This appendix is a complete guide to the /usr/raid5/raidcli command (command-line interface, or CLI). It explains the raidcli parameters, which are summarized in Table B-1.
Bind (group) physical disks
Change parameters for a currently bound group
Destroy the contents of the Challenge RAID storage controller's error log
Reset statistics logging on the Challenge RAID storage-control processor (SP), setting all log counters to 0
Get names and descriptions of devices controlled by the SP
Get information about the storage-system caching environment
Get general system information
Display status information on all system components, such as the fan module, battery backup unit, and so on
Display status information on one disk module or all disk modules in the system
Display the SP log, in which errors are stored, or display the head and tail of the log
Display information about a disk group
Display firmware revision level and controller model number
Change information about the Challenge RAID controller's caching environment
Set statistics logging
Deconfigure physical disks from their current logical configuration, destroying all data on the logical unit (group)
The raidcli command sends Challenge RAID storage management and configuration requests to an application programming interface (API) on the Challenge server. For the raidcli command to function, the agent—an interpreter between the command-line interface and the Challenge RAID storage system—must be running.
|Note: Although the directory is raid5, the command raidcli is valid for all RAID levels.|
The syntax of the raidcli command is
raidcli [-vp] [-d device] parameter [optional_arguments]
In this syntax, options and variables have the following meanings:
Enables verbose return.
Parses the raidcli command without calling the API. If the string does not parse correctly, an error message is printed to stderr; otherwise there is no output.
Target RAID device. Use raidcli getagent for a list of RAID devices. This switch must be present for all raidcli management and configuration commands unless the environment variable indicates otherwise. This switch overrides an environment variable.
The environment variable RaidAgentDevice is the default value for the device when none is specified with the -d flag. If RaidAgentDevice is not set and no -d switch is present, an error is generated on all commands that need device information. For example:
setenv RaidAgentDevice sc4d2l0 setenv RaidAgentDevice /dev/scsi/sc4d2l0
The /dev/scsi prefix is optional.
The physical disk unit number is also known as the logical unit number, or LUN. The unit is a logical concept but is recognized as a physical disk unit by the operating system. The LUN is a hexadecimal number between 0 and 7.
Unlike standard disks, physical disk unit numbers (LUNs) lack a standard geometry. Disk capacity is not a fixed quantity between disk-array LUNs. The effective geometry of a disk-array LUN depends on the type of physical disks in the array and the number of physical disks in the LUN.
|Note: Although bind returns immediate status for a RAID device, the bind does not complete for 15 to 60 minutes, depending on system traffic. Use getlun to monitor the progress of the bind; getlun returns the percent bound. When the bind is complete, each disk is noted as “Enabled” in the getlun output.|
The command raidcli bind is used to group physical disks into RAID-0, RAID-1, RAID-1_0, RAID-3, or RAID-5 units or to create a hot spare:
raidcli -d device bind raid-type lun-number disk-names [optional-args]
Variables in this syntax are explained below.
Target RAID device, as returned by raidcli getagent.
Logical unit number to assign the unit (a hexadecimal number between 0 and 7).
Indicates which physical disks to bind, in the format bd, where b is the physical bus name (a through e; be sure to use lowercase) and d is the device number on the bus (0 through 3). For example, a0 represents the device 0 on bus A, and e2 represents device 2 on bus E.
A RAID-0 bind requires a minimum of 3 and a maximum of 16 disks.
A RAID-1 bind requires 2 disks on separate buses.
A RAID-1_0 bind requires an even number of disks (minimum 2; maximum 16). For high availability, a member of each image pair must be on a different bus. Select the disks in this order: first disk on first bus, first disk on second bus, second disk on first bus, second disk on second bus, third disk on first bus, third disk on second bus, and so on.
A RAID-3 or RAID-5 bind also requires separate buses, each with 5 disks. Legal RAID-3 or RAID-5 bind configurations are
A RAID-5 bind requires a minium of 3 disks and a maximum of 15 disks. For high availability, use groups of 5.
A hot spare bind requires 1 disk, which cannot be A0, B0, C0, D0, E0, or A3. The capacity of the hot spare must be at least as great as the capacity of the largest disk module it might replace.
All disks in a bind should have the same capacity, so that disk space is used fully.
The optional arguments are as follows:
Maximum time in hours to rebuild a replacement disk. Default is 4 hours; legal values are any number greater than or equal to 0.
A rebuild time of 2 hours rebuilds the disk more quickly but degrades response time slightly. A rebuild time of zero hours rebuilds as quickly as possible but degrades performance significantly.
If your site requires fast response time and you want to minimize degradation to normal I/O activity, you can extend the rebuilding process over a longer period of time, such as 24 hours. You can change the rebuild time later without damaging the information stored on the physical disk unit.
Number of blocks per physical disk in a RAID stripe. Default is 128; legal values are any number greater than zero.
The smaller the stripe element size, the more efficient the distribution of data read or written. However, if the stripe size is too small for a single host I/O operation, the operation requires accessing two stripes, thus causing the hardware to read and/or write from two disk modules instead of one. Generally, it is best to use the smallest stripe element size that will rarely force access to another stripe. The default stripe element size is 128 sectors. The size should be an even multiple of 16 sectors (8 KB). For RAID-3, the legal value is 1.
The default is none. Caching is not specified for RAID-3.
Sets the number of stripes in a LUN. For example, if you bind a RAID-5 LUN with a stripe count of 2, you partition the LUN into two stripes, thus preventing access to the remaining available space. This option is useful for short bind operations. Legal values are any number greater than or equal to 0. The default value is 0, which binds the maximum number of stripes available.
The following example binds disks A1, B1, C1, D1, and E1 into a RAID-5 logical unit with a logical unit number of 3, a four-hour maximum rebuild time, and a 128-block stripe size per physical disk, with read cache enabled:
raidcli -d sc4d2l0 bind r5 3 a1 b1 c1 d1 e1 -r 4 -s 128 -c read
The following example binds disks A1, B1, C1, D1, and E1 into a RAID-3 LUN with a LUN number of 3, a four-hour maximum rebuild time, and a RAID-3 memory size of 6 MB. (this example presumes that memory has already been allocated with raidcli setcache.
raidcli -d sc4d2l0 bind r3 3 a1 b1 c1 d1 e1 -r 4 -r3 6
The following example binds A2 and B2 into a RAID-1 logical unit with a LUN number of 2 and a four-hour maximum rebuild time, with read cache enabled:
raidcli -d sc4d2l0 bind r1 2 a2 b2 -r 4 -c read
The following example binds disks A1, B1, C1, and D1 into a RAID-1_0 logical unit with a LUN number of 1, a four-hour maximum rebuild time, and a 128-block stripe size per physical disk, with read cache enabled:
raidcli -d sc4d2l0 bind r1_0 1 a1 b1 c1 d1 -r 4 -s 128 -c read
The following example binds A2, B2, C2, D2, and E2 into a RAID-0 logical unit with a LUN number of 3, and a 128-block stripe size per physical disk, with read cache enabled:
raidcli -d sc4d2l0 bind r0 3 a2 b2 c2 d2 e2 -s 128 -c read
The following example binds disk E3 as a hot spare with a LUN number of 7:
raidcli -d sc4d2l0 bind hs 7 e3
There is no output for raidcli with the bind parameter. Errors are printed to stderr.
|Note: For complete messages, it is recommended that you use the -v option.|
The command raidcli chglun is used to change parameters for a LUN:
raidcli -d device chglun [-l lun] [-c cache-flags] [-d default-owner] [-r rebuild-time] [-i idle-thresh] [-t idle-delay-time] [-w write-aside] [-a autotrespass] [-pf prefetch type] [-rt retention type] [-sc configure-read-cache] [-sm segment-size/multiplier] [-pm prefetch-size/multiplier] [-mp max-prefetch] [-pd prefetch-disable] [-pc prefetch-idle-count]
|Note: Only root can use this parameter.|
In this syntax, variables mean the following:
Logical unit number to be changed
The default is none.
If your storage system has dual SPs, see “Dual Interfaces, Load Balancing, and Device Names” in Chapter 4.
Maximum time in hours to rebuild a replacement disk. Default is four hours; legal values are any number greater than or equal to 0.
Maximum number of I/Os that can be outstanding to a LUN and have the LUN still be considered idle. Used to determine cache flush start time. Legal values are 0 to 255; the default is 0. A value of 255 leaves the previous setting unchanged.
The smallest write request size, in blocks, that bypasses the cache and goes directly to the disks. Legal values are 16 to 65535; the default is 2048. A value of 65535 leaves the previous setting unchanged.
Enables or disables automatic failover and read/write access by both SPs to a LUN. Values are
Retention determines whether or not prefetched data has equal or favored priority over host-requested data when the read cache becomes full. Values are
Legal values for segment size are 0 to 255; a value of 255 leaves the previous setting unchanged. Legal values for the segment multiplier are 1 to 32; the default is 4.
You can specify a segment size that is equal to or less (but not greater) than the prefetch size. You can specify a segment multiplier that is equal to or less (but not greater) than the prefetch multiplier. If you specify a segment multiplier that is equal to the prefetch multiplier, prefetch operations are not divided into segments.
|-pc prefetch idle count|
The following example changes LUN 3 to perform write caching and rebuild in four hours; it does not change the default owner:
raidcli -d sc4d2l0 chglun -l 3 -c write -d 0 -r 4
There is no output for raidcli with the chglun parameter. Errors are printed to stderr.
The clearlog parameter destroys the contents of the Challenge RAID SP's error log. Its syntax is
raidcli -d device clearlog
|Note: You must be root to use this parameter.|
This command has no output.
The clearstats parameter resets statistics logging on the Challenge RAID SP, resetting all log counters to 0. The command raidcli clearstats is used to reset statistics logging:
raidcli -d device clearstats
|Note: You must be root to use this parameter.|
This command has no output.
The command raidcli getagent is used to display information on devices controlled by the API:
The following is sample output for one device; normally, the output would give information on all devices:
Agent Rev: 1.55.0 Name: Disk Array Desc: RAID5 Disk Array Node: sc4d2l0 Signature:0xf3b51700 Peer Signature: 0x657e0a00 Revision: 9.3.0, Model: 7305 SCSI Id: 1 Prom Rev: 1.55.0 SP Memory: 64 Serial No: 96-7240-808
Table B-2 summarizes entries in the raidcli getagent output.
Table B-2. Output of raidcli getagent
Revision number of RAID agent
ASCII string found in the agent configuration, which that assigns a name to the node being accessed (see node description below)
ASCII string found in the agent configuration file, which describes the node being accessed (see node description below)
The /dev/scsi entry that the agent uses as a path to the actual SCSI device; this value must be entered by the user for every CLI command (except getagent)
Unique 32-bit identifier for the SP being accessed through Node
Unique 32-bit identifier for the other SP in the chassis; 0 if no additional SP is present
Revision of firmware currently running on the SP and model of the SP:
7305: PowerPC-based SP
SCSI ID number
Current PROM revision on the SP
Amount of DDRAM present on the SP
12-digit ASCII string that uniquely identifies this subsystem
If you use storage system caching, you can use the raidcli getcache command to get information on cache activity. The information in this command's output, particularly the percentage of cache hits, may help you decide on the most efficient cache page size and whether a physical disk unit really benefits from caching.
The command raidcli getcache is used to display cache information:
raidcli -d device getcache
The following is sample output:
Usable Cache: 8 Page size: 2KB Write Cache State: Enabled Low Watermark; 75 High Watermark: 90 SP A Cache Pages: 2048 SP B Cache Pages: 2047 Unassigned Cache Pages: 0 Read Hit Ratio: 82 Write Hit Ratio: 74 Prct Dirty Cache Pages = 63 Prct Cache Pages Owned = 50 Prct Read Flushes = 10 Prct Write Flushes = 12 SPA Read Cache State enabled SPB Read Cache State enabled Minimum system memory allowed 2 MB Physical memory size of spA = 8 MB Physical memory size of spB =16 MB System memory size of spA = 8 MB System memory size of spB = 8 MB Read Cache Size of spA = 3 MB Read Cache Size of spB = 3 MB Raid 3 memory size for spA = 2 MB Raid 3 memory size for spB = 2 MB Free Memory size of spA = 5 MB Free Memory size of spB = 5 MB
Table B-3 summarizes entries in the raidcli getcache output.
Table B-3. Output of raidcli getcache
Size of cache in megabytes to use for caching, not greater than the SP memory size as displayed by raidcli getagent (see “getagent,” earlier in this appendix). Valid values are 0, 8, and 64. Defaults are 0 (user has selected to disable the cache) and 8 (user has selected to enable the cache).
The command-line interface does not let you specify more memory than you have. If you specify less than you have, the remaining memory is unused.
User-specified page size in KB for caching; for example, 2 means a 2 KB page size.
Write Cache State
Enabled: SP is fully functional.
Disabled: SP not capable of or configured for caching.
Synching: SP is synchronizing its cache with the peer SP.
Enabling: cache is in the process of becoming enabled.
Quiescing: cache was enabled but system experienced a fault or was disabled by user. The system is now finishing processing outstanding I/O before saving the contents of the cache.
Frozen: SP has finished quiescing and is now waiting for peer SP to finish quiescing or dumping.
Dumping: SP is in the process of dumping contents of the cache to a private location on the disk.
Initing: SP is initializing.
Percentage of dirty cache pages that, when reached during flush operations, causes the SP to cease flushing the cache.
Valid values are 0 through 100; the default is 50, regardless of whether caching is enabled or disabled.
Percentage of dirty cache pages which, when reached during flush operations, causes the SP to cease flushing the cache.
Valid values are 0 through 100; the setting must be greater than the low watermark. The default is 75, regardless of whether caching is enabled or disabled.
SP A Cache Pages
SP B Cache Pages
Total number of cache pages currently owned by SP A; each page has the cache page size selected when storage-system caching was set up. This number equals the cache size divided by the cache page size, minus space for checksum tables. If the storage system has two working SPs, they divide the total number of pages between them. If an SP is idle for a long period or fails, the active SP may increase its share of pages.
Unassigned Cache Pages
Number of dirty cache pages not owned by A or B. These can occur when a unit is broken and there are no disks to which to flush the dirty pages.
Read Hit Ratio
Percent of read requests to the SP that can be satisfied from the cache without requiring disk access.
Write Hit Ratio
Percent of write requests to the controller that can be satisfied with the cache without requiring disk access. A write cache hit occurs when the SP finds and modifies data in the write cache memory, which usually saves a write operation.
For example, a hit that occurs when a page is sought in a RAID 5 LUN eliminates the need to read, modify, and write the data. High ratios are desirable because each hit indicates at least one disk access that was not needed.
Prct Dirty Cache Pages
Percentage of pages that have been modified in the SP's write cache, but that have not yet been written to disk. A high percentage of dirty pages means the cache is handling many write requests.
Prct Cache Pages Owned
Percentage of cache pages owned by this controller when pages from other SP are taken into account.
Prct Read Flushes
Percentage of reads to SP that caused the cache to flush a page(s).
Prct Write Flushes
Percentage of writes to SP that caused the cache to flush a page(s).
SP Read Cache State
Enabled or Disabled.
Minimum system memory allowed
AMD-based SP: 2 MB; PowerPC-based SP: 4 MB.
Physical memory size of SP
Number of MB in SP's physical memory.
System memory size of SP
Number of MB in SP's system memory.
Read Cache Size of SP
Number of MB in SP's read cache.
Raid 3 memory size for SP
Number of MB allocated to RAID-3 memory.
Free Memory size of SP
The command raidcli getcontrol is used to get general system information:
raidcli -d device getcontrol
A sample output of this command follows:
System Fault LED: OFF Statistics Logging: ON System Cache: ON Max Requests: 23 Average Requests: 5 Hard errors: 0 Total Reads: 18345 Total Writes: 1304 Prct Busy: 25 Prct Idle: 75 System Date: 7/5/1996 Day of the week: Friday System Time: 12:43:54 read_requests: 145 write_requests: 34642049 blocks_read: 1633 blocks_written: 363696414 sum_queue_lengths_seen_by_arrivals: 401 arrivals_to_non_zero_queue: 400 hw_flush_on: 0 idle_flush_on: 5314 lw_flush_off: 0 write_Cache_flushes: 98 write_cache_blocks_flushed: 1150 Internal bus 1 busy ticks: 429 Internal bus 1 busy ticks: 429 Internal bus 2 busy ticks: 429 Internal bus 2 busy ticks: 429 Internal bus 3 busy ticks: 429 Internal bus 3 busy ticks: 429 Internal bus 4 busy ticks: 429 Internal bus 4 busy ticks: 429 Internal bus 5 busy ticks: 429 Internal bus 5 busy ticks: 429 Controller busy ticks: 1403792 Controler idle ticks: 3775334
In the getcontrol output,
statistics logging is always turned on by the agent
hard errors are those returned to the host
total reads and writes are the totals as seen by the SP
system time is in 24-hour format
The command raidcli getcrus displays state information on every field-replaceable unit in the Challenge RAID storage system except disks in the disk modules:
raidcli -d device getcrus
Sample output of this command follows.
FANA State: Present FANB State: Present VSCA State: Present VSCB State: Present VSCC State: Present SPA State: Present SPB State: Present BBU State: Present
Table B-4 interprets items in this output. Values for all entries of the output are Present or Not Present, except as noted.
Table B-4. Output of raidcli getcrus
Fan banks A and B.
Power supply (voltage semi-regulated converter).
Optional third power supply.
Storage control processor.
Optional second storage-control processor.
Battery backup unit, which has three states: Present (fully charged) and Not Present (removed or charging).
If the battery backup unit takes longer than an hour to charge, it shuts itself off and transitions to the “Faulted” state.
The command raidcli getdisk displays information on all disks in the system, whether bound or not:
raidcli -d device getdisk
For information on a particular disk, use
raidcli -d device getdisk [diskposition]
In this command, diskposition has the format bd, where b is the bus on which the disk is located (a through e) and d is the device number (0 through 3). Figure B-1 diagrams disk module locations.
For example, the following command retrieves information for disk A0:
raidcli -d sc4d2l0 getdisk a0
A sample output of this command follows.
A0 Vendor Id: <manufacturer> Ao Product Id: <part number> A0 Lun: 0 A0 State: Bound and Not Assigned A0 Hot Spare: NO A0 Prct Rebuilt: 100 A0 Prct Bound: 100 A0 Serial Number: 00019699 A0 Capacity: 0x000f42a8 A0 Private: 0x00009000 A0 Bind Signature: 0x1c4eb2bc A0 Hard Read Errors: 0 A0 Hard Write Errors: 0 A0 Soft Read Errors: 0 A0 Soft Write Errors: 0 A0 Read Retries: 0 A0 Write Retries: 0 A0 Remapped Sectors: 0 A0 Number of Reads: 1007602 A0 Number of Writes: 1152057
Table B-5 interprets items in this output.
Table B-5. Output of raidcli getdisk
Manufacturer of disk drive
Part number of disk
Logical unit number to which this disk is bound
Removed: disk is physically not present in the chassis or has been powered off
Off: disk is physically present in the chassis but is not spinning
Powering Up: disk is spinning and diagnostics are being run on it
Unbound: disk is healthy but is not part of a LUN
Bound and Not Assigned: disk is healthy, part of a LUN, but not being used by this SP
Rebuilding: disk is being rebuilt
Enabled: disk is healthy, bound, and being used by this SP
Binding: disk is in the process of being bound to a LUN
Formatting: disk is being formatted
YES or NO
Percentage of disk that has been rebuilt
Percentage of disk that has been bound
Serial number from disk inquiry command
Actual disk capacity in blocks
Amount of physical disk reserved for private space
Unique value assigned to each disk in a logical unit at bind time
Hard Read Errors
Number of hard errors encountered on reads for this disk
Hard Write Errors
Number of hard errors encountered on writes for this disk
Soft Read Errors
Number of soft errors encountered on reads for this disk
Soft Write Errors
Number of soft errors encountered on writes for this disk
Number of retries occurring during reads
Number of retries occurring during writes
Number of sectors that have been remapped
Number of Reads
Number of reads this disk has seen
Number of Writes
Number of writes this disk has seen
The SP maintains a log of event messages in its memory. These events include hard errors, startups, and shutdowns involving disk modules, fans, SPs, power supplies, and the battery backup unit. Periodically, the SP writes this log to disk to maintain it when SP power is off. The log can hold over 2,000 event messages; it has a filter feature that lets you select events by device or error message.
The event messages are in chronological order, with the most recent messages at the end. The command raidcli getlog is used to display the entire log:
raidcli -d device getlog [+N | -N] [-v]
The +N argument displays the newest n entries in the log, starting with the oldest entry:
raidcli -d device getlog +N
The -N argument displays the oldest N entries in the log, starting with the oldest entry:
raidcli -d device getlog -N
The following is a possible output of the command raidcli getlog +5:
12/17/96 09:59;51 A3: (A07) Cru Removed [0x47] 12/17/96 09:59;51 A3: (608) Cru Ready [0x0] 12/17/96 09:59;51 A3: (603) Cru Rebuild Started [0x0] 12/17/96 09:59;51 A3: (604) Cru Rebuild Complete [0x0] 12/17/96 09:59;51 A3: (602) Cru Enabled [0x0]
These entries show that a field-replaceable unit (disk module, fan unit, battery backup unit, SP) has been removed, replaced, rebuilt, and enabled.
At the tail of each log entry is an error code in brackets that gives diagnostic information when it is available. Table B-6 summarizes the error codes.
Invalid command-line parameters
Too few parameters
Too many parameters
Invalid bind type
Invalid LUN number
Invalid rebuild time
Invalid number of disks in bind command
Valid disk names are of format a0, b1, ... e3, etc.
Invalid stripe size
Invalid disk name
Invalid cache flags
Invalid default owner
Incorrect number of chglun parameters
Unable to determine name of target host system
Enable-disable flag invalid
Invalid usable cache size
Invalid page size
Invalid watermark value
High watermark less than low watermark
No device name listed
Invalid idle threshold
Invalid idle delay
Invalid write aside size
Disks must be on separate buses for bind
The agent was unable to configure any devices
LUN does not exist
LUN already exists
Cannot get current working directory for firmware command
Agent encountered an error during SCSI execution
Agent encountered an error during serial port execution
Agent returned an operating system error
Agent returned an internal agent error code
Cannot communicate with agent
RPC error encountered
More detailed descriptions of the above errors can be seen when verbose mode is enabled ( -v).
The command raidcli getlun is used to display information on a logical unit and the components in it. The syntax is
raidcli -d device getlun lun-number
The following example displays information about LUN 0:
raidcli -d sc4d2l0 getlun 0
|Note: If numbers in the output look unreasonable, particularly for numerical statistics such as Queue Max, use clearstats to reset all statistics.|
Below is truncated output for a RAID-5 group of five disks.
|Note: Information on individual disks is not displayed unless statistics logging is enabled with raidcli setstats. See “getcontrol” earlier in this appendix.|
Prefetch size multiplier = 4 Segment size/multiplier = 4 Maximum prefetch = 512 Prefetch Disable = 129 Prefetch idle content = 40 Variable length prefetching Prefetch data retained Read cache configured according to specified parameters Read Histogram 194560 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Write Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read Histogram 1945 60 Read histogram overflows 0 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write Histogram 194560 Write histogram overflows 0 Read requests 10 Write Requests 24225638 Blocks read 61 Blocks written Read cache hits 4 Read cache misses 6 Prefetched blocks 51 Unused prefetched blocks 0 Write cache hits 24225043 Forced flushes 0 Type: RAID5 Stripe size: 128 Capacity: 0x10000 Current owner: YES Auto-trespass: Disabled Auto-assign; Enabled Write cache: Disabled Read cache: Disabled Idle Threshold: 0 Idle Delay Time: 20 Write Aside Size: 2048 Default Owner: YES Rebuild Time: 0 Read Hit Ratio: 0 Write Hit Ratio: 0 Prct Reads Forced Flushed: 0 Prct Writes Forced Flushed: 0 Prct Rebuilt: 100 Prct Bound: 100 A0 Enabled A0 Reads: 62667 A0 Writes: 29248 A0 Blocks Read: 3212517 A0 Blocks Written: 471642 A0 Queue Max: 26 A0 Queue Avg: 1 A0 Avg Service Time: 14 A0 Prct Idle: 100 A0 Prct Busy: 0 A0 Remapped Sectors: 0 A0 Read Retries: 50 A0 Write Retries: 0 B0 Enabled B0 Reads: 66946 [etc.] C0 Enabled C0 Reads: 69342 [etc.] D0 Enabled D0 Reads: 68558 [etc.] E0 Enabled Eo Reads: 69721 [etc.]
Table B-7 summarizes entries in the raidcli getlun output.
Table B-7. Output of raidcli getlun
For prefetching (read-ahead caching), prefetch size and multiplier determine the amount of data prefetched for one host read request. For constant-length prefetching, the prefetch size is the number of blocks to prefetch. The range for the prefetch size is 1-2048 blocks. The range for the prefetch multiplier is 1-32; the default is 4. For more details, see “Changing LUN Parameters” in Chapter 8.
Segment size and multiplier determine the size of the segments that make up a prefetch operation. An SP reads one segment at a time from the LUN because smaller prefetch requests interfere less with other host requests. The range for the segment size is 0-254 blocks. The range for the prefetch multiplier is 1-32; the default is 4.
Maximum number of blocks to prefetch for variable-length prefetching. The range is 1-2048; the default is 512 sectors.
Number read request sectors that disables prefetch; this number is so large that prefetching data would not be beneficial; for example, if the amount of requested data is equal to or greater than the size of the read cache. The range is 1-65279; the default is 129.
Prefetch idle content
Leave this parameter set to 40 (the default).
Variable/Constant length prefetching
Prefetch type: determines whether to prefetch data of a variable or constant length or to disable prefetching. The default is variable-length prefetching.
Prefetch data retained
Retention determines whether or not prefetched data has equal or favored priority over host-requested data when the read cache becomes full. The default is Favor prefetch, which is suitable for most applications.
RAID0: nonredundant individual access array
Sectors per disk per stripe with which the unit was bound
Number of sectors total for use by user
YES if this SP owns the unit; NO if it does not
Set with chglun; see “Dual Interfaces, Load Balancing, and Device Names” in Chapter 4
Enabled or Disabled; Disabled is recommended
Enabled or Disabled; Disabled is recommended
Enabled means this LUN is write caching; otherwise, Disabled
Enabled means this LUN is read caching; otherwise, Disabled
Maximum number of I/Os outstanding; determines cache flush start time; set with chglun
Idle Delay Time
Amount of time in 100-ms intervals that unit is below idle threshold; set with chglun
Write Aside Size
Smallest write-request size in blocks that can bypass the cache and go directly to the disk; set with chglun
YES if this SP is the default owner (not necessarily current owner) of this LUN, otherwise, NO
Amount of time in hours in which a rebuild should be performed. 0 means rebuild as fast as possible, but means a degradation in host I/O performance
Read Hit Ratio
Percentage of read requests to the controller that can be satisfied from the cache without requiring disk access
Write Hit Ratio
Percentage of write requests to the cache that can be satisfied with the cache without requiring a disk access
Prct Reads Forced Flushed
Percentage of read requests that flushed the cache
Prct Writes Forced Flushed
Percentage of write requests that flushed the cache
Percentage complete during a rebuild
Percentage complete during a bind
Enabled, Binding, etc. (same as for getdisk)
Total number of reads this disk has done
Total number of writes this disk has done
Diskname Blocks Read
Total number of blocks this disk has read
Diskname Blocks Written
Total number of blocks this disk has written
Diskname: Queue Max
Maximum number of I/Os queued up to this drive
Diskname: Queue Avg
Average number of I/Os queued up to this drive
Diskname: Avg Service Time
Average service time in milliseconds
Diskname: Prct Idle
Percentage of time disk is not servicing request
Diskname: Prct Busy
Percentage of time disk is servicing request
Diskname: Remapped Sectors
Number of remaps that have occurred on this disk
Diskname Read Retries
Number of read retries that have occurred on this disk
Diskname Write Retries
Number of write retries that have occurred on this disk
The getsp parameter returns the firmware (FLARE) revision number and the SP model number for the specified device:
raidcli -d device getsp
In the output, Model 7624 is the AMD-based SP and Model 7305 is the PowerPC-based SP. Example output:
Revision 8.20.0, Model: 7624
For systems containing many Challenge RAID chassis assemblies, this parameter is especially useful as an alternative to raidcli getagent when the firmware revision number and model number of a specific SP is desired.
This parameter is available for RAID agent 1.55 and later.
The cache parameters you specify for the entire storage system are the cache size of 8 or 64 MB, depending on the amount of memory the SP has, and the cache page size, as 2, 4, 8, or 16 KB.
The command raidcli setcache is used to set up caching:
raidcli -d device setcache enable | disable [-u usable] [-p page] [-l low] [-h high] [-sma system-memory-SPA] [-smb system-memory-SPB] [-sta read-cache-state-SPA] [-stb read-cache-state-SPB] [-rca read-cache-size-SPA] [-rcb read-cache-size-SPB] [-r3 raid3-memory-size]
In this syntax, variables have the following meanings:
|enable | disable|
Enter 1 to enable write caching or 0 to disable write caching.
Using setcache 1 with options takes 45 seconds while cache states are disabled; cache dumping might take some time.
Size in megabytes to use for caching, not greater than the SP memory size as displayed by raidcli getagent (see “getagent,” earlier in this appendix). Valid values are 0 through 64 in increments of 1 MB.
The command-line interface does not let you specify more memory than you have. If you specify less than you have, the remaining memory is unused.
Size in KB of pages into which to partition the cache. Valid sizes are 2, 4, 8, and 16. The default is 2, regardless of whether caching is enabled or disabled.
Generally, set cache page size to 8 KB for IRIX file server applications and 2 KB or 4 KB for database applications.
Percentage of cache full that discontinues flushing. Valid values are 0 through 100; the default is 50, regardless of whether caching is enabled or disabled.
Percentage of cache full that initiates flushing. Valid values are 0 through 100; the setting must be greater than the low watermark. The default is 75, regardless of whether caching is enabled or disabled.
|-sma system-memory-SPA, -smb system-memory-SPB|
|-sta read-cache-state-SPA, stb read-cache-state-SPB|
|-rca read-cache-size-SPA, -rcb read-cache-size-SPB|
|Note: The sum of an SP's write cache size, system memory size, and read cache size must be less than or equal to the SP's physical memory size.|
This command has no output.
You can change the cache size, the cache page size values, or the type of caching for any physical disk unit without affecting the information stored on it. Follow these steps:
Disable the cache:
raidcli -d device setcache 0
Wait for the cache memory to be written to disk, which may take several minutes.
Reassign cache size and re-enable caching:
raidcli -d device setcache 1 -u 64 [parameters]
|Note: Before changing a cache parameter, you must always disable the cache.|
The following command sets cache memory for fast RAID-3 at 16 MB, which is sufficient for two SPs at 8 MB each in a failover system:
setcache -d sc4d2l0 1 -r3 16
The following example enables the system cache with an 8 MB cache partitioned into 8 KB pages, with a 50% low watermark value and a 75% high watermark value:
setcache -d sc4d2l0 1 -u 8 -p 8 -l 50 -h 75
The setstats parameter sets statistics logging:
raidcli setstats [-on | -off]
If no optional switch is present, this command returns the current state of statistics logging.
You must be root to use this parameter.
The command raidcli setstats -on enables statistics logging; raidcli setstats -off disables it. With the optional switch, this command has no output.
If statistics logging is off, certain options in other commands are disabled. The option descriptions for these other commands specify whether statistics logging must be on for their options to be valid.
The unbind parameter unconfigures physical disks from their current logical configuration into LUNs.
|Caution: This parameter destroys all data on the LUN (disk group).|
You must be root to use this parameter. The command prompts you for verification before issuing the unbind, unless you override it with the -o flag.
The command raidcli unbind is used to unbind disks:
raidcli -d device unbind lun-number [-o]
In this syntax, variables and options mean:
Number of the logical unit (LUN) to deconfigure.
When raidcli unbind is entered, a prompt appears asking the user for verification before the unbind is issued. This flag disables this prompt.
This command has no output.
The following example destroys LUN 3 and frees its disks to be reconfigured, with no prompting to the user:
unbind -d sc4d2l0 3 -o