Description

The issue you observed with the backup Routing Engine (RE) on a PTX10008, which was not responding to CLI commands and displaying the error “the command-handler subsystem is not responding to management requests,” was identified as being caused by a mismatch in Junos OS versions between the master and backup REs. This version mismatch prevented the command-handler process on the backup RE from functioning correctly.

Symptoms

{backup}
[email protected]> request system reboot 
The entire system (all nodes) will reboot causing traffic loss, do you wish to continue? [yes,no] (no) yes

error: the command-handler subsystem is not responding to management requests
error: the command-handler subsystem is not responding to management requests

 

[email protected]> request system software rollback    
error: the command-handler subsystem is not responding to management requests

{backup}
[email protected]> show version 
error: the command-handler subsystem is not responding to management requests

 

labroot@labroot-re1> show version invoke-on all-routing-engines 
re0:
--------------------------------------------------------------------------
Model: ptx10008
Junos: 23.2R1.15-EVO
Yocto: 3.0.2
Linux Kernel: 5.2.60-yocto-standard-g12d8464
JUNOS-EVO OS 64-bit [junos-evo-install-ptx-x86-64-23.2R1.15-EVO]

re1:
--------------------------------------------------------------------------
Model: ptx10008
Junos: 23.4R2-S3.10-EVO
Yocto: 3.0.2
Linux Kernel: 5.2.60-yocto-standard-g85baac8
JUNOS Selective Update J13.1 [junos-evo-install-ptx-x86-64-23.4R2-S3-J13.1-EVO]
JUNOS-EVO OS 64-bit [junos-evo-install-ptx-x86-64-23.4R2-S3.10-EVO]

Solution

On Master RE, the Junos EVO software versions can be synchronized using the below command:

 

  • request system software sync all-versions

The software was synchronized from the master RE to the backup RE, which automatically rebooted to complete the upgrade. Afterward, both REs came up on the same Junos EVO version, and the command-handler subsystem functioned normally. 

Modification History

2025-09-19 : Article Created