2
votes
0answers
43 views

Reduce cache size of flash storage devices

For various benefits Linux uses a memory cache for writes to removable stogare devices like memory sticks. This cache seems to be quite large on my system, which leads to some annoying behavior. For ...
2
votes
0answers
36 views

SSD seems full, but file system says otherwise [duplicate]

I'm running CentOS and have a 100GB Micron RealSSD P300. It appears that the drive is almost full, as noted by running df: Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda3 ...
1
vote
1answer
42 views

How to use one nic for storage traffic & other for network traffic in Linux(Slackware)?

Problem I have a Linux machine (Slackware) with two network interface cards and i want to use one interface for network traffic and other for storage traffic . As this is Slackware i dont know this ...
1
vote
1answer
63 views

Is it possible to manually manage a Solid State Hybrid Drive?

I'm about to buy a new laptop which has a SSHD. It stands for Solid State Hybrid Drive, which means it has a big, regular HDD with a small, usually 8GB SSD to cache frequently accessed files. Now ...
1
vote
0answers
189 views

I can't find tape device file inside /dev directory

I'm using tape storage drive HP LTO3 1x8 auto-loader which is connected to my server running CentOS. it is detected in CentOS correctly. cat /proc/scsi/scsi Host: scsi2 Channel: 00 Id: 01 Lun: 00 ...
3
votes
1answer
99 views

Something like VMware “Changed Block Tracking” (CBT) in linux

I'm wondering if is there any possibility to track changed blocks in linux with an ext3/ext4 filesystem (or a specific one supporting it). I mean a feture like the Changed Block Tracking (CBT) ...
1
vote
1answer
326 views

Qlogic HBA issue

We have running server with attached SAN storage and everything was fine. However last week we moved our server blade to a new chassis. Everything is same, we just add new WWN in Brocade SAN switch to ...
0
votes
2answers
171 views

Does configuring iscsi target and iscsi initiator in two linux nodes and using ethernet cable for communication make it SAN?

I'm using freeNAS to share an extent via iSCSI to my another Linux box using Ethernet cable. It work as a block storage. So SAN work as a block storage. Now, in my scenario is it working as a NAS or ...
1
vote
0answers
98 views

Mount an SD card over USB?

I'm currently using: insmod g_file_storage.ko file=/dev/mmcblk0p1 stall=0 removable=1 This works as I can see the device in Windows. However when it comes to changing a file, the changes are not ...
4
votes
2answers
121 views

Can you identify transport via sysfs?

I'm writing a script, and I'm interested in being able to identify the transport class (fc - "fibre channel", scsi, iscsi, etc.) for a given block device. I can retrieve this information via ls -l ...
1
vote
1answer
792 views

Linux EMC scan Lun not working

We have CX4-120 EMC SAN storage, I expend existing LUN size to 20GB but now i am not able to see any cylinder changes on host fdisk -l output. Following command i am running to re-scan my hda or LUN ...
0
votes
2answers
265 views

Should I change SSD?

Demsg shows this EXT4-fs error (device sda1): ext4_ext_get_blocks: inode #7743113: (comm flush-8:0) bad extent address iblock: 3503, depth: 1 pblock 0 EXT4-fs (sda1): delayed block allocation failed ...
1
vote
1answer
177 views

can linux be configured to blink an LED (GPIO) on disk activity?

I'm hoping to blink an LED that is wired up to a GPIO line whenever the USB connected disk has activity is there an easy way to pull this off?
0
votes
1answer
128 views

Can we create lvm volume group with mapped device?

I can create a lvm volume group with a loop device. But if I use dmsetup to map the loop device into several devices, then I can't create a lvm group with /dev/dm-. Why is it not possible to create ...
3
votes
2answers
278 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 ...
10
votes
1answer
2k views

How do pdflush, kjournald, swapd, etc interoperate?

Recently saw a question that sparked this thought. Couldn't really find an answer here or via the Google machine. Basically, I'm interested in knowing how the kernel I/O architecture is layered. For ...
5
votes
3answers
2k views

What is the best practice for adding disks in LVM

According to the Linux manpages you can add raw disks as well as partitions to a volume group. In other documentation (RedHat, CentOS or openSUSE), all examples refer to adding partitions to the VG ...
2
votes
1answer
4k views

extending a partition by resize2fs

I have a 4 GB SD card. Before the image load root@ubuntu# fdisk -l Disk /dev/sdb: 3965 MB, 3965190144 bytes 49 heads, 48 sectors/track, 3292 cylinders, total 7744512 sectors Units = sectors of 1 * ...
1
vote
0answers
144 views

iSCSI on startup

I've configure iSCSI but CentOS 6.3 is unable to recognize if on startup. Here is fstab config: /dev/sdb1 /home ext4 _netdev 0 0 Here is iscsi.conf ...
3
votes
5answers
10k views

Finding all storage devices attached to a Linux machine

I have a need to find all of the writable storage devices attached to a given machine, whether or not they are mounted. The dopey way to do this would be to try every entry in /dev that corresponds ...
2
votes
1answer
382 views

Trapping “READ FPDMA QUEUED”

Recently I encountered a kernel message: ata3.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 ata3.00: irq_stat 0x40000008 ata3.00: failed command: READ FPDMA QUEUED ata3.00: cmd ...
1
vote
1answer
329 views

Do I need ephemeral storage?

I was running a small instance on Amazon EC2. I'm trying to migrate it to a micro as it requires very minimal processing power. One thing I just learned though, is that micro instances do not come ...
2
votes
0answers
180 views

How do create an encrypted system with multiple Linux distributions?

A few weeks ago I created a completely encrypted system on a notebook and must say I like the idea. It's a little bit annoying to enter the password on every boot, but it's nice to know even if I ...
3
votes
3answers
2k views

ReFS but for Linux

Microsoft is going to bring a "Resilient FileSystem" with Windows 8, but only for servers. I'd like that on a Linux desktop, but my search reveals no contender. There are so many filesystems for ...
2
votes
1answer
1k views

How should I set up additional EBS storage on an Amazon EC2 instance?

One of my clients has three EC2 servers on the Amazon cloud, with several attached EBS devices: server 1 and server 2 are ubuntu micro instances, and server 3, the main production box, is a ubuntu ...
4
votes
3answers
790 views

slow media - disk cache tuning?

Is there any way to make the system more consistent when using LUKS? (or slow storage in general) as it is everything is snappy until the write buffer is full, then everything grinds to a halt as the ...
3
votes
3answers
108 views

Share unchanging data from a central repository on a network

I have a bunch of different binary files (total size of all files is circa ~500GB) stored in a hard drive that is mounted to machine001. I have 200 other machines that need to access this data for ...
15
votes
4answers
24k views

linux: How can I view all UUIDs for all available disks on my system?

My /etc/fstab contains this: # / was on /dev/sda1 during installation UUID=77d8da74-a690-481a-86d5-9beab5a8e842 / ext4 errors=remount-ro 0 1 There are several other disks on ...
4
votes
3answers
239 views

RAID 1 in linux

I'd like to setup RAID 1 with two drives in linux. I don't have a hardware RAID controller and don't want to buy one, so what is the best software RAID option for linux? Note: If it makes a ...
22
votes
7answers
4k views

How can I use DD to migrate data from an old drive to a new drive?

I am upgrading the internal SATA hard drive on my laptop from a 40G drive to a 160G drive. I have a Linux/Ubuntu desktop which has a SATA card. I would actually like to do the same thing for a couple ...