EX2300 and EX3400 series switches can be recovered by performing a format install from TFTP server if the switch does not boot successfully. This article describes the procedure.

Note: This procedure will format the switch and all configurations will be lost.

For USB format install steps, refer to KB31265 - [EX] How to format install on EX2300 and EX3400 [juniper.net] .

Note: This procedure will format the switch and all configurations will be lost.

1. Download the image from Juniper's support site . Be sure to download the install media image; the file format is tgz.
2. Copy the required image on the TFTP server to the required directory.
3. Reboot the switch and interrupt the boot sequence:
   
   a. Press any key when you see Main Menu to avoid auto boot
   b. Stop at uboot (^C or space to stop autoboot –depending on the uboot version; for older uboot -> press space)
4. Set the switch-management IP address, netmask and gateway IP
   => setenv ipaddr 172.22.157.103
=> setenv gatewayip 172.22.157.1
=> setenv netmask 255.255.255.0
=> setenv serverip 172.22.157.102
=> save
    

   Ping the server to see if is reachable:

   => ping 172.22.157.102
Using FM1@DTSEC1 device
host 172.22.157.102 is alive
    
5. Reboot the switch and interrupt to navigate to OAM menu. Choose option 5.  [M]ore options and then option 5.  [B]oot prompt , which will take you to the loader:

   a. To reboot the switch from u-boot mode:

   => boot
    
   b. To navigate to OAM menu:
   
   Press control+c / ^C or space to stop autoboot

   Main Menu

   1.  Boot [J]unos volume
   2.  Boot Junos volume in [S]afe mode
   3.  [R]eboot
   4.  [B]oot menu
   5.  [M]ore options

   Options Menu

   1.  Recover [J]unos volume
   2.  Recovery mode - [C]LI
   3.  Check [F]ile system
   4.  Enable [V]erbose boot
   5.  [B]oot prompt
   6.  [M]ain menu

6. Issue the install command with the format option to install the Junos image via TFTP: 

   
   loader> install --format tftp://172.22.157.102/junos-install-media-net-arm-32-15.1X53-D55.5.tgz

7. After TFTP installation is done, log in and verify that the new version of the software is properly installed.

2020-03-28: Added link to KB31265 [juniper.net] in Summary

2018-10-28: Corrected typo; changed 'etenv netmask' to 'setenv netmask' in step 4

• How to format install EX2300s and EX3400s via USB