This article provides information on how to free up space on dual root partitions to allow upgrading of JUNOS software.

Unable to upgrade SRX, with dual root partitions, due to lack of available flash space. 

First, you have to determine how much storage capacity is on your file system. For more information, refer to KB17367 - How to Determine if SRX Device is Running Out of Storage Space for JUNOS Upgrades [juniper.net] .

You can issue a system cleanup, which will clear up some space, by using the request system storage cleanup command. 

For example:

root@test> request system storage cleanup                         

List of files to delete:

         Size Date         Name
    11B Apr 29 21:37 /cf/var/jail/tmp/alarmd.ts
   421B May 10 12:03 /cf/var/jail/tmp/jweb-users.xml
 153.1K May 10 12:03 /cf/var/jail/tmp/sess_5f85f00e46da7f46612193954cb90b372f8772e3
  16.7K May 13 10:33 /cf/var/log/AV-Messages.0.gz
  71.2K May 13 09:51 /cf/var/log/apppxy.0.gz
  70.5K May 13 09:02 /cf/var/log/apppxy.1.gz
  56.9K May 11 06:41 /cf/var/log/dcd.0.gz
  56.9K May 10 07:44 /cf/var/log/dcd.1.gz
Delete these files ? [yes,no] (no) yes 

root@test> 

After the cleanup, if there is still not enough space for the upgrade, perform the following procedure:

1. Start  the shell by using start shell command on the CLI.

• Issue the following command on the shell:

  find -x /cf/var -type f -exec du -k {} \; | sort –n

• Delete the files at the end of the above generated output.  Here is an example:

      18256   /cf/var/lost+found/#11136/flowd_octeon.core.1.gz
      19600   /cf/var/lost+found/#11136/flowd_octeon.core.0.gz
  

  The first column displays the file size in kilobytes and the second column displays the file location.

• You can also find files, which are greater in than the specific value. For example, the following command will show files whose size will be more than 10MB:

        sh -c 'find / -size +10485760c 2> /dev/null' | xargs du -h | sort -nr

Note : If the command fail, change the directory on command from /cf/var to /var if still fails on shell type 'sh' and then run the command. 
Note :  For freeing up space on a SRX device without dual root partitions, refer to Step 6 of the Software Installation Preparation section present in KB16652 - SRX Getting Started - Junos Software Installation [juniper.net] .

20 mar 2026 added : Note : If the command fail, change the directory on command from /cf/var to /var if still fails on shell type 'sh' and then run the command.