Disk storage is generally the permanent data storage of a server.

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34
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6answers
3k views

Is my Hard Drive Failing?

I just tried to run a test on my hdd and it doesn't want to complete a self test. Here is the result: smartctl --attributes --log=selftest /dev/sda smartctl 6.2 2013-07-26 r3841 ...
0
votes
0answers
19 views

External USB drive on xen windows guest

I have an external USB 2Tb drive I'm trying to use with a xen guest. Xen Center 6.1 sees the drive in the removable storage repository and I can assign it to a guest. But the guest (tested ...
1
vote
2answers
29 views

What is the difference between truss -D and truss -E?

I am currently analyzing a command on Solaris that reads from a file and has very low performance. The truss -D commands shows me read system calls taking up to 0.03 seconds, but when I use truss -E, ...
0
votes
1answer
26 views

What is the counter type for Linux's /sys/block/$DEVICE/stat

What are the counter types for /sys/block/$DEVICE/stat? $ cat /sys/block/sda/stat 8323741 42381356 464031898 19207478 1940738 49062039 408122282 79935459 0 22315734 99172579 Specifically, ...
0
votes
1answer
27 views

PostgreSQL queries slower than before?

I am using PostgreSQL 9.3 server on my production server. Everything had been working fine for the past couple of months. But since the past week or so, PostgreSQL seems to have becomes very slow with ...
6
votes
3answers
457 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 ...
0
votes
0answers
44 views

How is it possible for reallocated sector count to decrease?

The reallocated sector count of a disk in a RAID array has been increasing over the past 6 months, but now it seems as though the reallocated sector count has decreased. A month ago (according to ...
0
votes
0answers
59 views

Azure disk performance

I am running on-demand, research D14 instance in Azure South Central US region, with a 4-disk RAID0. Recently the disk performance has become unusably slow, particularly the RAID performance, which is ...
0
votes
1answer
19 views

What is counted as an I/O Operation?

What is counted as an IOP? Is one IOP one file read or written or one block (e.g. 4KB) read or written? Or something else?
0
votes
0answers
29 views

Linux quota - wrong disk usage

I'm using centos 6 and quota shows wrong disk usage for all users... Something like multiply real disk usage... # quota -v myuser Disk quotas for user myuser (uid 511): Filesystem blocks ...
0
votes
1answer
36 views

Why my AWS volume size is different from the actual size?

It's very wried to see my actual disk size is much less than the actual size. From the information, looks this disk is not be partitioned. I have no idea why the actual size is 20G but disk size is ...
2
votes
3answers
59 views

Accessing multiple disks under single virtual partition?

I have disks as below on my Debian server: /dev/sda1 276M 29M 233M 11% /boot /dev/sdb1 917G 793G 79G 92% /home /dev/sdc1 1.8T 1.7T 79G 96% /home2 /dev/sdd1 1.8T 1.7T 79G 96% ...
1
vote
0answers
45 views

Are /dev/disk/by-id symlinks unreliable?

I am provisioning a Nova server and Cinder volumes using a Heat template. In order to identify the Cinder volumes attached to my OpenStack server I would like to use the /dev/disk/by-id/... symlinks ...
1
vote
1answer
81 views

How to reacreate the EFI partiton and mirror and existing system partition of an GPT disk?

I have the following setup (very well possible that this is no good practice but it is the given situation): There were 2 x 3TB dynamic GPT disks in a Windows server, Disk0 with EFI (~200 MB), System ...
0
votes
1answer
50 views

How to generate random files and directories that are scattering across the whole partition? [closed]

I want to perform a heavy test of using "resize2fs" to shrink the file system. Currently, I have script that creates a few hundred thousand files taking several hundred GB. But it doesn't take very ...
36
votes
10answers
2k views

Linux on VMware - why use partitioning?

When installing Linux VMs in a virtualized environment (ESXi in my case), are there any compelling reasons to partition the disks (when using ext4) rather than just adding separate disks for each ...
5
votes
3answers
89 views

Shared Disk in modern data center (SAN, virtualization, etc)

I'm a developer...treading here on foreign terrain. Please pardon any naivete. I work on an application that stores data both in a database and the filesystem. Context: Clustering and Network ...
0
votes
0answers
55 views

Unclaimed disk space but no actual physical disk present

I am working with Ubuntu server 12.04 and earlier this week we detected a bad disk in /dev/sdl. I was not able to query its mount point and it also had failed SMART tests. Today I brought a brand new ...
4
votes
1answer
146 views

HDD is acting up, but S.M.A.R.T says everything is fine

Before I begin, a quick disclaimer. I'm basically a developer forced into a sysadmin role by circumstances, so I apologize in advance if I say something stupid or seem like I don't know what I'm ...
1
vote
1answer
110 views

Hard drive error message in Virtual Root Server

After noticing a high load on our virtual root server (2 x 1 TB RAID 1 Subset) I have found these messages in /var/log/messages (CentOS): kernel: ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action ...
4
votes
3answers
1k views

Why do servers have SAS instead of SSDs? [closed]

I was wondering why do servers still come with SAS disks instead of SSD disks? I know that SAS are faster than normal hard drives but they are still much slower than SSDs. I think they are more ...
0
votes
1answer
435 views

SCOM alert: The threshold for the Logical Disk\Avg. Disk sec/Transfer performance counter has been exceeded

We are monitoring several Windows Server 2012 R2 VMs running on Hyper-V. Now SCOM (2012 R2 UR2) reports: The threshold for the Logical Disk\Avg. Disk sec/Transfer performance counter has been ...
0
votes
1answer
50 views

Tracking down rogue disk usage

I found several other questions regarding the theory behind my problem (e.g. this, this), but I don't know how to apply the answers to my machine. # du -hsx / 11000283 / # df -kT / Filesystem ...
-1
votes
2answers
77 views

iostat reporting low r/s on first line for specific disk, expected r/s on all following lines for that same disk

When copying data from hard disk sdc to sda, I notice that the number of read requests completed per second was unusually low: $ iostat -x 1 1 Linux 3.13.0-32-generic (melancholy) 2014-08-15 ...
1
vote
1answer
70 views

Extract data from server without causing high disk IO

My current diagnosis is that there is a hardware fault, either related to the memory of the hardware RAID controller or something related to the extra juice the hard drives requires when running on ...
-1
votes
1answer
155 views

How to access a system with write permission after file system check fails?

I created three new partitions, but after a reboot, the system is being dropped to a shell: /dev/mapper/group-newpartition: clean, 11/655360 files, 276620/2621440 blocks [FAILED] An error occurred ...
3
votes
3answers
207 views

Power down disk array

I have a Supermicro server with an external disk array connected using SAS. Assuming I have already shut down the server properly, is there anything I should do before I can power down the disk array ...
0
votes
1answer
39 views

How to alleviate high disk reads on server?

We are currently hosting a 3TB library of image galleries on our web server, all searchable by users. With about 400 active users at a certain time on the website, our disk reads are pushing 100% I/O ...
0
votes
0answers
54 views

100% disk usage Windows server 2008

We have HP Proliant G6 server with 4 1.5Tb SATA disks. 2 RAID 1 arrays and 2 logical drives 1.5Tb. One day ago I mentioned twith resmon that disk usage is 100% and i\o speed is not more then 4Mb\s ...
-1
votes
1answer
2k views

Can't mount disk (VFS: Can't find ext4 filesystem)

Tried to mount a disk (hardware raid) but failed. #mount -t ext4 /dev/sda /data mount: wrong fs type, bad option, bad superblock on /dev/sda, missing codepage or helper program, or other ...
0
votes
2answers
75 views

Measuring disk usage

What is the fairest unit to determine the disk usage (except the total storage usage e.g. in GB)? IOPS? Bytes read / write? Bytes transferred over network (would be equal to Bytes r/w)? Other? And ...
0
votes
1answer
48 views

How to create two partitions with same size?

I created two partitions using the following commands. parted /dev/sda --script -- mkpart primary 1 50001 parted /dev/sda --script -- mkpart primary 1948001 1998001 Each partition should have 50001 ...
3
votes
3answers
736 views

input/output error at clean ext3 partition - how to check what wrong with data block

I have a problem with a file at a ext3 partition on CentOS 5 server (kernel version 2.6.18-164.15.1.el5) with a HP Raid Controller: hpacucli ctrl all show detail Smart Array P410 in Slot 1 Bus ...
0
votes
0answers
299 views

XenServer 6.2 Read Only and Slow Disk I/O

I virtualized a datacenter a few months back and we have a pool of 3 HP DL360 G5 servers, each with 32GB of Memory and dual Intel Xeons. Recently we have been experiencing 2 issues, the first of which ...
18
votes
2answers
410 views

An unknown tool is wiping our Virtual Machines and we can't ID it

A console view of a Windows 2008 R2 VM, on vSphere is showing the following screen: "Operation 2 of 2" "Wiping disk" Can someone advise on what this program is? Some information on this mystery: ...
0
votes
1answer
195 views

How does loss of DWORD synchronization affect the health of an SAS disk?

I tried to get more information from the error log of an SAS disk by running the following command that prints values and descriptions of the SAS (SSP) Protocol Specific log page. # smartctl -d scsi ...
3
votes
1answer
945 views

No space left on device - wrong size

I'm running an FreeBSD dedicated server. I am getting messages that I have ran out of space on the device. df -h is saying that I have no space left but du -sh /* doesn't even show the directiories ...
0
votes
2answers
111 views

Unreasonable performance expectations for RAID 0 performance?

This is my first time building a machine with a hardware RAID card. We bought a Dell T620 with the H710P RAID controller (1GB NV Cache), a 160GB Solid State Drive (SATA Read Intensive MLC 3Gbps), and ...
0
votes
0answers
122 views

Have to keep resetting quota for user on CentOS 6.5 while using VirtualMin

I have VirtualMin installed on a development server running CentOS 6.5. None of the users have explicit quotas, yet periodically I get write issues when running as that user. If I run as root, I have ...
0
votes
0answers
27 views

poweredge 1950 iii disk options

I have a pair of poweredge 1950 iii boxes which I use for a VMware lab. They are loaded with 64 gb of ram (I discovered that this is actually supported), a pair of quad core cpus, and a pair of 300gb ...
1
vote
1answer
46 views

Can I convert a production disk to Dynamic?

I have a server that is running out of disk space on a partition. I can't expand to the partition running out of space because the disk is not dynamic? From computer manager can I convert the disk to ...
1
vote
1answer
27 views

Obtain an offline image of an Xserve disk

We have an Intel Xserve with Mac OS X 10.4. It seems to have been infected by a virus. We want to obtain the disk image without booting into the OS. Preferably, we would want to boot via a USB disk ...
12
votes
7answers
1k views

How do storage IOPS change in response to disk capacity?

All other things being equal, how would a storage array's IOPS performance change if one used larger disks. For example, take an array with 10 X 100GB disks. Measure IOPS for sequential 256kb block ...
3
votes
1answer
78 views

Can I rely on scsi host numbers to always stay the same?

I want to detect whether a disk is attached to the correct sata-port. While lsscsi gives me some useful information about the used host, I was wondering whether the SCSI host number will always stay ...
1
vote
1answer
294 views

Identify disks in vCenter to partitions in Linux guest

What I am trying to accomplish is to correlate hard drive in vCenter to the disks in the Linux guest. So here it goes Opening up settings for the guest in vCenter and moving to hardware tab, shows ...
2
votes
0answers
87 views

actual disk iops and write merging

/dev/sdb has LVM and exposes a single logical volume, dm-0. While writing to dm-0, /proc/diskstats reports: # of writes completed sdb 29646717 dm-0 131315099 # of writes merged: sdb 101668283 dm-0 ...
0
votes
1answer
381 views

Linux - KVM - very slow disk io

The I/O performance of my new server is pretty low. I Googled and tried everything I can imagine. First of all, here are the Hardware Components: AMD Opteron(tm) Processor 6344 4x Seagate ...
3
votes
1answer
106 views

Why are cgroups (blkio serviced bytes) and iotop producing diverging results

I work with lxc user space tools on ubuntu 14.04 and I want to perform some stress tests and benchmarking within a container. I know that free and htop are not working properly in a container. I am ...
0
votes
0answers
79 views

Backup server (System Center 2012 DPM Admin Console) Disk Missing

My backup server was recently powered off by an employee who was unaware of what they were doing. When I powered it back on, I entered the admin console to see that all of the volumes that were ...
0
votes
0answers
1k views

Ubuntu 14.04 disk utility SMART self-test failed threshold not exceeded

I'm using the "Disks" program in Ubuntu 14.04 (live DVD) to assess the health of a drive I suspect is failing. However, when I first opened the program, it showed that the overall health was OK and ...