Questions about hard disks' performance, issues, tips, and software.

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Use of 2.5" Laptop Drives in a Server?

We're acquiring several 1U servers with (8) 2.5" drive slots. Although we can use either SATA or SAS, there is a large price variance as soon as you order 16 or 24 of these drives, so we are looking ...
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votes
7answers
29k views

how to use a disk with high reallocated sector count?

After 3 years in 24x7 service a 1TB Seagate Barracuda ES.2 enterprise drive is showing signs of failure. S.M.A.R.T. reallocated sector count is high. Wikipedia article suggests that the drive can ...
6
votes
3answers
714 views

Is disk serial readable from supermicro chassis?

We are working with a hosting company for managing our dedicated servers. We asked for a replacement disk on one of the servers by providing the serial number. They took out 2 other disks instead and ...
6
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6answers
6k views

How can I tell what's spinning up my drive?

I have enable "spindown" on one of my Linux server's drives, which is only accessed by a BitTorrent client - meaning, when I don't have torrents running, nothing else should be accessing the disk and ...
6
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7answers
1k views

Laptops - RAM vs Disk for performance

In the perfect world I could get everything I want, however budgets for new laptops are low so I normally can get a user a laptop + additional RAM (to at least 4Gb). This has been mostly motivated by ...
6
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2answers
28k views

How do I mount sub-directory to a hard drive in Linux?

Let us assume that I have two hard drives (A,B) and have the following directories: /var/www /var/www/upload Currently if I upload a file to /var/www OR /var/www/upload ; it will be saved in drive ...
6
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5answers
591 views

Why do they use laptop form factor HDD's for storage servers?

The storage servers I've seen generally use 2.5" drives instead of 3.5" drives. In my experience the larger drives have better capacity, speed, and durability. Why are the smaller ones favored in ...
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4answers
7k views

Disable Caviar Green drives spinning down

A few months ago I build a 1u server to go into a colo facility. Not knowing any better, I used WD Caviar Green drives. My users have been complaining that the system can be a little slow off the ...
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5answers
4k views

SW SSD Raid 1 over HW RAID 10

A provider(data center) recommended I go with 1TB SSDs in a software RAID 1 over HW RAID 10 with mechanical drives. Their quote: Typically SSDs are most reliable than RAID cards and since you ...
6
votes
2answers
451 views

Could SpinRite possibly be messing up my laptop hard drives?

Context: We have a midsize business with a few dozen laptops. Whenever we get one in because someone leaves or gets an upgrade, standard procedure is to zero and then run SpinRite (level 4) on the ...
6
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2answers
8k views

I used “dd” to clone a drive to a larger drive. How can I leverage the additional space (linux)?

Fdisk can't see extra space I upgraded my trusty 74gb Raptor hard drive to a 600gb Velociraptor behemoth. I used "dd" to clone the drive, (i.e. "dd if=old-drive-device of="new-drive-device), swapped ...
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4answers
2k views

Server 2008 R2 requires 2 disks to boot

Weird one. I have a domain controller with Server 2008 R2. It is a hack job but is reliable. AMD system. AM2 6000+ Asus Crosshair MB. The server is utilizing 5 Sata ports for Hard disks of assorted ...
6
votes
1answer
2k views

No space left on device — but there is space

I'm running an Ubuntu 12.04.1 server in a VMware virtualized environment that has a strange issue. Twice now, at seemingly random times, the machine has suddenly been unable to write to the root ...
6
votes
7answers
5k views

lvremove claims LV to be open

frequently I notice that after a $ sudo lvcreate vg -L 10G immediately followed by a $ sudo lvremove vg/<created volume> I get the error message Can't remove open logical volume "..." ...
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2answers
4k views

How long should rebuilding 250GB take? [closed]

In a PowerEdge 1900 have I a hardware RAID 5 of 5x250GB disks + 1 hot spare 250GB. Disk 2 have errors, so I forced it offline in the raid bios to replace it. Now it have been rebuilding to the hot ...
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5answers
7k views

Postgres DISK IO very high. What can I do to reduce it immediately?

I'm aware faster disks than what I'm using will help but this will take longer to put in and I am trying to use some emergency measures to decrease disk IO. atop is reporting DSK usage on the red ...
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3answers
2k views

Server System drive on a USB stick? Good? Bad?

This is a follow up to this question. I am assembling a storage server with 14 SATA drives. I don't want to "waste" a drive for the OS system, so I thought I could isntall and run the OS from a USB ...
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4answers
4k views

What is the difference between SAN Hard Drives and Normal Hard Drives?

At work, we have decided to finally virtualize and have decided to upgrade out SAN setup with higher capacity Hard Drives. However, what exactly is the difference between Hard Drives that come ...
6
votes
4answers
485 views

mdadm: Replacing array with entirely new drives

I have a server with three 500GB drives, with most of my data in a RAID5 configuration spanning the three of them. I just purchased and installed four 1TB drives, and the intention is to move off of ...
6
votes
4answers
218 views

Crashing my disk using Java

I have a Java program that must do the following 3 things: Download a file from a website. Run the file trough testA and testB (both in java) Delete the file and save the test results on the disk. ...
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3answers
3k views

Linux different size for df and du for root partition

On my CentOS server, both of the commands are showing different usage for disk / , df shows this output: Filesystem Size Used Avail Use% Mounted on /dev/xvda2 16G 14G 952M ...
6
votes
1answer
150 views

How to prevent IO Load under Linux for Video serving?

I'm currently serving videos of conferences via Nginx on 3 servers; 4 cores, enough memory (no swap used) and RAID-10 with 8 drives per server. Unfortunately iostat -xd 1 gives me 100% on all 3 ...
6
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3answers
6k views

Is it safe to transfer RAID 5 disks from one server to another?

I have (what I assume) will be a relatively simple question. I have an old file server that I've decommissioned and replaced. I would like to re-use the hardware from the old file server at our ...
6
votes
3answers
8k views

Is it wise to use SSHDs (Solid state hybrid drives) on a server?

I have a bunch of servers with very heavy I/O that currently use SATA3/SAS drives, but do suffer from I/O wait on the SATA drives, and I have just been alerted to the existence of SSHDs which cost the ...
6
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3answers
1k views

Hard Drives: Always on or spin up/down as needed?

The specific application is a NAS that hosts media content and is frequently accessed during the day. My NAS was probably cycling on and off around 5 times a day so I decided to not allow it to spin ...
6
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3answers
7k views

Which is better, Split or Monolithic VMware disk in a production enviroment?

Ok, so I have read a bunch of material on-line and curious as to your thoughts on split vs monolithic disk in a production environment. We are going to be building the VM server on a server that has ...
6
votes
2answers
4k views

How to determine which file/inode occupies a given sector

I received messages in /var/log/kern.log that indicate drive failure. The messages occured while copying my $HOME between drives (ext4 -> ext3): [ 5733.186033] sd 4:0:0:0: [sdb] Unhandled sense code ...
6
votes
4answers
256 views

Frequently accessed files and I/O usage

I'm curious, from a performance standpoint, is there an advantage in storing all files in one directory versus having each file in a separate directory? I'm not concerned about organization. Also, ...
6
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2answers
3k views

Hadoop disk fail, what do you do?

I would like to know about your strategies on what to do when one of the Hadoop server disk fails. Let's say, I have multiple (>15) Hadoop servers and 1 namenode, and one from 6 disks on slaves ...
6
votes
3answers
186 views

How bad is it to use a virtual file system with VMWare?

IT is running a series of VMs that we'd like to see optimized further: if the VMs' are Windows XP, storing their NTFS images out to the virtual disk (ext3) provided by Linux/VMWare, how much of a hit ...
6
votes
1answer
4k views

Does Dell Permit 3rd Party Hard Drives on Perc 6/i?

I have various Dell servers (all 2950's) I would like to put some SSDs in. I have spoken to Dell on the phone and asked for a quote for 128GB SSDs for 2950's, they told me they don't sell them for ...
6
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4answers
2k views

My linux server takes more than an hour to boot. Suggestions?

I am building a CentOS 5.4 system that boots off a compact flash card using a card reader that emulates an IDE drive. It literally takes about an hour to boot. The ultra-slow part occurs when Grub ...
6
votes
1answer
291 views

zfs checksum error in raidz1 vdev but not in disk

I am backing up data stored in a zpool consisting of a single raidz vdev with 2 hard disks. During this operation, I got checksum errors, and now the status looks as follows: pool: tmp_zpool ...
6
votes
3answers
41k views

Reinserted a RAID disk. Defined as foreign. Is import or clear the correct choice?

I have re-inserted a RAID disk, on a DELL server with Windows Server 2008. The drive-status indicator was changing between a green and amber light, and the monitor gave the following message: ...
6
votes
1answer
2k views

Is there way to read sectors from SATA drive without ECC correction?

I know, there was such possibility like that in old ATA standards: "READ LONG" command produced LBA sector + ECC payload. sg_read_long supports in in linux, but the command is obsolete for quite a ...
6
votes
2answers
7k views

Dell PERC 4 (PowerEdge 2850): Unresolved configuration mismatch between disks(s) and NVRAM

We had an extended power outage (almost four hours); now I have a Dell PowerEdge 2850 server which is giving me this error (from a PERC 4e/DI) on boot up: All drives are listed in the PERC ...
6
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9answers
3k views

2 drives, slow software RAID1 (md)

I've got a server from hetzner.de (EQ4) with 2* SAMSUNG HD753LJ drives (750G 32MB cache). OS is CentOS 5 (x86_64). Drives are combined together into two RAID1 partitions: /dev/md0 which is 512MB ...
6
votes
4answers
8k views

3.5“ 15k RPM drives vs 2.5” 10k RPM drives

How do 2.5" 10k RPM SAS drives perform compared to 3.5" 15k RPM SAS drives? Specific areas of comparison: Random write Random read Sequential write Sequential read
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votes
16answers
4k views

What are some free utilities for securely wiping data from a floppy disk? [closed]

I have a stack of old floppy disks in my server room and before disposing or donating them, I want to make sure they are cleaned. Can anyone suggest some free utilities (Windows or Linux) for securely ...
5
votes
7answers
559 views

Windows drive letters A: and B:

This is a question that just popped into my mind and I can't help but wonder why it's still common for a Windows installation to be installed on C: with all other drive letters going up from D: to Z:. ...
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12answers
27k views

SQL Server database on an external hard disk drive

Due to some security problems, My boss has asked me to store all sensitive data in external/removable storages like USB stick or external HDD and this specially includes the MDF/NDF/LDF files of SQL ...
5
votes
4answers
12k views

Performance differences between 2.5“ vs. 3.5” SAS

What real performance gains/losses are there on 2.5" vs. 3.5" 15k SAS drives. Are folks really seeing seek differences, &c?
5
votes
5answers
951 views

Linux: how many disk I/O does it take to read a file? How to minimize it?

According to this paper on Facebook's Haystack: "Because of how the NAS appliances manage directory metadata, placing thousands of files in a directory was extremely inefficient as the ...
5
votes
4answers
5k views

Maximum safe hard drive temperature?

I have two new-ish 1TB hard drives in my server, both running at 38 degrees C at the moment. Should I be worried?
5
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2answers
6k views

RAID 5 with big SATA disks. Do or don't?

Is it sane to build a machine with RAID 5 expecting to hold around 5 Tb (and able to grow) with 1.5 or 2 Tb SATA II disks? It will be used as audio and documents storage. I already have chosen a ...
5
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8answers
11k views

Can you use your own drives on Dell PowerVault MD3000i?

I would like to use my own drives in the Dell PowerVault MD3000i. Does anyone know if you are able to? We are looking at different SANs for our VM farm and would rather be able to replace a drive in ...
5
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8answers
8k views

Hard Drive Speed: RPM vs. Cache

When trying to choose a SATA magnetic hard drive (not SSD) for high performance for both random and linear access, which should be the primary factor? For example: would a 10k RPM drive with 16MB ...
5
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3answers
2k views

Problem with slow hard disk

We bought some new PCs in my company with the new iCore 7 and 8GB memory and the following hard disk: WESTERN DIGITAL WD8000AARS 800GB CAVIAR GREEN SATA2 The problem we have is that after installing ...
5
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4answers
4k views

Is it normal for a SAS drive to have a few bad blocks, or should I replace my drive ASAP?

I have a drive—part of a RAID 1 mirror—that has two bad blocks. Adaptec Storage Manger e-mailed me when it detected the blocks. It shows 4 medium errors for that drive, but state is still “optimal”. ...
5
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6answers
17k views

What is the recommended temperature range for a hard drive?

What is the best temp to keep harddrives running in? I have harddrives that keep failing due to the temp being to high.