Is there any C function that will translate UUIDs into device names? I have a little graphical mount tool that can read user-mountable device names from /etc/fstab and lets you cycle through the list and mount or unmount them. But it doesn't work with UUIDs, which are preferred these days. Is there any way around this?
View 2 RepliesI am very much new to Linux programming. My question is Is there any way to read UUID of a device or partition in linux programatically. Is there any c/c++ API for user-space applications. I found some commands "sudo vol_id --uuid /dev/sda1", "sudo blkid", "ls -l /dev/disk/by-uuid/". But all are commands which we need to run in terminal. But I need to achieve this from a c/c++ program. (FYI: I need to read uuid of root filesystem ("/") where Linux has been installed.)
View 1 Replies View RelatedI am very much new to Linux programming. My question is Is there any way to read UUID of a device or partition in linux programatically. Is there any c/c++ API for user-space applications. I found some commands "sudo vol_id --uuid /dev/sda1", "sudo blkid", "ls -l /dev/disk/by-uuid/". But all are commands which we need to run in terminal. But i need to achieve this from a c/c++ program. Can some one help me in this problem.(FYI: I need to read uuid of root filesystem ("/") where Linux has been installed.)
View 9 Replies View RelatedI have an SiI hardware SATA RAID card, with two 500GB disks in mirrored RAID configuration. When I first plugged them in and set it up, things seemed to work ok, but on boot the raid controller told me that the RAID needed rebuilding, and it would happen automatically after POST. So I didn't worry about it, and the drive mounted fine, and it's been that way for years. I just went in and manually on-line rebuilt the RAID in the controller's BIOS, and now when I boot into Ubuntu, both disks show up in fdisk, but neither show up in /dev/disk/by-uuid. Am I missing something?
View 9 Replies View RelatedI need a command to display the next info from my hdd:
device name - filesystem - uuid - mount point
I found blkid but the mount point is not displayed, I've already look in man but there is no parameter for that
Fresh install of 9.10. Update all. The update froze at the very end: configuring grub-pc. I let it run like that all night before settling for a reboot while the update manager was still running. (The update also raised the kernel version.) After reboot, I tried the newer kernel [2.6.31-17-generic] at the grub menu and got this error:
Quote:
udevadm trigger is not permitted while udev is unconfigured.
udevadm settle is not permitted while udev is unconfigured.
svgalib: Cannot open /dev/mem.[code].....
And, cat /proc/modules gives me a long list of modules (too much to retype for now).So my hard drive is there. maybe some errors on the / home partition [sda6] and I can get to the root directory.
FYI: MS-win XP still boots fine from grub.
UUIDs make fstab hard to read, so.. Is it possible to use udev rules to prevent HDs to change device, instead of using UUID in /etc/fstab?
View 2 Replies View RelatedI just attempted to install to a USB drive, and somehow in the process, GRUB overwrote my Windows 7 bootloader on the internal disk. My work laptop is now booting into a grub recovery whenever my USB key isn't present (with error: no such device and the uuid) - and hangs on a blinking cursor whenever the key is plugged in.I'm not familiar with what my options are for grub rescue, but ls shows (hd0) (hd0,msdos2) (hd0,msdos1) (fd0)
My laptop is encrypted, so I don't have much chance of recovery unless I can get back to the windows bootloader.
I seem to have another issue with my raid system
mount -a
mount: special device UUID=fb518c74:2b6bd0f4:66db5ce6:7e004239 does not exist
but when i do mdadm -vv --detail /dev/md5 ... this is what i get --->
/dev/md5:
Version : 1.1
Creation Time : Fri Feb 25 14:07:36 2011
Raid Level : raid1
[code]....
CentOS 5.3 has been running fairly good except for a slow ethernet connection so I thought I would upgrade to CentOS 5.4 to see if that improved things. I had previously changed fstab and menu.lst to use UUID instead of LABEL in order to insulate myself from partition label changes I wanted to make. This worked fine in CentOS 5.3. When I attempted to upgrade from 5.3 to 5.4 using the installation disk and telling it to upgrade rather than do a new install, the installation correctly found my root partition as /dev/sdb8. When I proceeded with the upgrade I received the error:
"Error mounting device UUID=cee298a0-9c47-4a3a-ac84-23db4d20edd5 as /. No such file or directory. This most likely means the partition has not been formatted."
But of course it has been formatted and is my / partition running CentOS 5.3 as I type. how to fix this to get CentOS 5.3 upgraded ? Di I have to use LABEL in fstab and menu.lst for my partitions,or perhaps just for my root partition ? Any other ideas why this is failing ?
I'm running Kubuntu Karmic on my Dell Inspiron laptop - about 200 bug fixes behind because my only available internet is a cellular connection on a crappy wi-fi router - and last night, I suspended it, but it shut down instead. Not a problem, it does this fairly often, figure the RAM gets jostled or something.
But when I go to boot it up, it gets stuck at the pre-loading screen before getting garbled and dropping to the shell, where it says "mount: mounting /dev/disk/by-uuid/[insert hex code here] failed: invalid argument". Of course, mounting /root/sys, /root/dev and /root/proc fails, (directory does not exist) and it gives me the busybox initramfs prompt.
Basically, today I installed Ubuntu on my Toshiba NB200 to dual boot with XP. The installation went okay (I think) but after, when I rebooted, and selected Ubuntu from the possible selections, I got this message:Quote:Gave up waiting for root device.Common problems:
-Boot args (cat /proc/cmdline)
-check rootdelay= (did the system wait long enough?)
-check root= (did the system wait for the right device?)
[code]...
I am new to linux scripting, but I have programming experience. I need to save the UUID for /dev/sda1 as a variable, lets call it id. I am sure there is a way to do this with the awk and blkid commands, but I do not know any of this well enough yet to figure it out and after a couple of hours of reading I am still lost as to exactly how I would put this together. I need to save the uuid as a variable so that I can run an if statement with it
if [ -f /media/$id/file ]
then
echo "copy successful"
else
echo "oh crap!"
honestly all I need the uuid for but I cant check this by doing the same if with /dev/sda1/file so I need to be able to save the uuid into a variable
So I've a computer with a lot of disks which is running Ubuntu 9.04. The setup is made od a software raid 1 array of 200 MB for use in /boot (md0), then another raid1 array of the remaining space as a unique PV for the LVM2 vg0. This vg0 is split in many lv, for /, /usr .... and swap. A few days back, one of the raid1 disk went wrong. So as the raid is built on 160Gb disks and nobody in my town sells so little disks I bought a couple of 320GB disks. The partitioning was made like the original partitions, except that the second partition is way bigger than it was. I replaced the failed disk in the arrays, and now I've an md0 of 200 MB and an md1 of roughly 150GB as it was previously and all is in sync. This replacement was made using a rescue disk (in order to be sure that the machine was not locking anything...)
So I thought it was fine. But upon reboot on the hard disks, I get a fast GRUB message "error: no such device : <UUID ending in 4ec05>. when I start the first Ubuntu entry I get the same error. So I edit the boot entry, remove the "search --no-floppy --fs-uuid --set <UUID ending in 4ec05> " and boot the damn thing. When booted I ran :
[Code]...
I try to get uuid value from variable block got from menu.lst.This try does not work. What is wrong?
Code:
uuid=$( echo $block | awk --re-interval '/(root=UUID=/{ x=gensub(/([0-9a-f-]{36,36})/,"\1","g");
print $1}')
I am having problem with the root disk / fill up. So now that i have the disk information provided from SAN team Id 0:3, how would i do to add this device to / to increase space on Redhat Enterprise server 4?
View 1 Replies View RelatedAfter installing the RT kernel, and updating my boot loader, I get this message. Code: ALERT! /dev/disk/by-uuid/... does not exist. Dropping to a shell! It doesn't make a difference whether I pass the 'root=/dev/', or 'root=UUID=', options to the kernel. I've also noticed a message while the system was attempting to boot up. Code: host side 80-wire cable detection failed, limiting max speed to UDMA33 This is all strange to me as I was running the Debian 2.6.32-5-686 kernel, without any problems.
View 1 Replies View RelatedWhat would be the best way list disk and partitions in the fstab file?
View 1 Replies View RelatedI did searched you tube but my results were not great.I have 2 books on KernelProgramming.I feel I need if some where I can get a video tutorial which can help me to understand how to develop a Linux Device driver that will be great.I had a look at Greg Kroah Hartmans video lecture of developing patches on ......I have been reading books and a lot of stuff.So I wish if I could get a video lecture that would be better
View 1 Replies View RelatedI have a 4 * 1.5TB RAID5 disk array (software linux RAID, formatted with jfs) on my Fedora 12 system and want to expand it by adding another 1.5TB disk. I have added a drive to the system and conducted a simple performance check on it to make sure it was functioning properly:
Code:
# dd if=/tmp/bigfile.dat of=/dev/sdg1
5478774+1 records in
5478774+1 records out
2805132609 bytes (2.8 GB) copied, 168.77 s, 16.6 MB/s
But 16.6 MB/s is lousy. I ran an iostat -dmx 2 on this drive at the time of this lousy performance, and typical output was:
Code:
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
sdb 1.50 0.00 258.50 0.00 16.25 0.00 128.74 0.17 0.66 0.36 9.30
sdg 0.00 3556.00 4160.00 32.00 16.25 16.00 15.76 135.73 35.11 0.24 100.05
(note that sda and sdb are a linux raid mirror set for the / filesystem that holds /tmp). I formatted the new drive (/dev/sdg1) with jfs and mounted it under /mnt2:
Code:
# jfs_mkfs /dev/sdg1
jfs_mkfs version 1.1.13, 17-Jul-2008
Warning! All data on device /dev/sdg1 will be lost!
Continue? (Y/N) y
[code].....
I would like to know what the performance will be like before I add the disk to the array because I don't want to wait for the whole array to be rebuilt before finding out my array is performing badly. The array is used as part of a mythtv system and has up to 6 simultaneous recordings running on it, so it needs to perform well.
I have a Corsair R60 ssd disk which is a disk with both sata and usb connectors. But the usb thing seems to be a bit non-standard, or maybe its just my fedora linux.When I insert the disk using a usb cabel to a running Fedora 14 linux system, a device called /dev/sg3 is added but that is all. No new /dev/sd* device is created so I can't mount the disk.
If I look at
cat /proc/scsi/sg/device_strs
I get
ATA Hitachi HTS54321 FB2O
HL-DT-ST DVDRAM GSA-T50N RP05
Seagate Desktop 0130
Corsair CSSD-R60GB2
So the disk is there. (The last entry) but my linux will for some reason not see it as a usb hard disk. When I insert other usb disks they work fine. It is only this specific disk which causes problems. I have tried on 3 different computers with the same result.
A hint to the problem may be that if I add the disk to a windows system(With usb) the disk is called "A fixed disk" and not a portable disk as expected. The disk works fine with linux If i connect it with the sata cabel, but I would really like to have it working with usb too. (To mount it on computers without sata).
Added:I did try to mount /dev/sg3 but mount say that its not a block device. (File say Its a character special device).
Added output from dmesg:
[ 97.454073] usb 7-1: USB disconnect, address 2
[ 105.913055] hub 2-0:1.0: unable to enumerate USB device on port 3
[ 107.048054] usb 2-3: new high speed USB device using ehci_hcd and address 5
[ 107.162900] usb 2-3: New USB device found, idVendor=1b1c, idProduct=1ab8
[code]....
I found an other guy with exactly the same problem [URL] so I think its beginning to look like a bug in the drives firmware or in the linux kernel.
Final update:Corsair have said that the disk design is broken and there does not seem to be any way to make it work.
2 days ago i have tried to install fedora 11 ...but after i did achieved installation successfully ...and rebooted system ,the device hasn't booted from hard disk ,alternatively it has booted from the network (Broadcom)- the third booting choice in bios - . i have tried three different DVDs ....but no thing changes ...!
View 1 Replies View RelatedI just did a clean install of 11.04. Now when I try to boot the machine I get the following error: Quote:
error: no such device
error: no such disk
error: you need to load the kernel first
Then I am taken to the Grub menu. Selecting anything from the Grub menu brings this error back up. So now I'm stuck with a computer that won't work.?
Sometimes when I restart, my NTFS drives will mount in incorrect directories. It seems to only happen when I plug in USB devices such as flash drives, and keep them in when I boot. I have the fstab file configured correctly, but it still resorts to some odd default mounting points. Edit suposedly the device name changes whenever I boot with a flash drive plugged in. Is there anyway to mount a disk to a dir without pointing to its changing device name.
View 3 Replies View RelatedI have installed 1tb hard drive and would like to partition as follows:
1) / - 20g
2) /swap - 6G
3) /photos /150g
4) /videos /500g
5) /audio /300g
After 2-3 partition an extended partition automatically created in which I am not able to create specified capacity i.e., say I want 150g of /photos partition, the /videos partition is automatically reduced and a free space at the end appears. Some free space is always there which i am not able to understand. Nevertheless i clicked to create, but I get an error viz. 'device not created'.
I've mounted Ubuntu 10.04 ISO using Daemon Tools and Virtual CloneDrive, but I end with thisI've disabled my DVD drive in device manager, but I still get it no matter how many times I try.
View 2 Replies View RelatedI am developing for a Linux based device for which the HOT PLUG option is deactivated. As part of optimizing the code, we also don't want to create device files for unused devices. We understand that both USB attached and fixec SCSI hard disks would create device files like /dev/sda,/dev/sda1 /dev/sdb, /dev/sdb1 etc. Is this understanding correct?
In the case of USB attached SCSI devices, would driver create this device file entry? How is it created? Can somebody please tell me how it is being created automatically. In case I attach a fixed SCSI hard disk before boot up(and create device file /dev/sda1), would USB SCSI device driver create device files starting from /dev/sdb, automatically.
For backup purposes, I built a RAID6 array on USB. When during the night the backup filesystem is being mounted, every so many days, a random disk fails:
Code: sd 9:0:0:0: [sdb] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
sd 9:0:0:0: [sdb] Sense Key : Illegal Request [current]
sd 9:0:0:0: [sdb] Add. Sense: Invalid field in cdb[code].....
In other words, my RAID set fails every so many mounts, but I know how to fix it.What I want to find out is:
- Why is a random drive failed every now and then?
- How can I prevent that drive from being failed?
BTW: I have a second RAID set that has been functioning for years without error, so the setup I use must be correct. The only difference between both RAID arrays is the different vendor of the disks.
I have installed vmware in windows server 2003 enterprise edition. When I installed I changed the default installation folder from c: drive to i: drive, as I do not have space in c: drive. After I captured red hat linux cd in vmware and reached partitioning section and continued I got a message like "an error has occured no valid devices were find on which to create new file systems, please check the hardware for the cause of the problem". The machine is IBM server....
View 1 Replies View RelatedI'm kind of new to programming in Linux & c/c++. I'm currently writing a FileManager using Ubuntu Linux(10.10) for Learning Purposes. I've got started on this project by creating a loopback device to be used as my virtual hard disk. After creating the loop back hard disk and mounting it has the following configuration.
Code: $> sudo fdisk -l /dev/loop0
Disk /dev/loop0: 10 MB, 10977280 bytes
255 heads, 63 sectors/track, 1 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/loop0 doesn't contain a valid partition table Now what I want to do is develop a c++ program to read & write files to this loop back device,which I'm using to simulate an actual hard disk,at the blocks & sectors level. So far I've come up with the following code. But I'm still unable to read files from the hard disk one block at a time.
Code: #include <iostream>
#include <stdio.h>
using namespace std;
int main() {
char block[512]; int length=0;
cout<<"Implementation of the File Handler Read Method..."<<endl;
FILE *f = fopen("/dev/loop0", "r");
if(f == NULL) {
cout<<"Error In Opening the HardDisk File Retuning Error..."<<endl; return -1; }
//Read One Block of Data to Buffer length = fread(block, 1, sizeof(block), f);
/* Do something with the data */ cout<<"Length : "<<length<<endl;
return 0; }
When I run this Program All what I get is the message for NULL. "Error In Opening the HardDisk File Retuning Error...". So I could open the loopback device as a file an access it at the sectors & block level.