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[ACX] How to mount a USB drive on ACX5448



Article ID: KB36398 KB Last Updated: 30 Dec 2020Version: 1.0

This article explains how to mount a USB drive on an ACX5448 device and copy files from it. This article also provides the steps to copy files from vmhost to Junos.


The following procedure allows users to mount a USB device on an ACX5448 device.  This can be helpful if network connectivity is unavailable and you need to copy files to or from the device.

Note: It is recommended to have USB with FAT32 format. USB is not detected on ACX5448 in shell/privilege mode. ACX5448 is a platform where Junos runs as vm on wrl. Login to vhclient is needed to capture the USB activity.
  1. Enter the shell as root:

    user@router> start shell user root
    root@router:/var/home/labroot #  vhclient -s
    Last login: day Month date <timestamp> from router on pts/2
  2. Before inserting the USB device, perform the following:

    root@router-node:~# ls /dev/sd*
    /dev/sda   /dev/sda2  /dev/sda4  /dev/sda6  /dev/sdb1  /dev/sdb3  /dev/sdb5  /dev/sdc
    /dev/sda1  /dev/sda3  /dev/sda5  /dev/sdb   /dev/sdb2  /dev/sdb4  /dev/sdb6
  3. Insert the USB drive in the USB port. The following output provides info of USB attach:

    root@router-node:~# dmesg | tail
    [  493.244240] scsi 6:0:0:0: Direct-Access     JetFlash Transcend 16GB   1100 PQ: 0 ANSI: 6
    [  493.244468] sd 6:0:0:0: Attached scsi generic sg2 type 0
    [  493.245149] sd 6:0:0:0: [sdc] 30197760 512-byte logical blocks: (15.5 GB/14.4 GiB)
    [  493.245876] sd 6:0:0:0: [sdc] Write Protect is off
    [  493.245879] sd 6:0:0:0: [sdc] Mode Sense: 43 00 00 00
    [  493.246653] sd 6:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
    [  493.251845]  sdc: sdc1   <<<<<< location
    [  493.254346] sd 6:0:0:0: [sdc] Attached SCSI removable disk   <-- USB
    root@router-node:~# ls /dev/sd*
    /dev/sda   /dev/sda2  /dev/sda4  /dev/sda6  /dev/sdb1  /dev/sdb3  /dev/sdb5  /dev/sdc
    /dev/sda1  /dev/sda3  /dev/sda5  /dev/sdb   /dev/sdb2  /dev/sdb4  /dev/sdb6  /dev/sdc1 
    Note: '/dev/sdc1' is the USB drive. 
  4. Create a directory for the USB drive to mount to:

    root@router-node:~# mkdir /var/tmp/usb
  5. Mount the USB drive to the /var/tmp/usb directory:

    root@router-node::~# mount /dev/sdc1 /var/tmp/usb/
  6. Check the USB files after mounting the USB:

    root@router-node: ls /var/tmp/usb
    System Volume Information  images.tgz   <--- USB files

    Note: 'ls /var/tmp/usb' will show all the files in the USB drive.

  7. Copy any of the USB files to the /var/tmp/usb directory:

    root@router-node: cp /var/tmp/usb/images.tgz /var/tmp
    root@router-node: ls /var/tmp

    The images.tgz file from the USB is successfully copied to the /var/tmp directory.

  8. To move the file from vmhost to Junos, copy the files to /var/log or /var/crash in vhclient:

    root@router-node:~# cp /var/tmp/images.tgz /var/crash/
    root@router-node:~# ls -l /var/crash/images.tgz
    -rw------- 1 root root 2881405 <timestamp> /var/crash/images.tgz
    root@router-node:~# exit
    rlogin: connection closed
    root@router:/var/home/labroot # cli
  9. Now logged into CLI mode, use the following command to copy files from vmhost to Junos:

    user@router> request vmhost file-copy crash from-jnode images.tgz to-vjunos /var/tmp/images.tgz
    user@router> file list /var/tmp/images.tgz
    user@router> file list /var/tmp/images.tgz detail
    -rw-------  1 root  wheel    2881405 <timestamp> /var/tmp/images.tgz
    total files: 1
    File copied successfully to Junos location /var/tmp/
    Reference link: request vmhost copy vjunos-to-jnode  
  10. Unmount the USB drive after the file is completely copied:

    Enter the shell as root:

    user@router> start shell user root
    root@router:/var/home/labroot #  vhclient -s
    Last login: day Month date <timestamp> from router on pts/2
    root@router-node: umount /var/tmp/usb
    Note: ‚ÄčEnsure the USB devices are unmounted properly before removing them from the router. For devices with multiple USBs, be sure to unmount both devices.
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