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On Wed, Jul 3, 2013 at 2:29 AM, Stefan G. Weichinger <lists@×××××.at> wrote: |
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> Am 03.07.2013 00:42, schrieb Paul Hartman: |
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>> On Tue, Jul 2, 2013 at 2:56 PM, Stefan G. Weichinger <lists@×××××.at> wrote: |
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>>> |
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>>> Does anyone use that controller with gentoo? |
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>>> |
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>>> If yes, which driver/module does support it? |
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>>> |
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>>> I ordered one for a server and did not really check the facts ;-) |
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>> |
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>> Looks like it uses the LSI SAS2008 chipset (basically LSI controller |
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>> with HP branding), so you should enable kernel module mpt2sas |
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>> (CONFIG_SCSI_MPT2SAS) and probably some other SAS-related options will |
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>> be required as well if you don't already use them. |
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>> |
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>> I actually just installed a card with this same chipset in my Gentoo |
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>> machine yesterday! I have not attached disks to it yet, as I am |
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>> waiting for the enclosure to be delivered, but so far nothing froze or |
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>> burst into flames when the module loaded. :) I even upgraded the BIOS |
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>> and firmware on the card from within linux and everything seems okay, |
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>> so far. |
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> |
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> Thanks a lot, Paul, for that feedback. Seems that you will be the first |
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> to really test it, my box will arrive next week, I assume. This will be |
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> an installation from scratch so no SAS-related stuff there already. |
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> |
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> I wonder if it makes sense to attach the disks to that adapter as well? |
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> This box will do amanda backups ... so there will be the amanda holding |
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> disk and it is important to have maximum speed between that holding area |
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> and the tape drive. I plan RAID1 on 2x2TB disks at least or maybe even |
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> RAID0 (it's a rather temporary storage area so the redundancy isn't that |
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> important). Testing will show! |
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Mine will be attached to an external 8-disk storage array with 2 |
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external SAS cables (4 disks per cable). I had a 5-disk 8TB software |
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RAID5 in my computer that I had to remove due to an unplanned |
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motherboard upgrade. Right now the disks are in a cheap external |
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5-disk eSATA/USB JBOD enclosure plugged into the eSATA port on my |
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motherboard, but it's not able to access all disks at the same time, |
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so the RAID5 performance is awful. Around 10-20 MB/sec on writes and |
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max 50MB/sec on reads. (It was previously 100MB+/sec for both |
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operations.) |
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In the eSATA enclosure, a single scrub (check) of my array takes FOUR |
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DAYS to complete! I worry about what will happen if I have to replace |
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a disk, the rebuild would take forever... what if there is a power |
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outage and my UPS battery only lasts around 30 minutes? |
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I bought two of the lowest-quality 4tb Seagate drives for US$140 each |
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on sale and plan to use them to make a backup copy of my files from |
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the RAID onto those drives. So far I have never made a backup of my |
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RAID because I never had enough storage space to duplicate it all. |
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"RAID is not a backup" has been repeating in my head for all these |
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years. Horror stories about a corrupt filesystem, or 1 bad sector |
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causing the whole RAID5 rebuild to fail. Now that I will have extra |
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drive bays, maybe I can add a second parity drive and try to do an |
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online upgrade from RAID5 to RAID6. I definitely want to make a good |
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backup before I try that... |
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I am hopeful that the SAS controller and enclosure should give me high |
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performance again! I will let you know how it goes. |
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BTW, I am using the latest 3.9 series linux kernel. |
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