1
vote
1answer
41 views

How to find the true disk usage on my Linux box?

I have a linux box on my school's server. When I was trying to install Protocol Buffers, disk usage is reported as exceeded. So I checked my disk usage by two command on my home directory: du -h ...
1
vote
2answers
52 views

Disk on key is read only on every computer

I have a 16 GB SanDisk Cruzer Blade Disk-on-key. After a few days of use, it has become write-protected/read-only. When I plug it in, you can see this in my Ubuntu's dmesg: [ 819.003359] usb 2-5: ...
2
votes
4answers
119 views

What is the /dev/disk/by-uuid/ and why does it use all free space on the disk

I have the following Debian that works in Virtual Box: $ uname -a Linux debian 3.2.0-4-amd64 #1 SMP Debian 3.2.51-1 x86_64 GNU/Linux Recently I notice that I don't have any free space: $ df ...
5
votes
2answers
149 views

How to create a fixed size Linux ramdisk which does never swap to disk?

I want to create a fixed size Linux ramdisk which never swaps to disk. Note that my question is not "why" I want to do this (let say, for example, that it's for an educative purpose or for research): ...
3
votes
2answers
41 views

Uniquely identifying a drive (not a partition)

I'm writing some automation scripts for full disk backups and I'd like to be fairly precise with which devices are used. I know that one can uniquely identify a partition using UUIDs and blkid, but ...
0
votes
1answer
45 views

How to create memory-based disk in linux? [duplicate]

I need to have a very fast disk for keeping cache. How can I do that in Linux?
6
votes
4answers
443 views

Given a kernel ATA exception, how to determine which physical disk is affected?

I woke up this morning to a notification email with some rather disturbing system log entries. Dec 2 04:27:01 yeono kernel: [459438.816058] ata2.00: exception Emask 0x0 SAct 0xf SErr 0x0 action 0x6 ...
2
votes
1answer
160 views

Difference between “blockdev --flushbufs” and “sync” on Linux?

Is there a difference in practice between running blockdev --flushbufs and sync(1) on Linux? (apart from blockdev flushing for a specific device, and sync being system-wide). sync(1) manpage says it ...
1
vote
0answers
113 views

How different is I/O handling of hard disk in AIX and Redhat Linux?

I am running a hadoop I/O workload in redhat linux and have ran that in IBM AIX as well with same underlying hardware, disk and disk configuration. With the default settings on the os redhat linux is ...
1
vote
1answer
230 views

How to measure total disk I/O per hour

I have a cloud server were we get billed also for disk IO usage. Here is an example from the stats: 04/Sep/2013 07:24:19 04/Sep/2013 08:24:19 0,5 GB / 1 vCPU (0,08 Kr. per hour): Charge for ...
11
votes
2answers
407 views

How to detect if a disk is seeking?

I can use a variety of tools to measure the volume of disk I/O currently flowing through the system (such as iotop and iostat) but I'm curious if it's possible to easily detect if a disk is seeking a ...
6
votes
4answers
260 views

Are short-lived files flushed to disk?

My program creates many small short-lived files. They are typically deleted within a second after creation. The files are in an ext4 file system backed by a real hard disk. I know that Linux ...
6
votes
2answers
259 views

Creating formatted partition from nothing

I need to create filesystem with just one partition from nothing (/dev/zero). I tried this sequence of commands: dd if=/dev/zero of=mountedImage.img bs=512 count=131072 fdisk mountedImage.img n ...
10
votes
3answers
601 views

How to get total number of bytes/sectors/blocks written to disk since booting?

I'm considering and update from HDD to SSD. But since Flash cells can only sustain limited writes. I want to know how much data my computer write during normal operation. So I can determine how long ...
1
vote
2answers
224 views

Setting up a RAID 1 in Funtoo [closed]

In short Following the guide How to Set Up a RAID 1 Under GNU/Linux, I have setup a RAID 1. Checking the RAID Array for validity in various ways, appeared to be normal. However, after rebooting the ...
1
vote
2answers
52 views

Create my own disk server

I have been wondering how all these small nas boxes that run linux can share over network and usb. The network part is totally under control, but I am completely at a loss on how I could hook up a ...
3
votes
2answers
180 views

How do I refresh the magnetic state on a disks with backups?

I have a couple of large disks with backup/archive material on them. They're ext4. Regarding the ones of those that will be stored for a couple of years without reading the whole disc again I've been ...
1
vote
1answer
235 views

How to realign a disk on logical volume with minimum to zero down time

A system running un-align disk partition that needs to be aligned without loss of data on all the partition including mbr with the minimum to no down time.
3
votes
1answer
907 views

What's the easiest way to decrypt a disk partition?

I made a mistake of encrypting the entire LVM physical volume (contains both home, root, and swap) when installing a CentOS 6.4 (2.6.32-358.6.1.el6.x86_64) box. I soon came to realize that moving ...
1
vote
1answer
118 views

Keeping disk caches when hibernating

Is there a way to keep disk caches when hibernating Linux? I understand and agree that dropping them is the best option all-around. But my system is unresponsive after resume and I would like to give ...
1
vote
1answer
84 views

Really umount external drive

I had a USB drive mounted on /dev/sdb1 and I want to reformat from NTFS to ext3. I did umount -l which unmounted the disk. I deleted the old partition using cfdisk. I ran mkfs.ext3, but got the error: ...
13
votes
8answers
4k views

How to determine which sd* is usb? [duplicate]

Possible Duplicate: How to know if /dev/sdX is a connected USB or HDD? The output of ls /dev/sd* on my system is - sda sda1 sda2 sda3 sda4 sda5 sda6 sda7 sdb sdc sdc1 sdc2 ...
4
votes
1answer
5k views

/dev/sdb: No such file or directory (but /dev/sdb1 etc. exist)

I'm not sure what is wrong here but when running fdisk -l I don't get an output, and when running fdisk /dev/sdb # I get this fdisk: unable to open /dev/sdb: No such file or directory I'm ...
27
votes
7answers
35k views

How can I monitor disk io?

I'd like to do some general disk io monitoring on a debian linux server. What are the tools I should know about that monitor disk io so I can see if a disk's performance is maxed out or spikes at ...
2
votes
3answers
87 views

Single machine with two disks

I have two disks on my local computer, so when you write to these disks simultaneously, are changes writting to them serially or in parallel?