 2 74 /dev/cciss/c0d0p3 Controller 0, disk 0, partition 3 75 76 /dev/cciss/c1d1 Controller 1, disk 1, whole device 77 /dev/cciss/c1d1p1 Controller 1, disk 1, partition 1 78 /dev/cciss/c1d1p2 Controller 1, disk 1, partition 2 79 /dev/cciss/c1d1p3 Controller 1, disk 1, partition 3 80 81 CCISS simple mode support 82 ------------------------- 83 84 The "cciss_simple_mode=1" boot parameter may be used to prevent the driver 85 from putting the controller into "performant" mode. The difference is that 86 with simple mode, each command completion requires an interrupt, while with 87 "performant mode" (the default, and ordinarily better performing) it is 88 possible to have multiple command completions indicated by a single 89 interrupt. 90 91 SCSI tape drive and medium changer support 92 ------------------------------------------ 93 94 SCSI sequential access devices and medium changer devices are supported and 95 appropriate device nodes are automatically created. (e.g. 96 /dev/st0, /dev/st1, etc. See the "st" man page for more details.) 97 You must enable "SCSI tape drive support for Smart Array 5xxx" and 98 "SCSI support" in your kernel configuration to be able to use SCSI 99 tape drives with your Smart Array 5xxx controller. 100 101 Additionally, note that the driver will engage the SCSI core at init 102 time if any tape drives or medium changers are detected. The driver may 103 also be directed to dynamically engage the SCSI core via the /proc filesystem 104 entry which the "block" side of the driver creates as 105 /proc/driver/cciss/cciss* at runtime. This is best done via a script. 106 107 For example: 108 109 for x in /proc/driver/cciss/cciss[0-9]* 110 do 111 echo "engage scsi" > $x 112 done 113 114 Once the SCSI core is engaged by the driver, it cannot be disengaged 115 (except by unloading the driver, if it happens to be linked as a module.) 116 117 Note also that if no sequential access devices or medium changers are 118 detected, the SCSI core will not be engaged by the action of the above 119 script. 120 121 Hot plug support for SCSI tape drives 122 ------------------------------------- 123 124 Hot plugging of SCSI tape drives is supported, with some caveats. 125 The cciss driver must be informed that changes to the SCSI bus 126 have been made. This may be done via the /proc filesystem. 127 For example: 128 129 echo "rescan" > /proc/scsi/cciss0/1 130 131 This causes the driver to query the adapter about changes to the 132 physical SCSI buses and/or fibre channel arbitrated loop and the 133 driver to make note of any new or removed sequential access devices 134 or medium changers. The driver will output messages indicating what 135 devices have been added or removed and the controller, bus, target and 136 lun used to address the device. It then notifies the SCSI mid layer 137 of these changes. 138 139 Note that the naming convention of the /proc filesystem entries 140 contains a number in addition to the driver name. (E.g. "cciss0" 141 instead of just "cciss" which you might expect.) 142 143 Note: ONLY sequential access devices and medium changers are presented 144 as SCSI devices to the SCSI mid layer by the cciss driver. Specifically, 145 physical SCSI disk drives are NOT presented to the SCSI mid layer. The 146 physical SCSI disk drives are controlled directly by the array controller 147 hardware and it is important to prevent the kernel from attempting to directly 148 access these devices too, as if the array controller were merely a SCSI 149 controller in the same way that we are allowing it to access SCSI tape drives. 150 151 SCSI error handling for tape drives and medium changers 152 ------------------------------------------------------- 153 154 The linux SCSI mid layer provides an error handling protocol which 155 kicks into gear whenever a SCSI command fails to complete within a 156 certain amount of time (which can vary depending on the command). 157 The cciss driver participates in this protocol to some extent. The 158 normal protocol is a four step process. First the device is told 159 to abort the command. If that doesn't work, the device is reset. 160 If that doesn't work, the SCSI bus is reset. If that doesn't work 161 the host bus adapter is reset. Because the cciss driver is a block 162 driver as well as a SCSI driver and only the tape drives and medium 163 changers are presented to the SCSI mid layer, and unlike more 164 straightforward SCSI drivers, disk i/o continues through the block 165 side during the SCSI error recovery process, the cciss driver only 166 implements the first two of these actions, aborting the command, and 167 resetting the device. Additionally, most tape drives will not oblige 168 in aborting commands, and sometimes it appears they will not even 169 obey a reset command, though in most circumstances they will. In 170 the case that the command cannot be aborted and the device cannot be 171 reset, the device will be set offline. 172 173 In the event the error handling code is triggered and a tape drive is 174 successfully reset or the tardy command is successfully aborted, the 175 tape drive may still not allow i/o to continue until some command 176 is issued which positions the tape to a known position. Typically you 177 must rewind the tape (by issuing "mt -f /dev/st0 rewind" for example) 178 before i/o can proceed again to a tape drive which was reset. 179 180 There is a cciss_tape_cmds module parameter which can be used to make cciss 181 allocate more commands for use by tape drives. Ordinarily only a few commands 182 (6) are allocated for tape drives because tape drives are slow and 183 infrequently used and the primary purpose of Smart Array controllers is to 184 act as a RAID controller for disk drives, so the vast majority of commands 185 are allocated for disk devices. However, if you have more than a few tape 186 drives attached to a smart array, the default number of commands may not be 187 enough (for example, if you have 8 tape drives, you could only rewind 6 188 at one time with the default number of commands.) The cciss_tape_cmds module 189 parameter allows more commands (up to 16 more) to be allocated for use by 190 tape drives. For example: 191 192 insmod cciss.ko cciss_tape_cmds=16 193 194 Or, as a kernel boot parameter passed in via grub: cciss.cciss_tape_cmds=8