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Questions tagged [advanced-format]

Advanced Format hard drives use 4 KiB (4096 byte) sectors, instead of the 512 byte sectors used for a very long time. This change has significant impacts on hardware, BIOS/UEFI firmware, operating systems, partitioning tools, boot loaders and even the performance of applications.

One key change is that sector size is now split into two concepts: logical sector size (seen by the OS by default) and physical sector size (visible with extra support in OS and tools). Early Advanced Format drives keep 512 bytes as the logical sector size (termed 512 emulation) with 4 KiB as the physical sector size - but some drives pretend to have a 512 byte physical sector size while actually using 4 KiB internally.

Resources:

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LVM dangers and caveats

I have recently started using LVM on some servers for hard drives larger than 1 TB. They're useful, expandable and quite easy to install. However, I could not find any data about the dangers and caveats of LVM. What are the downsides of using LVM?
Adam Matan
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Upgrading RAID controller to 4kn - do I have to reinitialize the array to use 4kn?

I have an enterprise-grade workstation with an Adaptec 6405E RAID controller in it. According to Adaptec, this RAID controller does not, and will never be able to, natively support 4K disk sectors. If you stick a 4K disk in it, then if it has…
allquixotic
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mdadm and 4k sectors (advanced format)

There are numerous questions on Serverfault about aligning 4k sectors disks, but one thing is not really clear to me yet. I successfully aligned my RAID1+LVM. One of the things I did was use mdadm superblock version 1.0 (which stores the superblock…
Halfgaar
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Where is the overhead for ZFS RAIDZ2 on 4K sector disks going?

I started by creating 16 empty files of exactly 1 billion bytes: for i in {1..16}; do dd if=/dev/zero of=/mnt/temp/block$i bs=1000000 count=1000 &> /dev/null; done Then I created larger and larger RAIDZ2 volumes over the files, forcing ashift=12 to…
steveh7
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Using 4k drives with md/LVM/dm-crypt

I know that I have to align my 4k drives by a multiple of 8 sectors, but what about md-RAID / LVM / dm-crypt? How do I tell these layers that my drive is 4k? If they don't respect the 4k sector size, the partition alignment is useless. How do I…
Vincent
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GRUB hangs before menu, after a HDD upgrade. How to debug?

I have a problem on a server with 4 x 1 TB drives running Debian wheezy and GRUB 1.99-27+deb7u3. sda and sdb have partitions mirrored using (Linux software) RAID1, including /boot. sdc and sdd have a single partition each, mirroring a LVM physical…
Cedric Knight
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How can I set the disk partition alignment using linux tools?

After reading Disk Partition Alignment Best Practices for SQL Server, I just want to give those advices a try, but on my linux test server. What are the required parameters in order to set the partition offset (for fdisk if possible, or any other…
alexandrul
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Does AIX support Advanced Format (4k sector size) SAN LUNs?

I am working with an EMC XtremIO storage array that utilizes SSD devices that use a native 4 KB sector size instead of the traditional 512 B size. I am attaching an IBM AIX 7.1 server to the array. I had trouble getting AIX to assign a PVID to the…
Mike Brickl
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Partition alignment on MegaRAID RAID 1 with 4k sector (advanced format) drives

I want to setup RAID 1 (mirroring) on a LSI MegaRAID SAS 8708EM2 (1078 chipset) with 4k sector (advanced format) drives. To the best of my knowlegde the controller does not officially support 4k sector drives whereas the newer 9xxxx series…
georg
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ZFS (NexentaStor) and 4k Advanced Format Partition Alignment

I have a storage system that contains 8 x 1TB drives that use the 4k sector size "Advanced Format". I'm planning to run NexentaStor on this hardware and want to ensure that I'm taking the 4k sector size into account. Is there anything special I need…
ewwhite
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Exposing disks to virtual machines as 512e

I'm aware that VMware ESXi supports the creation of datastores on local Advanced Format 512e disks as of v.6.5. However, all the (very scarce) information I can find seems to suggest that virtual disks created on that datastore will still be…
Kevin
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aligning truecrypt partition on 1.5TB 4kB sector drive

Aligning partitions to start at real physical sector of ssds / stripped raids / 4kB drives is a 'good thing to do', but I've run into a problems when trying to do it for a truecrypt partition that will contain ext3 on it. Or so it seems. When drive…
pQd
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Extremely Low Random Read/Write Performance on (4096 Aligned) Advanced Format Disks

On a SATA 3.0, 6.0 Gb/s *-disk:0 description: ATA Disk product: WDC WD20EFRX-68E vendor: Western Digital physical id: 0 bus info: scsi@1:0.0.0 hw_sector_size: 512 logical_block_size: 512 physical_block_size:…
Gaia
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How to make partition, raid5 and filesystem on 6x2TB WDC-drives in Linux

I'm getting confused by this "Advanced Format" (4KB sectors) talk of bigger (2TB) drives - and I am wondering about how I would resolve this if I'm building a new software (mdadm) RAID-5 array. The drives I'm gonna buy is the Western Digitial…
jorno
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Using a surveillance drive in a Web Server

Would there be any concerns about using a Surveillance/DVR, Advanced Format drive in a Linux Web Server. Only wondering because I have 2x 1TB Seagate Video drives here that are now collecting dust and I need 2 hard drives for a server. So it would…
user364794
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