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8

It's a hard disk with a FC interface. Nope, you probably can't just arbitrarily replace one of them with a disk with a different interface, and different IO characteristics, especially in a storage array. But ask your vendor to be certain, or consult their documentation! And, spend 30 seconds on Google, too.


7

HBA just means 'host bus adapter', so it's anything that lets you connect to an external bus (although usually the term is applied to a something that lets you connect storage). You might put one in to fit an external tape drive, or a SAN storage array. Usually, as in this case, it means the card isn't that intelligent. It supports only the simple types of ...


4

HBA: Device that plugs into your computer's bus and allows it to talk to hard drives. It may or may not provide RAID, acceleration, or other such features. RAID controller: Device that provides RAID support, usually with hardware acceleration. It may or may not connect to your computer's bus. It may, for example, connect to a SATA port.


4

The contents of /proc/diskstats, and the output of 'iostat' on it's own, both show the cumulative stats since the counters were reset (probably since the machine booted). If your webserver is serving primarily HTML and simple SQL, it's very likely it's mostly coming out of memory caches, and so very little is hitting the disk for a read. On the other hand, ...


3

It may not matter, depending on what your goals are... there are gray areas between both definitions - RAID controller and Host-Bus Adapter (HBA). Understand that most high-quality servers have embedded RAID controllers today, so the need to select and shop for a separate RAID card has diminished as systems become more integrated... RAID controller cards ...


2

If performing a low-level format on a 4TB drive takes 16 hours, it's formatting at a rate 70MB/s. That's comparable to the 100MB/s at which you say you can normally write to the drive.


2

The 0834 line are Fibre Channel disk shelves (ie, they just hold a bunch of disks and aggregate their host interfaces). They take fibre channel disks, not SATA or SAS, and provide a FC interface to one or more host systems (initiators in storage parlance). Since they're just passing access through they'll support any disk that supports the same physical ...


2

You're expecting a JBOD, but it appears that this might be set up as a SAN, and you're seeing LUNs. You should check the 6140s themselves.


2

I'd probably just compare fdisk -l and lsscsi. On my systems, I tend to see more output in fdisk, as lsscsi doesn't account for all of the block devices in use on the servers (ZFS zpool devices, etc.) Similar situation for blkid.


2

For the amount of data, see iostat: [root@example ~]# iostat -m Linux 2.6.32-431.11.2.el6.x86_64 (example.com) 08/08/2014 _x86_64_ (2 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 0.38 0.00 4.10 0.36 0.10 95.07 Device: tps MB_read/s MB_wrtn/s MB_read MB_wrtn sda 0.95 ...


1

This depends on your server, the backplane and whether an expander is involved. If you are connecting to the disks without a backplane or expander solution, you will need the 8i card and SAS breakout cables. Edit: You don't have an expander backplane, so you'll need an 8i (2 x SFF-8087 ports) controller and two SAS breakout cables. Please see: How ...


1

Some years ago I started writing a storage system similar to ceph. Then I discovered ceph and what they had worked better so I dumped my development. During the development process I asked a similar question to yours but on SA I did a lot of calculation on handling lots of small files and found that naming files (assuming they can be anything) by uuid and ...


1

You don't provide the Windows version that you will use. I really recommend using 2012 R2 to get all new feature from NTFS, like hot repair. Your 3 nightmares will be: -Fragmentation -Time taken to do a chkdsk. The time of it is based on number of files, not size. -backup time If you are at least on Windows 2012, you should look at ReFS. This new file ...


1

Apparently, if you set cache=NONE for a disk image file on any host filesystem that does not support Direct IO, Virt-Manager will currently give a not very helpful error message saying "Something something... Invalid Argument" and refuse to start the Guest VM. One example of such a filesystem --that does not support Direct IO-- is the tmpfs. Another such ...


1

When you see disk space being consumed but the files consuming it are not visible in the file system, it usually means the files are being kept open by a running process. The space will be freed once the process is terminated. Rebooting is one way of terminating processes, which is why the space is freed on reboot. You can use lsof to look for processes ...


1

Is it possible to do it in a standalone server Yes, but you don't talk about performance/load requirements, that said I'd pop in a bit more memory if you can, it's cheap enough these days.


1

If you're running powershell 4.0 check our Grant/Revoke-SMBShareAccess http://technet.microsoft.com/en-us/library/jj635705.aspx However, PS4 requires a Win8.1 or Server2012 R2 or later client OS to run. Earlier versions of PS did not have native cmdlets for share ACL modification. I've had good luck with SUBINACL.EXE you can download here ...



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