Home/ Questions/Q 7865185
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-03T00:00:40+00:00

I’ve written following script in linux to get USB detail: this script is executed

  • 0

I’ve written following script in linux to get USB detail: this script is executed from udev when usb is attached.

    fgrep -A 15 'New USB device found' /var/log/messages | tail -n 16 > usb_detail
    SERIAL=$(sed -n '5s/A.*: //p' usb_detail)
    SIZE=$(sed -n '10s/A.*: //p' usb_detail)
    MOUNT=$(sed -n '14s/A.*: //p' usb_detail)
    blkid > Label
    LABEL=$(grep $MOUNT Label | awk '{print $2}')

Now problem is that I’m getting all values (Serial No, Size, Mount on) but when it goes to check lable of usb from BLKID then i get nothing. this command gives me nothing in output:

blkid > Label

this command is working properly in command prompt. but when i run it in this script (which is called from UDEV when usb is attached) then it doesn’t give any output.

So how can i figure out that what is main problem and why I’m not getting anything in LABEL file?

Here is my /var/log/messages:

Apr 28 08:25:58 box2 kernel: usb 1-3: New USB device found, idVendor=0411, idProduct=0105
Apr 28 08:25:58 box2 kernel: usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=5
Apr 28 08:25:58 box2 kernel: usb 1-3: Product: USB-SATA Bridge
Apr 28 08:25:58 box2 kernel: usb 1-3: Manufacturer: BUFFALO
Apr 28 08:25:58 box2 kernel: usb 1-3: SerialNumber: 00001412AA38
Apr 28 08:25:58 box2 kernel: usb 1-3: configuration #1 chosen from 1 choice
Apr 28 08:25:58 box2 kernel: scsi25 : SCSI emulation for USB Mass Storage devices
Apr 28 08:26:05 box2 kernel: scsi 25:0:0:0: Direct-Access     BUFFALO  External HDD          PQ: 0 ANSI: 2 CCS
Apr 28 08:26:05 box2 kernel: sd 25:0:0:0: Attached scsi generic sg0 type 0
Apr 28 08:26:05 box2 kernel: sd 25:0:0:0: [sda] 976773168 512-byte logical blocks: (500 GB/465 GiB)
Apr 28 08:26:05 box2 kernel: sd 25:0:0:0: [sda] Write Protect is off
Apr 28 08:26:05 box2 kernel: sd 25:0:0:0: [sda] Assuming drive cache: write through
Apr 28 08:26:05 box2 kernel: sd 25:0:0:0: [sda] Assuming drive cache: write through
Apr 28 08:26:05 box2 kernel: sda: sda1
Apr 28 08:26:05 box2 kernel: sd 25:0:0:0: [sda] Assuming drive cache: write through
Apr 28 08:26:05 box2 kernel: sd 25:0:0:0: [sda] Attached SCSI disk

and here is blkid output from command prompt:

[root@box2 usbmon]# blkid
/dev/sdf1: UUID="2d1bd58e-86ea-4ab2-99e3-ec2d1fb24021" TYPE="ext4" 
/dev/sdf2: UUID="Je95wE-NW7f-Mqlv-UBgi-qNOL-8i35-8cUUTj" TYPE="LVM2_member" 
/dev/mapper/vg_box2-lv_root: UUID="27cf24f7-4e7d-42bd-97be-09ddc6eb614b" TYPE="ext4" 
/dev/mapper/vg_box2-lv_swap: UUID="36c54ea3-f9f3-455a-9c84-58e7317d1e60" TYPE="swap" 
/dev/mapper/vg_box2-lv_home: UUID="5cac0192-2757-4cf6-b70f-d9ff8fbe6f36" TYPE="ext4" 
/dev/sda1: LABEL="BU5" UUID="242DB177461FD69A" TYPE="ntfs"
Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    i fixed the issue by changing syntax

    blkid > Label

    to

    /sbin/blkid > Label

    dont know why but sometimes it works.

    • 0