Ethernet Switching
Ethernet Switching

Unable to boot into single-user mode on EX2200

‎01-24-2020 09:38 AM

I have bought two second hand EX2200 units, one was factory reset the other does not seem so.

The instructions at the below URL state to boot into single-user mode and perform the recovery from there. The problem is that the switch does not pause for a few seconds for me to press the space bar key to get to the prompt to enter boot -s command.

 

https://www.juniper.net/documentation/en_US/junos/topics/task/configuration/authentication-root-pass...

 

This is what I am seeing at start up. The moment I see Hit [Enter] to boot immediately, or space bar for command prompt, it shows a countdown from 1 but it goes away faster than a second and no matter how fast I press on my space bar I cannot get it to stop and give me a prompt to enter single-user mode.

 

U-Boot 1.1.6 (Jul 26 2011 - 03:19:50)

Board: EX2200-24T-4G 4.18
EPLD:  Version 04.100311 (0x10)
DRAM:  Initializing (512MB)
Flash: 8 MB

Firmware Version:01.00.00
USB:   scanning bus for devices... 3 USB Device(s) found
       scanning bus for storage devices... 1 Storage Device(s) found

ELF file is 32 bit
Consoles: U-Boot console

FreeBSD/arm U-Boot loader, Revision 1.1
(builder@dagmath.juniper.net, Tue Jul 26 01:25:53 UTC 2011)
Memory: 512MB
bootsequencing is enabled
bootsuccess is set
new boot device = disk0s1:
Loading /boot/defaults/loader.conf
/kernel data=0x889590+0xdd8ac syms=[0x4+0xf0f80+0x4+0xc89d0]


Hit [Enter] to boot immediately, or space bar for command prompt.
Booting [/kernel]...
Kernel entry at 0x1400100 ...
GDB: debug ports: uart
GDB: current port: uart
KDB: debugger backends: ddb gdb
KDB: current backend: ddb
Copyright (c) 1996-2016, Juniper Networks, Inc.
All rights reserved.
Copyright (c) 1992-2006 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
JUNOS 12.3R12.4 #0: 2016-01-20 04:27:03 UTC
7 REPLIES 7
Highlighted
Ethernet Switching
Solution
Accepted by topic author silviubv@gmail.com
‎01-29-2020 04:20 AM

Re: Unable to boot into single-user mode on EX2200

‎01-24-2020 12:40 PM

Hi silviubv@gmail.com,

 

I faced something similar once,  as soon as you pull the power cord and put it back you might want to start hitting the space relentlessly until you get to the loader prompt after getting to the loader prompt I would recommend you to re-write the entire file system so you will have a healthy switch and fix any underlying issues. here is the procedure: https://kb.juniper.net/InfoCenter/index?page=content&id=KB20643

 

Regards,
Lil Dexx JNCIE-ENT#863

 

If this solves your problem, please mark this post as "Accepted Solution" so we can help others too Smiley Happy

 

Highlighted
Ethernet Switching

Re: Unable to boot into single-user mode on EX2200

‎01-24-2020 01:41 PM

Hi LilDexx,

 

I have tried to clobber the space bar relentlessly, no go.

Do you know if the unit supports some sort of factory reset from the front pannel button ?  My EX2200 model does not have a LCD screen, just 1 button with.

Highlighted
Ethernet Switching

Re: Unable to boot into single-user mode on EX2200

‎01-24-2020 02:15 PM

Hey silviubv,

 

Unfortunatey not since there is no LCD panel as you mentioned, nevertheless,  there is a little button on the front to the right of the SFP ports do the following:

 

- 1 Hold it down for 30 seconds,
- 2 Quickly let go,
- 3 Rinse and repeat step 1 and 2 until all ports light up, this might allow you to login with root and no password, please let me know how it goes.

 

Regards,
Lil Dexx JNCIE-ENT#863

 

If this solves your problem, please mark this post as "Accepted Solution" so we can help others too Smiley Happy

Highlighted
Ethernet Switching

Re: Unable to boot into single-user mode on EX2200

‎01-25-2020 08:09 AM

Hi Lil Dexx,

 

I've tried to do your recommended method to hold the button down for 30 seconds and then repeat. I was not able to get all the lights to turn on, or to be able to login as root without a password.

I've also gave a few more shots to press the spacebar to get to the prompt, I can see the timer counting down from 1 and in that 1 second I am clearly pressing the space bar but it's not getting registered.

I am at a loss with this unit. Not sure what to do next. If I open up the unit up, is there anything phisical that I can fiddle with to get it to reset ?

Highlighted
Ethernet Switching

Re: Unable to boot into single-user mode on EX2200

‎01-25-2020 08:32 AM

You do know that depending upon the age of this switch, you might be able to get an RMA replacement, without a service contract needed.  You would need to provide TAC with the SN of the switch.

Highlighted
Ethernet Switching

Re: Unable to boot into single-user mode on EX2200

[ Edited ]
‎01-27-2020 08:19 AM

If you are refused an RMA by JTAC there's usually only one route left which is a reformat

 

https://kb.juniper.net/InfoCenter/index?page=content&id=KB27255

https://kb.juniper.net/InfoCenter/index?page=content&id=KB20643

 

Be aware this is a LAST RESORT as you are breaking this into UBOOT and then it rewrites everything. Any root cause analysis is not possible after this as everything is gone post install.

KR

Adam

~~~~~~~~~~~~~~~~~~~~~~~
- Please Kudos if you found my response helpful
- Please accept my response as a 'Accepted Solution' if it solved your query
Highlighted
Ethernet Switching

Re: Unable to boot into single-user mode on EX2200

‎01-28-2020 04:52 PM

Hello everyone,

The solution to my problem (not being able to enter single user mode by pressing the space bar) was due to the terminal emulator minicom that was incorrectly set. After much tinkering I switched to a Windows laptop and open a serial connection using Putty and all worked fine, I was able to enter single-user mode. So I went back to my linux laptop and double check the settings; after setting Hardware Flow Control to No I was able to press the spacebar key and enter singe-user mode via minicom also.

After resetting the root password the switch was booting from image 2, so I went ahead and performed the install --format to restore the switch.

The switch works fine now.

 

Screenshot_2020-01-28_05-05-32.png