In certain scenarios like Sudden Power outages, Software upgrades etc. QFX device may boot up into amnesiac mode but with partial configuration committed.
Switch may display the hostname however may not provide enough privilege to execute CLI commands.
This KB enlists the steps that can help recover the switch in the state described above.
In certain scenarios like Sudden Power outage, Software upgrade etc QFX device may boot up into amnesiac mode but with partial configuration committed.
Switch may display the hostname however may not provide enough privilege to execute all CLI commands.
This KB enlists the steps which can help in recovering the switch in the state described above.

The device will be booted into amnesiac mode which means it will be accessible only by entering username and with no password.
Sometimes a locally configured username may get accepted and sometimes only the "root" username might be accepted with no password required.
 
Post login into the device minimal CLI options are available and the device cannot be rebooted Via CLI

device> ?
Possible completions:
file   Perform file operations
help Provide help information
op  Invoke an operation script
quit Exit the management session
request Make system-level requests
set Set CLI properties, date/time, craft interface message
start Start shell
test Perform diagnostic debugging

As we can see above there is no option to run the show command and no possibility of rebooting via CLI.

device> request ?
Possible completions:
access-security Request access security feature
ancp Request ANCP operation
auto-configuration Request auto-configuration action
chassis Perform chassis-specific operations
dhcp Perform DHCP operations
dhcpv6 Perform DHCPv6 operations
interface Perform interface operations
ipsec Perform IP Security operations
jdaf Request JDAF operation
lacp Request LACP actions
protection-group Request protection group related operations
services Request service options

This issue happens when the device is not booted correctly or there might be a file system corruption or issue with the configuration file leading to a partial commit being performed by MGD daemon during Bootup.
 
Below are steps that can help in recovering from this state:-
 
Step 1:-  The very first step is to Power cycle the device so that the Switch is allowed to go through a complete boot cycle. Once Switch comes up verify if the issue is resolved and follow the next step if the issue still exists.
 
Step2:-  If the above does not help please try Linux recovery using the below KB during which it is recommended to choose yes for the below options:-

KB:- https://supportportal.juniper.net/s/article/EX-QFX-Recovery-installation-for-QFX10K-and-EX4300-MP

Enter y to format the junos data disk
 
Do you want to format Junos data disk?[y/n]
 
Enter y to format the junos config >>>>>>>>>>>>>>>>>>>>>> enter y
 
 
 
Do you want to format Junos config disk?[y/n]
 
Enter y to reimage linux host >>>>>>>>>>>>>>>>>>>>>> enter y
 
 
 
Do you want to reimage linux host?[y/n] y
 
Enter 1 to proceed with the recovery >>>>>>>>>>>>>>>>>>>>>> enter y

Please note that the above will clean the configuration from the device and you may need to reconfigure it so please Ensure to keep the configuration backup for reconfiguration.
 
Step3:-
If in case you still face the issue then the Last option will be to format install the device using the below KB:-

https://supportportal.juniper.net/s/article/QFX10K-Procedure-to-format-install-QFX10002-72Q-device-using-a-USB

NOTE:-The above will require a USB
 
 
If the issue is still seen then please open a case with JTAC.