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linux:raid [2013/07/15 20:44] admin |
linux:raid [2017/03/20 11:51] (current) tomsa [Setting up RAID10 with tw_cli] |
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mdadm: ... critical section passed. | mdadm: ... critical section passed. | ||
# | # | ||
+ | </code> | ||
+ | |||
+ | **Nekdy se muze hodit:** | ||
+ | |||
+ | tags: 3ware tw_cli replace drive | ||
+ | |||
+ | <code> | ||
+ | echo "0 0 0" > /sys/bus/scsi/devices/0\:0\:4\:0/rescan | ||
</code> | </code> | ||
===== Links ===== | ===== Links ===== | ||
Line 115: | Line 123: | ||
7 8 145 7 active sync /dev/sdj1 | 7 8 145 7 active sync /dev/sdj1 | ||
</code> | </code> | ||
+ | |||
+ | ====== Speed Up ====== | ||
+ | <code> | ||
+ | echo 6144 > /sys/block/md3/md/stripe_cache_size | ||
+ | echo 40000 > /proc/sys/dev/raid/speed_limit_min | ||
+ | echo 256000 > /proc/sys/dev/raid/speed_limit_max | ||
+ | </code> | ||
+ | |||
====== 3ware Utility ====== | ====== 3ware Utility ====== | ||
* http://www.3ware.com/support/download.asp (the 900kB one!) | * http://www.3ware.com/support/download.asp (the 900kB one!) | ||
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ctrl slot=0 create type=ld drives=1I:1:3 raid=0 | ctrl slot=0 create type=ld drives=1I:1:3 raid=0 | ||
</code> | </code> | ||
+ | |||
+ | ====== RAID10 performance ====== | ||
+ | mdadm -v --create /dev/md0 --level=raid10 --layout=f2 --raid-devices=4 ... | ||
+ | The trick is "layout=f2" as the man page says> | ||
+ | '' Finally, the layout options for RAID10 are one of 'n', 'o' or 'f' followed by a small number. The default is 'n2'. The supported options are: | ||
+ | |||
+ | 'n' signals 'near' copies. Multiple copies of one data block are at similar offsets in different devices. | ||
+ | |||
+ | 'o' signals 'offset' copies. Rather than the chunks being duplicated within a stripe, whole stripes are duplicated but are rotated by one device so | ||
+ | duplicate blocks are on different devices. Thus subsequent copies of a block are in the next drive, and are one chunk further down. | ||
+ | |||
+ | 'f' signals 'far' copies (multiple copies have very different offsets). See md(4) for more detail about 'near', 'offset', and 'far'. | ||
+ | |||
+ | The number is the number of copies of each datablock. 2 is normal, 3 can be useful. This number can be at most equal to the number of devices in the | ||
+ | array. It does not need to divide evenly into that number (e.g. it is perfectly legal to have an 'n2' layout for an array with an odd number of | ||
+ | devices). | ||
+ | |||
+ | '' | ||
+ | ====== Setting up RAID10 with tw_cli ====== | ||
+ | Generating the RAID10 field with disks in ports from 8 to 17: | ||
+ | ./tw_cli /c0 add type=raid10 disk=8-17 noautoverify | ||
+ | Software way of removing a disk from port 14: | ||
+ | ./tw_cli maint remove c0 p14 | ||
+ | Taking a look of what has it done: | ||
+ | ./tw_cli /c0/u0 show | ||
+ | "Adding" a disk back to the file system (more like identifying it): | ||
+ | ./tw_cli maint rescan c0 | ||
+ | Starting the verification process (if the unit was not previously initialized, it will be): | ||
+ | ./tw_cli /c0/u0 start verify | ||
+ | If you need to check which disk is connected to each port, you can use this command, it will light the external GUI light: | ||
+ | ./tw_cli /c0/p16 set identify=on | ||
+ | |||
+ | Add disk to raid: | ||
+ | tw-cli /c0/u0 start rebuild disk=16 | ||
+ | |||
+ | If the disk is in another unit (i.e. u1), just delete the unit | ||
+ | tw-cli /c0/u1 del | ||
+ | |||
+ | Problem: after physically removing a disk and installing it back, RAID started re-initializing by its own will without letting the master know. It's just bad. | ||
+ | |||
+ |
linux/raid.1373913851.txt.gz · Last modified: 2013/07/15 20:44 by admin