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Commit | Line | Data |
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1 | Linux Driver for Mylex DAC960/AcceleRAID/eXtremeRAID PCI RAID Controllers | |
2 | ||
3 | Version 2.2.11 for Linux 2.2.19 | |
4 | Version 2.4.11 for Linux 2.4.12 | |
5 | ||
6 | PRODUCTION RELEASE | |
7 | ||
8 | 11 October 2001 | |
9 | ||
10 | Leonard N. Zubkoff | |
11 | Dandelion Digital | |
12 | lnz@dandelion.com | |
13 | ||
14 | Copyright 1998-2001 by Leonard N. Zubkoff <lnz@dandelion.com> | |
15 | ||
16 | ||
17 | INTRODUCTION | |
18 | ||
19 | Mylex, Inc. designs and manufactures a variety of high performance PCI RAID | |
20 | controllers. Mylex Corporation is located at 34551 Ardenwood Blvd., Fremont, | |
21 | California 94555, USA and can be reached at 510.796.6100 or on the World Wide | |
22 | Web at http://www.mylex.com. Mylex Technical Support can be reached by | |
23 | electronic mail at mylexsup@us.ibm.com, by voice at 510.608.2400, or by FAX at | |
24 | 510.745.7715. Contact information for offices in Europe and Japan is available | |
25 | on their Web site. | |
26 | ||
27 | The latest information on Linux support for DAC960 PCI RAID Controllers, as | |
28 | well as the most recent release of this driver, will always be available from | |
29 | my Linux Home Page at URL "http://www.dandelion.com/Linux/". The Linux DAC960 | |
30 | driver supports all current Mylex PCI RAID controllers including the new | |
31 | eXtremeRAID 2000/3000 and AcceleRAID 352/170/160 models which have an entirely | |
32 | new firmware interface from the older eXtremeRAID 1100, AcceleRAID 150/200/250, | |
33 | and DAC960PJ/PG/PU/PD/PL. See below for a complete controller list as well as | |
34 | minimum firmware version requirements. For simplicity, in most places this | |
35 | documentation refers to DAC960 generically rather than explicitly listing all | |
36 | the supported models. | |
37 | ||
38 | Driver bug reports should be sent via electronic mail to "lnz@dandelion.com". | |
39 | Please include with the bug report the complete configuration messages reported | |
40 | by the driver at startup, along with any subsequent system messages relevant to | |
41 | the controller's operation, and a detailed description of your system's | |
42 | hardware configuration. Driver bugs are actually quite rare; if you encounter | |
43 | problems with disks being marked offline, for example, please contact Mylex | |
44 | Technical Support as the problem is related to the hardware configuration | |
45 | rather than the Linux driver. | |
46 | ||
47 | Please consult the RAID controller documentation for detailed information | |
48 | regarding installation and configuration of the controllers. This document | |
49 | primarily provides information specific to the Linux support. | |
50 | ||
51 | ||
52 | DRIVER FEATURES | |
53 | ||
54 | The DAC960 RAID controllers are supported solely as high performance RAID | |
55 | controllers, not as interfaces to arbitrary SCSI devices. The Linux DAC960 | |
56 | driver operates at the block device level, the same level as the SCSI and IDE | |
57 | drivers. Unlike other RAID controllers currently supported on Linux, the | |
58 | DAC960 driver is not dependent on the SCSI subsystem, and hence avoids all the | |
59 | complexity and unnecessary code that would be associated with an implementation | |
60 | as a SCSI driver. The DAC960 driver is designed for as high a performance as | |
61 | possible with no compromises or extra code for compatibility with lower | |
62 | performance devices. The DAC960 driver includes extensive error logging and | |
63 | online configuration management capabilities. Except for initial configuration | |
64 | of the controller and adding new disk drives, most everything can be handled | |
65 | from Linux while the system is operational. | |
66 | ||
67 | The DAC960 driver is architected to support up to 8 controllers per system. | |
68 | Each DAC960 parallel SCSI controller can support up to 15 disk drives per | |
69 | channel, for a maximum of 60 drives on a four channel controller; the fibre | |
70 | channel eXtremeRAID 3000 controller supports up to 125 disk drives per loop for | |
71 | a total of 250 drives. The drives installed on a controller are divided into | |
72 | one or more "Drive Groups", and then each Drive Group is subdivided further | |
73 | into 1 to 32 "Logical Drives". Each Logical Drive has a specific RAID Level | |
74 | and caching policy associated with it, and it appears to Linux as a single | |
75 | block device. Logical Drives are further subdivided into up to 7 partitions | |
76 | through the normal Linux and PC disk partitioning schemes. Logical Drives are | |
77 | also known as "System Drives", and Drive Groups are also called "Packs". Both | |
78 | terms are in use in the Mylex documentation; I have chosen to standardize on | |
79 | the more generic "Logical Drive" and "Drive Group". | |
80 | ||
81 | DAC960 RAID disk devices are named in the style of the Device File System | |
82 | (DEVFS). The device corresponding to Logical Drive D on Controller C is | |
83 | referred to as /dev/rd/cCdD, and the partitions are called /dev/rd/cCdDp1 | |
84 | through /dev/rd/cCdDp7. For example, partition 3 of Logical Drive 5 on | |
85 | Controller 2 is referred to as /dev/rd/c2d5p3. Note that unlike with SCSI | |
86 | disks the device names will not change in the event of a disk drive failure. | |
87 | The DAC960 driver is assigned major numbers 48 - 55 with one major number per | |
88 | controller. The 8 bits of minor number are divided into 5 bits for the Logical | |
89 | Drive and 3 bits for the partition. | |
90 | ||
91 | ||
92 | SUPPORTED DAC960/AcceleRAID/eXtremeRAID PCI RAID CONTROLLERS | |
93 | ||
94 | The following list comprises the supported DAC960, AcceleRAID, and eXtremeRAID | |
95 | PCI RAID Controllers as of the date of this document. It is recommended that | |
96 | anyone purchasing a Mylex PCI RAID Controller not in the following table | |
97 | contact the author beforehand to verify that it is or will be supported. | |
98 | ||
99 | eXtremeRAID 3000 | |
100 | 1 Wide Ultra-2/LVD SCSI channel | |
101 | 2 External Fibre FC-AL channels | |
102 | 233MHz StrongARM SA 110 Processor | |
103 | 64 Bit 33MHz PCI (backward compatible with 32 Bit PCI slots) | |
104 | 32MB/64MB ECC SDRAM Memory | |
105 | ||
106 | eXtremeRAID 2000 | |
107 | 4 Wide Ultra-160 LVD SCSI channels | |
108 | 233MHz StrongARM SA 110 Processor | |
109 | 64 Bit 33MHz PCI (backward compatible with 32 Bit PCI slots) | |
110 | 32MB/64MB ECC SDRAM Memory | |
111 | ||
112 | AcceleRAID 352 | |
113 | 2 Wide Ultra-160 LVD SCSI channels | |
114 | 100MHz Intel i960RN RISC Processor | |
115 | 64 Bit 33MHz PCI (backward compatible with 32 Bit PCI slots) | |
116 | 32MB/64MB ECC SDRAM Memory | |
117 | ||
118 | AcceleRAID 170 | |
119 | 1 Wide Ultra-160 LVD SCSI channel | |
120 | 100MHz Intel i960RM RISC Processor | |
121 | 16MB/32MB/64MB ECC SDRAM Memory | |
122 | ||
123 | AcceleRAID 160 (AcceleRAID 170LP) | |
124 | 1 Wide Ultra-160 LVD SCSI channel | |
125 | 100MHz Intel i960RS RISC Processor | |
126 | Built in 16M ECC SDRAM Memory | |
127 | PCI Low Profile Form Factor - fit for 2U height | |
128 | ||
129 | eXtremeRAID 1100 (DAC1164P) | |
130 | 3 Wide Ultra-2/LVD SCSI channels | |
131 | 233MHz StrongARM SA 110 Processor | |
132 | 64 Bit 33MHz PCI (backward compatible with 32 Bit PCI slots) | |
133 | 16MB/32MB/64MB Parity SDRAM Memory with Battery Backup | |
134 | ||
135 | AcceleRAID 250 (DAC960PTL1) | |
136 | Uses onboard Symbios SCSI chips on certain motherboards | |
137 | Also includes one onboard Wide Ultra-2/LVD SCSI Channel | |
138 | 66MHz Intel i960RD RISC Processor | |
139 | 4MB/8MB/16MB/32MB/64MB/128MB ECC EDO Memory | |
140 | ||
141 | AcceleRAID 200 (DAC960PTL0) | |
142 | Uses onboard Symbios SCSI chips on certain motherboards | |
143 | Includes no onboard SCSI Channels | |
144 | 66MHz Intel i960RD RISC Processor | |
145 | 4MB/8MB/16MB/32MB/64MB/128MB ECC EDO Memory | |
146 | ||
147 | AcceleRAID 150 (DAC960PRL) | |
148 | Uses onboard Symbios SCSI chips on certain motherboards | |
149 | Also includes one onboard Wide Ultra-2/LVD SCSI Channel | |
150 | 33MHz Intel i960RP RISC Processor | |
151 | 4MB Parity EDO Memory | |
152 | ||
153 | DAC960PJ 1/2/3 Wide Ultra SCSI-3 Channels | |
154 | 66MHz Intel i960RD RISC Processor | |
155 | 4MB/8MB/16MB/32MB/64MB/128MB ECC EDO Memory | |
156 | ||
157 | DAC960PG 1/2/3 Wide Ultra SCSI-3 Channels | |
158 | 33MHz Intel i960RP RISC Processor | |
159 | 4MB/8MB ECC EDO Memory | |
160 | ||
161 | DAC960PU 1/2/3 Wide Ultra SCSI-3 Channels | |
162 | Intel i960CF RISC Processor | |
163 | 4MB/8MB EDRAM or 2MB/4MB/8MB/16MB/32MB DRAM Memory | |
164 | ||
165 | DAC960PD 1/2/3 Wide Fast SCSI-2 Channels | |
166 | Intel i960CF RISC Processor | |
167 | 4MB/8MB EDRAM or 2MB/4MB/8MB/16MB/32MB DRAM Memory | |
168 | ||
169 | DAC960PL 1/2/3 Wide Fast SCSI-2 Channels | |
170 | Intel i960 RISC Processor | |
171 | 2MB/4MB/8MB/16MB/32MB DRAM Memory | |
172 | ||
173 | DAC960P 1/2/3 Wide Fast SCSI-2 Channels | |
174 | Intel i960 RISC Processor | |
175 | 2MB/4MB/8MB/16MB/32MB DRAM Memory | |
176 | ||
177 | For the eXtremeRAID 2000/3000 and AcceleRAID 352/170/160, firmware version | |
178 | 6.00-01 or above is required. | |
179 | ||
180 | For the eXtremeRAID 1100, firmware version 5.06-0-52 or above is required. | |
181 | ||
182 | For the AcceleRAID 250, 200, and 150, firmware version 4.06-0-57 or above is | |
183 | required. | |
184 | ||
185 | For the DAC960PJ and DAC960PG, firmware version 4.06-0-00 or above is required. | |
186 | ||
187 | For the DAC960PU, DAC960PD, DAC960PL, and DAC960P, either firmware version | |
188 | 3.51-0-04 or above is required (for dual Flash ROM controllers), or firmware | |
189 | version 2.73-0-00 or above is required (for single Flash ROM controllers) | |
190 | ||
191 | Please note that not all SCSI disk drives are suitable for use with DAC960 | |
192 | controllers, and only particular firmware versions of any given model may | |
193 | actually function correctly. Similarly, not all motherboards have a BIOS that | |
194 | properly initializes the AcceleRAID 250, AcceleRAID 200, AcceleRAID 150, | |
195 | DAC960PJ, and DAC960PG because the Intel i960RD/RP is a multi-function device. | |
196 | If in doubt, contact Mylex RAID Technical Support (mylexsup@us.ibm.com) to | |
197 | verify compatibility. Mylex makes available a hard disk compatibility list at | |
198 | http://www.mylex.com/support/hdcomp/hd-lists.html. | |
199 | ||
200 | ||
201 | DRIVER INSTALLATION | |
202 | ||
203 | This distribution was prepared for Linux kernel version 2.2.19 or 2.4.12. | |
204 | ||
205 | To install the DAC960 RAID driver, you may use the following commands, | |
206 | replacing "/usr/src" with wherever you keep your Linux kernel source tree: | |
207 | ||
208 | cd /usr/src | |
209 | tar -xvzf DAC960-2.2.11.tar.gz (or DAC960-2.4.11.tar.gz) | |
210 | mv README.DAC960 linux/Documentation | |
211 | mv DAC960.[ch] linux/drivers/block | |
212 | patch -p0 < DAC960.patch (if DAC960.patch is included) | |
213 | cd linux | |
214 | make config | |
215 | make bzImage (or zImage) | |
216 | ||
217 | Then install "arch/i386/boot/bzImage" or "arch/i386/boot/zImage" as your | |
218 | standard kernel, run lilo if appropriate, and reboot. | |
219 | ||
220 | To create the necessary devices in /dev, the "make_rd" script included in | |
221 | "DAC960-Utilities.tar.gz" from http://www.dandelion.com/Linux/ may be used. | |
222 | LILO 21 and FDISK v2.9 include DAC960 support; also included in this archive | |
223 | are patches to LILO 20 and FDISK v2.8 that add DAC960 support, along with | |
224 | statically linked executables of LILO and FDISK. This modified version of LILO | |
225 | will allow booting from a DAC960 controller and/or mounting the root file | |
226 | system from a DAC960. | |
227 | ||
228 | Red Hat Linux 6.0 and SuSE Linux 6.1 include support for Mylex PCI RAID | |
229 | controllers. Installing directly onto a DAC960 may be problematic from other | |
230 | Linux distributions until their installation utilities are updated. | |
231 | ||
232 | ||
233 | INSTALLATION NOTES | |
234 | ||
235 | Before installing Linux or adding DAC960 logical drives to an existing Linux | |
236 | system, the controller must first be configured to provide one or more logical | |
237 | drives using the BIOS Configuration Utility or DACCF. Please note that since | |
238 | there are only at most 6 usable partitions on each logical drive, systems | |
239 | requiring more partitions should subdivide a drive group into multiple logical | |
240 | drives, each of which can have up to 6 usable partitions. Also, note that with | |
241 | large disk arrays it is advisable to enable the 8GB BIOS Geometry (255/63) | |
242 | rather than accepting the default 2GB BIOS Geometry (128/32); failing to so do | |
243 | will cause the logical drive geometry to have more than 65535 cylinders which | |
244 | will make it impossible for FDISK to be used properly. The 8GB BIOS Geometry | |
245 | can be enabled by configuring the DAC960 BIOS, which is accessible via Alt-M | |
246 | during the BIOS initialization sequence. | |
247 | ||
248 | For maximum performance and the most efficient E2FSCK performance, it is | |
249 | recommended that EXT2 file systems be built with a 4KB block size and 16 block | |
250 | stride to match the DAC960 controller's 64KB default stripe size. The command | |
251 | "mke2fs -b 4096 -R stride=16 <device>" is appropriate. Unless there will be a | |
252 | large number of small files on the file systems, it is also beneficial to add | |
253 | the "-i 16384" option to increase the bytes per inode parameter thereby | |
254 | reducing the file system metadata. Finally, on systems that will only be run | |
255 | with Linux 2.2 or later kernels it is beneficial to enable sparse superblocks | |
256 | with the "-s 1" option. | |
257 | ||
258 | ||
259 | DAC960 ANNOUNCEMENTS MAILING LIST | |
260 | ||
261 | The DAC960 Announcements Mailing List provides a forum for informing Linux | |
262 | users of new driver releases and other announcements regarding Linux support | |
263 | for DAC960 PCI RAID Controllers. To join the mailing list, send a message to | |
264 | "dac960-announce-request@dandelion.com" with the line "subscribe" in the | |
265 | message body. | |
266 | ||
267 | ||
268 | CONTROLLER CONFIGURATION AND STATUS MONITORING | |
269 | ||
270 | The DAC960 RAID controllers running firmware 4.06 or above include a Background | |
271 | Initialization facility so that system downtime is minimized both for initial | |
272 | installation and subsequent configuration of additional storage. The BIOS | |
273 | Configuration Utility (accessible via Alt-R during the BIOS initialization | |
274 | sequence) is used to quickly configure the controller, and then the logical | |
275 | drives that have been created are available for immediate use even while they | |
276 | are still being initialized by the controller. The primary need for online | |
277 | configuration and status monitoring is then to avoid system downtime when disk | |
278 | drives fail and must be replaced. Mylex's online monitoring and configuration | |
279 | utilities are being ported to Linux and will become available at some point in | |
280 | the future. Note that with a SAF-TE (SCSI Accessed Fault-Tolerant Enclosure) | |
281 | enclosure, the controller is able to rebuild failed drives automatically as | |
282 | soon as a drive replacement is made available. | |
283 | ||
284 | The primary interfaces for controller configuration and status monitoring are | |
285 | special files created in the /proc/rd/... hierarchy along with the normal | |
286 | system console logging mechanism. Whenever the system is operating, the DAC960 | |
287 | driver queries each controller for status information every 10 seconds, and | |
288 | checks for additional conditions every 60 seconds. The initial status of each | |
289 | controller is always available for controller N in /proc/rd/cN/initial_status, | |
290 | and the current status as of the last status monitoring query is available in | |
291 | /proc/rd/cN/current_status. In addition, status changes are also logged by the | |
292 | driver to the system console and will appear in the log files maintained by | |
293 | syslog. The progress of asynchronous rebuild or consistency check operations | |
294 | is also available in /proc/rd/cN/current_status, and progress messages are | |
295 | logged to the system console at most every 60 seconds. | |
296 | ||
297 | Starting with the 2.2.3/2.0.3 versions of the driver, the status information | |
298 | available in /proc/rd/cN/initial_status and /proc/rd/cN/current_status has been | |
299 | augmented to include the vendor, model, revision, and serial number (if | |
300 | available) for each physical device found connected to the controller: | |
301 | ||
302 | ***** DAC960 RAID Driver Version 2.2.3 of 19 August 1999 ***** | |
303 | Copyright 1998-1999 by Leonard N. Zubkoff <lnz@dandelion.com> | |
304 | Configuring Mylex DAC960PRL PCI RAID Controller | |
305 | Firmware Version: 4.07-0-07, Channels: 1, Memory Size: 16MB | |
306 | PCI Bus: 1, Device: 4, Function: 1, I/O Address: Unassigned | |
307 | PCI Address: 0xFE300000 mapped at 0xA0800000, IRQ Channel: 21 | |
308 | Controller Queue Depth: 128, Maximum Blocks per Command: 128 | |
309 | Driver Queue Depth: 127, Maximum Scatter/Gather Segments: 33 | |
310 | Stripe Size: 64KB, Segment Size: 8KB, BIOS Geometry: 255/63 | |
311 | SAF-TE Enclosure Management Enabled | |
312 | Physical Devices: | |
313 | 0:0 Vendor: IBM Model: DRVS09D Revision: 0270 | |
314 | Serial Number: 68016775HA | |
315 | Disk Status: Online, 17928192 blocks | |
316 | 0:1 Vendor: IBM Model: DRVS09D Revision: 0270 | |
317 | Serial Number: 68004E53HA | |
318 | Disk Status: Online, 17928192 blocks | |
319 | 0:2 Vendor: IBM Model: DRVS09D Revision: 0270 | |
320 | Serial Number: 13013935HA | |
321 | Disk Status: Online, 17928192 blocks | |
322 | 0:3 Vendor: IBM Model: DRVS09D Revision: 0270 | |
323 | Serial Number: 13016897HA | |
324 | Disk Status: Online, 17928192 blocks | |
325 | 0:4 Vendor: IBM Model: DRVS09D Revision: 0270 | |
326 | Serial Number: 68019905HA | |
327 | Disk Status: Online, 17928192 blocks | |
328 | 0:5 Vendor: IBM Model: DRVS09D Revision: 0270 | |
329 | Serial Number: 68012753HA | |
330 | Disk Status: Online, 17928192 blocks | |
331 | 0:6 Vendor: ESG-SHV Model: SCA HSBP M6 Revision: 0.61 | |
332 | Logical Drives: | |
333 | /dev/rd/c0d0: RAID-5, Online, 89640960 blocks, Write Thru | |
334 | No Rebuild or Consistency Check in Progress | |
335 | ||
336 | To simplify the monitoring process for custom software, the special file | |
337 | /proc/rd/status returns "OK" when all DAC960 controllers in the system are | |
338 | operating normally and no failures have occurred, or "ALERT" if any logical | |
339 | drives are offline or critical or any non-standby physical drives are dead. | |
340 | ||
341 | Configuration commands for controller N are available via the special file | |
342 | /proc/rd/cN/user_command. A human readable command can be written to this | |
343 | special file to initiate a configuration operation, and the results of the | |
344 | operation can then be read back from the special file in addition to being | |
345 | logged to the system console. The shell command sequence | |
346 | ||
347 | echo "<configuration-command>" > /proc/rd/c0/user_command | |
348 | cat /proc/rd/c0/user_command | |
349 | ||
350 | is typically used to execute configuration commands. The configuration | |
351 | commands are: | |
352 | ||
353 | flush-cache | |
354 | ||
355 | The "flush-cache" command flushes the controller's cache. The system | |
356 | automatically flushes the cache at shutdown or if the driver module is | |
357 | unloaded, so this command is only needed to be certain a write back cache | |
358 | is flushed to disk before the system is powered off by a command to a UPS. | |
359 | Note that the flush-cache command also stops an asynchronous rebuild or | |
360 | consistency check, so it should not be used except when the system is being | |
361 | halted. | |
362 | ||
363 | kill <channel>:<target-id> | |
364 | ||
365 | The "kill" command marks the physical drive <channel>:<target-id> as DEAD. | |
366 | This command is provided primarily for testing, and should not be used | |
367 | during normal system operation. | |
368 | ||
369 | make-online <channel>:<target-id> | |
370 | ||
371 | The "make-online" command changes the physical drive <channel>:<target-id> | |
372 | from status DEAD to status ONLINE. In cases where multiple physical drives | |
373 | have been killed simultaneously, this command may be used to bring all but | |
374 | one of them back online, after which a rebuild to the final drive is | |
375 | necessary. | |
376 | ||
377 | Warning: make-online should only be used on a dead physical drive that is | |
378 | an active part of a drive group, never on a standby drive. The command | |
379 | should never be used on a dead drive that is part of a critical logical | |
380 | drive; rebuild should be used if only a single drive is dead. | |
381 | ||
382 | make-standby <channel>:<target-id> | |
383 | ||
384 | The "make-standby" command changes physical drive <channel>:<target-id> | |
385 | from status DEAD to status STANDBY. It should only be used in cases where | |
386 | a dead drive was replaced after an automatic rebuild was performed onto a | |
387 | standby drive. It cannot be used to add a standby drive to the controller | |
388 | configuration if one was not created initially; the BIOS Configuration | |
389 | Utility must be used for that currently. | |
390 | ||
391 | rebuild <channel>:<target-id> | |
392 | ||
393 | The "rebuild" command initiates an asynchronous rebuild onto physical drive | |
394 | <channel>:<target-id>. It should only be used when a dead drive has been | |
395 | replaced. | |
396 | ||
397 | check-consistency <logical-drive-number> | |
398 | ||
399 | The "check-consistency" command initiates an asynchronous consistency check | |
400 | of <logical-drive-number> with automatic restoration. It can be used | |
401 | whenever it is desired to verify the consistency of the redundancy | |
402 | information. | |
403 | ||
404 | cancel-rebuild | |
405 | cancel-consistency-check | |
406 | ||
407 | The "cancel-rebuild" and "cancel-consistency-check" commands cancel any | |
408 | rebuild or consistency check operations previously initiated. | |
409 | ||
410 | ||
411 | EXAMPLE I - DRIVE FAILURE WITHOUT A STANDBY DRIVE | |
412 | ||
413 | The following annotated logs demonstrate the controller configuration and and | |
414 | online status monitoring capabilities of the Linux DAC960 Driver. The test | |
415 | configuration comprises 6 1GB Quantum Atlas I disk drives on two channels of a | |
416 | DAC960PJ controller. The physical drives are configured into a single drive | |
417 | group without a standby drive, and the drive group has been configured into two | |
418 | logical drives, one RAID-5 and one RAID-6. Note that these logs are from an | |
419 | earlier version of the driver and the messages have changed somewhat with newer | |
420 | releases, but the functionality remains similar. First, here is the current | |
421 | status of the RAID configuration: | |
422 | ||
423 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
424 | ***** DAC960 RAID Driver Version 2.0.0 of 23 March 1999 ***** | |
425 | Copyright 1998-1999 by Leonard N. Zubkoff <lnz@dandelion.com> | |
426 | Configuring Mylex DAC960PJ PCI RAID Controller | |
427 | Firmware Version: 4.06-0-08, Channels: 3, Memory Size: 8MB | |
428 | PCI Bus: 0, Device: 19, Function: 1, I/O Address: Unassigned | |
429 | PCI Address: 0xFD4FC000 mapped at 0x8807000, IRQ Channel: 9 | |
430 | Controller Queue Depth: 128, Maximum Blocks per Command: 128 | |
431 | Driver Queue Depth: 127, Maximum Scatter/Gather Segments: 33 | |
432 | Stripe Size: 64KB, Segment Size: 8KB, BIOS Geometry: 255/63 | |
433 | Physical Devices: | |
434 | 0:1 - Disk: Online, 2201600 blocks | |
435 | 0:2 - Disk: Online, 2201600 blocks | |
436 | 0:3 - Disk: Online, 2201600 blocks | |
437 | 1:1 - Disk: Online, 2201600 blocks | |
438 | 1:2 - Disk: Online, 2201600 blocks | |
439 | 1:3 - Disk: Online, 2201600 blocks | |
440 | Logical Drives: | |
441 | /dev/rd/c0d0: RAID-5, Online, 5498880 blocks, Write Thru | |
442 | /dev/rd/c0d1: RAID-6, Online, 3305472 blocks, Write Thru | |
443 | No Rebuild or Consistency Check in Progress | |
444 | ||
445 | gwynedd:/u/lnz# cat /proc/rd/status | |
446 | OK | |
447 | ||
448 | The above messages indicate that everything is healthy, and /proc/rd/status | |
449 | returns "OK" indicating that there are no problems with any DAC960 controller | |
450 | in the system. For demonstration purposes, while I/O is active Physical Drive | |
451 | 1:1 is now disconnected, simulating a drive failure. The failure is noted by | |
452 | the driver within 10 seconds of the controller's having detected it, and the | |
453 | driver logs the following console status messages indicating that Logical | |
454 | Drives 0 and 1 are now CRITICAL as a result of Physical Drive 1:1 being DEAD: | |
455 | ||
456 | DAC960#0: Physical Drive 1:2 Error Log: Sense Key = 6, ASC = 29, ASCQ = 02 | |
457 | DAC960#0: Physical Drive 1:3 Error Log: Sense Key = 6, ASC = 29, ASCQ = 02 | |
458 | DAC960#0: Physical Drive 1:1 killed because of timeout on SCSI command | |
459 | DAC960#0: Physical Drive 1:1 is now DEAD | |
460 | DAC960#0: Logical Drive 0 (/dev/rd/c0d0) is now CRITICAL | |
461 | DAC960#0: Logical Drive 1 (/dev/rd/c0d1) is now CRITICAL | |
462 | ||
463 | The Sense Keys logged here are just Check Condition / Unit Attention conditions | |
464 | arising from a SCSI bus reset that is forced by the controller during its error | |
465 | recovery procedures. Concurrently with the above, the driver status available | |
466 | from /proc/rd also reflects the drive failure. The status message in | |
467 | /proc/rd/status has changed from "OK" to "ALERT": | |
468 | ||
469 | gwynedd:/u/lnz# cat /proc/rd/status | |
470 | ALERT | |
471 | ||
472 | and /proc/rd/c0/current_status has been updated: | |
473 | ||
474 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
475 | ... | |
476 | Physical Devices: | |
477 | 0:1 - Disk: Online, 2201600 blocks | |
478 | 0:2 - Disk: Online, 2201600 blocks | |
479 | 0:3 - Disk: Online, 2201600 blocks | |
480 | 1:1 - Disk: Dead, 2201600 blocks | |
481 | 1:2 - Disk: Online, 2201600 blocks | |
482 | 1:3 - Disk: Online, 2201600 blocks | |
483 | Logical Drives: | |
484 | /dev/rd/c0d0: RAID-5, Critical, 5498880 blocks, Write Thru | |
485 | /dev/rd/c0d1: RAID-6, Critical, 3305472 blocks, Write Thru | |
486 | No Rebuild or Consistency Check in Progress | |
487 | ||
488 | Since there are no standby drives configured, the system can continue to access | |
489 | the logical drives in a performance degraded mode until the failed drive is | |
490 | replaced and a rebuild operation completed to restore the redundancy of the | |
491 | logical drives. Once Physical Drive 1:1 is replaced with a properly | |
492 | functioning drive, or if the physical drive was killed without having failed | |
493 | (e.g., due to electrical problems on the SCSI bus), the user can instruct the | |
494 | controller to initiate a rebuild operation onto the newly replaced drive: | |
495 | ||
496 | gwynedd:/u/lnz# echo "rebuild 1:1" > /proc/rd/c0/user_command | |
497 | gwynedd:/u/lnz# cat /proc/rd/c0/user_command | |
498 | Rebuild of Physical Drive 1:1 Initiated | |
499 | ||
500 | The echo command instructs the controller to initiate an asynchronous rebuild | |
501 | operation onto Physical Drive 1:1, and the status message that results from the | |
502 | operation is then available for reading from /proc/rd/c0/user_command, as well | |
503 | as being logged to the console by the driver. | |
504 | ||
505 | Within 10 seconds of this command the driver logs the initiation of the | |
506 | asynchronous rebuild operation: | |
507 | ||
508 | DAC960#0: Rebuild of Physical Drive 1:1 Initiated | |
509 | DAC960#0: Physical Drive 1:1 Error Log: Sense Key = 6, ASC = 29, ASCQ = 01 | |
510 | DAC960#0: Physical Drive 1:1 is now WRITE-ONLY | |
511 | DAC960#0: Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 1% completed | |
512 | ||
513 | and /proc/rd/c0/current_status is updated: | |
514 | ||
515 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
516 | ... | |
517 | Physical Devices: | |
518 | 0:1 - Disk: Online, 2201600 blocks | |
519 | 0:2 - Disk: Online, 2201600 blocks | |
520 | 0:3 - Disk: Online, 2201600 blocks | |
521 | 1:1 - Disk: Write-Only, 2201600 blocks | |
522 | 1:2 - Disk: Online, 2201600 blocks | |
523 | 1:3 - Disk: Online, 2201600 blocks | |
524 | Logical Drives: | |
525 | /dev/rd/c0d0: RAID-5, Critical, 5498880 blocks, Write Thru | |
526 | /dev/rd/c0d1: RAID-6, Critical, 3305472 blocks, Write Thru | |
527 | Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 6% completed | |
528 | ||
529 | As the rebuild progresses, the current status in /proc/rd/c0/current_status is | |
530 | updated every 10 seconds: | |
531 | ||
532 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
533 | ... | |
534 | Physical Devices: | |
535 | 0:1 - Disk: Online, 2201600 blocks | |
536 | 0:2 - Disk: Online, 2201600 blocks | |
537 | 0:3 - Disk: Online, 2201600 blocks | |
538 | 1:1 - Disk: Write-Only, 2201600 blocks | |
539 | 1:2 - Disk: Online, 2201600 blocks | |
540 | 1:3 - Disk: Online, 2201600 blocks | |
541 | Logical Drives: | |
542 | /dev/rd/c0d0: RAID-5, Critical, 5498880 blocks, Write Thru | |
543 | /dev/rd/c0d1: RAID-6, Critical, 3305472 blocks, Write Thru | |
544 | Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 15% completed | |
545 | ||
546 | and every minute a progress message is logged to the console by the driver: | |
547 | ||
548 | DAC960#0: Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 32% completed | |
549 | DAC960#0: Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 63% completed | |
550 | DAC960#0: Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 94% completed | |
551 | DAC960#0: Rebuild in Progress: Logical Drive 1 (/dev/rd/c0d1) 94% completed | |
552 | ||
553 | Finally, the rebuild completes successfully. The driver logs the status of the | |
554 | logical and physical drives and the rebuild completion: | |
555 | ||
556 | DAC960#0: Rebuild Completed Successfully | |
557 | DAC960#0: Physical Drive 1:1 is now ONLINE | |
558 | DAC960#0: Logical Drive 0 (/dev/rd/c0d0) is now ONLINE | |
559 | DAC960#0: Logical Drive 1 (/dev/rd/c0d1) is now ONLINE | |
560 | ||
561 | /proc/rd/c0/current_status is updated: | |
562 | ||
563 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
564 | ... | |
565 | Physical Devices: | |
566 | 0:1 - Disk: Online, 2201600 blocks | |
567 | 0:2 - Disk: Online, 2201600 blocks | |
568 | 0:3 - Disk: Online, 2201600 blocks | |
569 | 1:1 - Disk: Online, 2201600 blocks | |
570 | 1:2 - Disk: Online, 2201600 blocks | |
571 | 1:3 - Disk: Online, 2201600 blocks | |
572 | Logical Drives: | |
573 | /dev/rd/c0d0: RAID-5, Online, 5498880 blocks, Write Thru | |
574 | /dev/rd/c0d1: RAID-6, Online, 3305472 blocks, Write Thru | |
575 | Rebuild Completed Successfully | |
576 | ||
577 | and /proc/rd/status indicates that everything is healthy once again: | |
578 | ||
579 | gwynedd:/u/lnz# cat /proc/rd/status | |
580 | OK | |
581 | ||
582 | ||
583 | EXAMPLE II - DRIVE FAILURE WITH A STANDBY DRIVE | |
584 | ||
585 | The following annotated logs demonstrate the controller configuration and and | |
586 | online status monitoring capabilities of the Linux DAC960 Driver. The test | |
587 | configuration comprises 6 1GB Quantum Atlas I disk drives on two channels of a | |
588 | DAC960PJ controller. The physical drives are configured into a single drive | |
589 | group with a standby drive, and the drive group has been configured into two | |
590 | logical drives, one RAID-5 and one RAID-6. Note that these logs are from an | |
591 | earlier version of the driver and the messages have changed somewhat with newer | |
592 | releases, but the functionality remains similar. First, here is the current | |
593 | status of the RAID configuration: | |
594 | ||
595 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
596 | ***** DAC960 RAID Driver Version 2.0.0 of 23 March 1999 ***** | |
597 | Copyright 1998-1999 by Leonard N. Zubkoff <lnz@dandelion.com> | |
598 | Configuring Mylex DAC960PJ PCI RAID Controller | |
599 | Firmware Version: 4.06-0-08, Channels: 3, Memory Size: 8MB | |
600 | PCI Bus: 0, Device: 19, Function: 1, I/O Address: Unassigned | |
601 | PCI Address: 0xFD4FC000 mapped at 0x8807000, IRQ Channel: 9 | |
602 | Controller Queue Depth: 128, Maximum Blocks per Command: 128 | |
603 | Driver Queue Depth: 127, Maximum Scatter/Gather Segments: 33 | |
604 | Stripe Size: 64KB, Segment Size: 8KB, BIOS Geometry: 255/63 | |
605 | Physical Devices: | |
606 | 0:1 - Disk: Online, 2201600 blocks | |
607 | 0:2 - Disk: Online, 2201600 blocks | |
608 | 0:3 - Disk: Online, 2201600 blocks | |
609 | 1:1 - Disk: Online, 2201600 blocks | |
610 | 1:2 - Disk: Online, 2201600 blocks | |
611 | 1:3 - Disk: Standby, 2201600 blocks | |
612 | Logical Drives: | |
613 | /dev/rd/c0d0: RAID-5, Online, 4399104 blocks, Write Thru | |
614 | /dev/rd/c0d1: RAID-6, Online, 2754560 blocks, Write Thru | |
615 | No Rebuild or Consistency Check in Progress | |
616 | ||
617 | gwynedd:/u/lnz# cat /proc/rd/status | |
618 | OK | |
619 | ||
620 | The above messages indicate that everything is healthy, and /proc/rd/status | |
621 | returns "OK" indicating that there are no problems with any DAC960 controller | |
622 | in the system. For demonstration purposes, while I/O is active Physical Drive | |
623 | 1:2 is now disconnected, simulating a drive failure. The failure is noted by | |
624 | the driver within 10 seconds of the controller's having detected it, and the | |
625 | driver logs the following console status messages: | |
626 | ||
627 | DAC960#0: Physical Drive 1:1 Error Log: Sense Key = 6, ASC = 29, ASCQ = 02 | |
628 | DAC960#0: Physical Drive 1:3 Error Log: Sense Key = 6, ASC = 29, ASCQ = 02 | |
629 | DAC960#0: Physical Drive 1:2 killed because of timeout on SCSI command | |
630 | DAC960#0: Physical Drive 1:2 is now DEAD | |
631 | DAC960#0: Physical Drive 1:2 killed because it was removed | |
632 | DAC960#0: Logical Drive 0 (/dev/rd/c0d0) is now CRITICAL | |
633 | DAC960#0: Logical Drive 1 (/dev/rd/c0d1) is now CRITICAL | |
634 | ||
635 | Since a standby drive is configured, the controller automatically begins | |
636 | rebuilding onto the standby drive: | |
637 | ||
638 | DAC960#0: Physical Drive 1:3 is now WRITE-ONLY | |
639 | DAC960#0: Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 4% completed | |
640 | ||
641 | Concurrently with the above, the driver status available from /proc/rd also | |
642 | reflects the drive failure and automatic rebuild. The status message in | |
643 | /proc/rd/status has changed from "OK" to "ALERT": | |
644 | ||
645 | gwynedd:/u/lnz# cat /proc/rd/status | |
646 | ALERT | |
647 | ||
648 | and /proc/rd/c0/current_status has been updated: | |
649 | ||
650 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
651 | ... | |
652 | Physical Devices: | |
653 | 0:1 - Disk: Online, 2201600 blocks | |
654 | 0:2 - Disk: Online, 2201600 blocks | |
655 | 0:3 - Disk: Online, 2201600 blocks | |
656 | 1:1 - Disk: Online, 2201600 blocks | |
657 | 1:2 - Disk: Dead, 2201600 blocks | |
658 | 1:3 - Disk: Write-Only, 2201600 blocks | |
659 | Logical Drives: | |
660 | /dev/rd/c0d0: RAID-5, Critical, 4399104 blocks, Write Thru | |
661 | /dev/rd/c0d1: RAID-6, Critical, 2754560 blocks, Write Thru | |
662 | Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 4% completed | |
663 | ||
664 | As the rebuild progresses, the current status in /proc/rd/c0/current_status is | |
665 | updated every 10 seconds: | |
666 | ||
667 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
668 | ... | |
669 | Physical Devices: | |
670 | 0:1 - Disk: Online, 2201600 blocks | |
671 | 0:2 - Disk: Online, 2201600 blocks | |
672 | 0:3 - Disk: Online, 2201600 blocks | |
673 | 1:1 - Disk: Online, 2201600 blocks | |
674 | 1:2 - Disk: Dead, 2201600 blocks | |
675 | 1:3 - Disk: Write-Only, 2201600 blocks | |
676 | Logical Drives: | |
677 | /dev/rd/c0d0: RAID-5, Critical, 4399104 blocks, Write Thru | |
678 | /dev/rd/c0d1: RAID-6, Critical, 2754560 blocks, Write Thru | |
679 | Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 40% completed | |
680 | ||
681 | and every minute a progress message is logged on the console by the driver: | |
682 | ||
683 | DAC960#0: Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 40% completed | |
684 | DAC960#0: Rebuild in Progress: Logical Drive 0 (/dev/rd/c0d0) 76% completed | |
685 | DAC960#0: Rebuild in Progress: Logical Drive 1 (/dev/rd/c0d1) 66% completed | |
686 | DAC960#0: Rebuild in Progress: Logical Drive 1 (/dev/rd/c0d1) 84% completed | |
687 | ||
688 | Finally, the rebuild completes successfully. The driver logs the status of the | |
689 | logical and physical drives and the rebuild completion: | |
690 | ||
691 | DAC960#0: Rebuild Completed Successfully | |
692 | DAC960#0: Physical Drive 1:3 is now ONLINE | |
693 | DAC960#0: Logical Drive 0 (/dev/rd/c0d0) is now ONLINE | |
694 | DAC960#0: Logical Drive 1 (/dev/rd/c0d1) is now ONLINE | |
695 | ||
696 | /proc/rd/c0/current_status is updated: | |
697 | ||
698 | ***** DAC960 RAID Driver Version 2.0.0 of 23 March 1999 ***** | |
699 | Copyright 1998-1999 by Leonard N. Zubkoff <lnz@dandelion.com> | |
700 | Configuring Mylex DAC960PJ PCI RAID Controller | |
701 | Firmware Version: 4.06-0-08, Channels: 3, Memory Size: 8MB | |
702 | PCI Bus: 0, Device: 19, Function: 1, I/O Address: Unassigned | |
703 | PCI Address: 0xFD4FC000 mapped at 0x8807000, IRQ Channel: 9 | |
704 | Controller Queue Depth: 128, Maximum Blocks per Command: 128 | |
705 | Driver Queue Depth: 127, Maximum Scatter/Gather Segments: 33 | |
706 | Stripe Size: 64KB, Segment Size: 8KB, BIOS Geometry: 255/63 | |
707 | Physical Devices: | |
708 | 0:1 - Disk: Online, 2201600 blocks | |
709 | 0:2 - Disk: Online, 2201600 blocks | |
710 | 0:3 - Disk: Online, 2201600 blocks | |
711 | 1:1 - Disk: Online, 2201600 blocks | |
712 | 1:2 - Disk: Dead, 2201600 blocks | |
713 | 1:3 - Disk: Online, 2201600 blocks | |
714 | Logical Drives: | |
715 | /dev/rd/c0d0: RAID-5, Online, 4399104 blocks, Write Thru | |
716 | /dev/rd/c0d1: RAID-6, Online, 2754560 blocks, Write Thru | |
717 | Rebuild Completed Successfully | |
718 | ||
719 | and /proc/rd/status indicates that everything is healthy once again: | |
720 | ||
721 | gwynedd:/u/lnz# cat /proc/rd/status | |
722 | OK | |
723 | ||
724 | Note that the absence of a viable standby drive does not create an "ALERT" | |
725 | status. Once dead Physical Drive 1:2 has been replaced, the controller must be | |
726 | told that this has occurred and that the newly replaced drive should become the | |
727 | new standby drive: | |
728 | ||
729 | gwynedd:/u/lnz# echo "make-standby 1:2" > /proc/rd/c0/user_command | |
730 | gwynedd:/u/lnz# cat /proc/rd/c0/user_command | |
731 | Make Standby of Physical Drive 1:2 Succeeded | |
732 | ||
733 | The echo command instructs the controller to make Physical Drive 1:2 into a | |
734 | standby drive, and the status message that results from the operation is then | |
735 | available for reading from /proc/rd/c0/user_command, as well as being logged to | |
736 | the console by the driver. Within 60 seconds of this command the driver logs: | |
737 | ||
738 | DAC960#0: Physical Drive 1:2 Error Log: Sense Key = 6, ASC = 29, ASCQ = 01 | |
739 | DAC960#0: Physical Drive 1:2 is now STANDBY | |
740 | DAC960#0: Make Standby of Physical Drive 1:2 Succeeded | |
741 | ||
742 | and /proc/rd/c0/current_status is updated: | |
743 | ||
744 | gwynedd:/u/lnz# cat /proc/rd/c0/current_status | |
745 | ... | |
746 | Physical Devices: | |
747 | 0:1 - Disk: Online, 2201600 blocks | |
748 | 0:2 - Disk: Online, 2201600 blocks | |
749 | 0:3 - Disk: Online, 2201600 blocks | |
750 | 1:1 - Disk: Online, 2201600 blocks | |
751 | 1:2 - Disk: Standby, 2201600 blocks | |
752 | 1:3 - Disk: Online, 2201600 blocks | |
753 | Logical Drives: | |
754 | /dev/rd/c0d0: RAID-5, Online, 4399104 blocks, Write Thru | |
755 | /dev/rd/c0d1: RAID-6, Online, 2754560 blocks, Write Thru | |
756 | Rebuild Completed Successfully |