USB Autoinstallation on SRX Branch Platforms for Software Upgrade or Downgrade

By | December 25, 2013

The SRX Series USB Auto install feature simplifies the upgrading of Junos OS images, when there is no console access to an SRX Series device that is located at a remote site. This feature allows you to upgrade the Junos OS image with the minimum configuration effort by just inserting a USB flash drive into the USB port of the SRX Series device and performing a few simple steps. This feature can also be used to reformat the boot device and recover the SRX Series device after boot media corruption.

Before you begin the installation, ensure that the following prerequisites are met:

The Junos OS upgrade image and autoinstall.conf files must be copied to the USB device. The instructions on how to copy the image and create the file are provided below. Make sure that adequate space is available on the SRX Series device to install the software image.

Preparing the Autoinstall USB key

Any USB key, which is formatted with the FAT/FAT32 file systems, can be used for the autoinstall. USB keys from vendors, such as Sandisk, Transcend, Unigen, Kingston, and Lexer are recommended for this installation:

  • Plug in the USB key to a Windows PC/Laptop.
  • Right-click the Removable Disk drive that is detected in My Computer.
  • Format the drive with the FAT/FAT32 file system.
  • Copy the Junos package to the USB key.Note: Only one Junos package should be present for the autoinstall to proceed. Only packages with the junos-srxsme* name are recognized.
  • Check the drive name that is detected in My Computer for the USB key. Open a command prompt and type echo “” > < drive-name >:\autoinstall.conf. For example, if the detected drive is F:, issue the echo “” > F:\autoinstall.conf command via the command prompt. This will create an autoinstall.conf file on the USB key. This empty file indicates to the system that the USB key is an autoinstall USB key.Note: If ‘Hide extentions for known file types’ is enabled on the system, Windows Explorer creates ‘autoinstall.conf’ with the ‘.txt’ extension. So, the above method is recommended.