In this article, we will explore the options if a device is stuck in Boot at the stage of "Started run_jflow service"

After upgrade and reboot, the device is stuck at "Started run_jflow service"

[OK] Listening on Virtual machine log manager socket.
[OK] Started Virtual machine log manager.
	Starting Icmd service...
[OK] Started Icmd service.
	Starting cosm service...
[OK] Started cpsm service.
	Starting Ic-depfe service...
[OK] Started Ic-dopfe service.
	Starting run_jflow service...
[OK] Started Check for failure of daemons and alarm.
[OK] Started run_ jflow service.
[OK] Started /etc/rc. local Compatibility.
[OK] Started Getty on ttyl.
[OK] Reached target Login Prompts.
[OK] Reached target Multi-User System.
[OK] Stopped run_jflow service.
	Starting run_jflow service...
	Starting Update UTMP about System Runlevel Changes...
[OK] Started Update UTMP about System Runlevel Changes.
[OK] Started run_jflow service.				<<<<<-------------------
[nettools@436046: logged in to share session in this device.]
[nettools@436072: logged in to share session in this device.]
[nettools@436108: logged in to share session in this device.]
[nettools@436140: logged in to share session in this device.]
[nettools@436207: logged in to share session in this device.]
[nettools@436216: logged in to share session in this device.]
[nettools@436260: logged in to share session in this device.]

Step-1: Try to power down the device and reboot again. If it doesn't work, then try the manual boot method.

Step-2: Steps to Manual Boot the device

1. Power off the device, such as a router or a switch, by pressing the power button on the front panel.
2. Connect and configure the management device, such as a PC or a laptop, as follows:
   1. Turn off the power to the management device.
   2. Plug one end of the Ethernet rollover cable supplied with the device into the RJ-45–to–DB-9 serial port adapter supplied with the device.
   3. Plug the RJ-45–to–DB-9 serial port adapter into the serial port on the management device.
   4. Connect the other end of the Ethernet rollover cable to the console port on the device.
   5. Turn on the power to the management device.
   6. On the management device, start your asynchronous terminal emulation application (such as Microsoft Windows Hyperterminal) and select the appropriate communication (COM) port to use (for example, COM1).
3. Configure the port settings as follows: (Bits per second: 9600, Data bits: 8, Parity: None, Stop bits: 1, Flow control: None)
4. Power on the device by pressing the power button on the front panel.
5. Verify that the POWER LED on the front panel turns green. And you can see the Junos Main menu appears.

Note:

In releases before Junos OS Release 17.3, the Junos Main Menu appears for 3 seconds on startup before automatically booting the /junos volume. Press any key within the 3-second window to stop the automatic boot sequence and display the Junos Main Menu.

Starting in Junos OS Release 17.3, press Ctrl+c within the 3-second window to stop the automatic boot sequence and display the Junos Main Menu.

Step-3: On the Boot Manager you can choose which Boot Option Menu to boot from. Default Boot option would be EFI HDD Device.

Secure boot is enforced
Press Esc for boot options
ОСС3
Intel (R) Xeon (R) CPU @ 2. 50GHZ						2. 50 GHz
QFXS_SFP_00. 32_02. 01									32768 MB RAM


Continue
Boot Manager								This selection will take you to the Boot Manager
Device Manager
Setup Utility

/-----------------------------------------------------------------------------------Y
|								Boot Manager										|
/-----------------------------------------------------------------------------------Y

Boot Option Menu
EFI HDD Device (SFSA050GM2AK1TO-C-8C-12A-JUN) •
EFI HDD Device 1 (SFSA050GM2AK1TO-C-8C-12A-JUN)
EFI Network 0 for IPv4 (60-C7-8D-2F-49-DE) 
EFI Network 1 for IPv4 (60-C7-8D-2F-49-DF) 
EFI Network 2 for IPv4 (60-C7-8D-2F-49-E0)


^ and v to change option, ENTER to select an option, Esc to exit 

Now booting : EFl HDD Device (STSA050GMZAKTI0-6-86-12A-JUN)
Welcome to GRUB!

Secure Grub2 Diskboot
		GNU GRUB version 2.02 juniper/rel_V4-3-g49e19e8~
		

/-----------------------------------------------------------------------------------Y
*Serial console efi_P
Serial console jspare_P

Step-4: If the first boot option doesn't help in proper booting, use the 2nd boot option. EFI HDD Device.

Step-5: Manually choosing the secondary SSD EFI HDD Device 1, the device should boot up. It might boot up iin Amnesiac mode.

Step-6: At this stage, login using root, first upgrade the device and then load the config on the box.