Re: How do you boot from usb from => mode?

Hi, Matt

I am assuming you already try the "reset" or "boot" commands and you reached the same prompt; if not please try them.

If the SRX is getting stuck on uboot (not even reaching Loader) you could try the steps mentioned in the following KB in order to upgrade/reinstall the Loader and maybe after that you could try to recover the device with a USB drive from the Loader:

https://kb.juniper.net/InfoCenter/index?page=content&id=KB14175

https://kb.juniper.net/InfoCenter/index?page=content&id=KB30427&cat=SRX_110&actp=LIST

A different person tried this already and it worked:

https://forums.juniper.net/t5/SRX-Services-Gateway/Recovery-issue-help-using-u-boot/td-p/217897

Also you can try, from u-boot, to boot from the secondary partition of your SRX:

https://thorsten-on-tech.blog/2013/11/13/recover-juniper-srx-from-failed-boot/

Ive also see the "setenv bootloader usb1:0" command in a couple of forums, however Im not sure about how to use it, maybe you can research more about it; it seems to work with a usb stick:

https://www.reddit.com/r/Juniper/comments/9cutat/ex3400_stuck_in_uboot_loader/

https://forums.juniper.net/t5/Junos/Juniper-EX3400-stuck-in-boot-loop-after-upgrade/td-p/307064

https://lists.gt.net/nsp/juniper/66012

Also you could try creating a snapshot from a working SRX in to a USB and inserted in the faulty SRX and have it booting from this usb:

https://www.juniper.net/documentation/en_US/junos/topics/example/security-boot-device-srx-series-device-configuring.html#jd0e168

I hope the above info helps you, please let us know.