Description

This article provides information on how to upload the restricted kernel files to JTAC.

Symptoms

By default, on Junos, kernel core files are generated with restrictive access rights, so that the sensitive information, which is contained within these files, is available only to a restricted set of users.

The following example is of such file access permissions (read/write for root user):

user@router1-re0> show system core-dumps
-rw------- 1 root wheel 278392832 Oct 10 17:25 /var/crash/vmcore.0
/var/tmp/*core*: No such file or directory
/var/tmp/pics/*core*: No such file or directory
-rw-r--r-- 1 root wheel 15273950 Oct 10 17:25 /var/crash/kernel.0
total files: 2
This may cause an issue, when these core files are requested by JTAC and the customer does not have immediate knowledge of the root password.

Solution


Within JunOS, every user, who is set with the maintenance level (root like) privilege, can access the file archive command. This command creates an archive with the current user as the owner; but also allows the root owned files to be archived. This allows the user to then upload the resulting file to an SFTP or FTP server.

  1. First,  confirm if you are with the maintenance level: 
    user@router1-re0> show cli authorization | match maintenance
maintenance -- Can become the super-user
  2. Create an compressed archive of the core file: 
    user@router1-re0> file archive compress source /var/crash/vmcore.0 destination /var/tmp/vmcore.0
/usr/bin/tar: Removing leading `/' from member names
  3. The following command displays the newly created file with the current user's ownership. The new file has a .tgz extension: 
    user@router1-re0> file list detail /var/tmp/vmcore.0.tgz
-rw------- 1 user field 68809080 Jan 7 19:34 /var/tmp/vmcore.0.tgz
total 1
  4. You can then copy the files to a SFTP or FTP server (usually both the vmcore and kernel files are required): 
    user@router1-re0> file copy /var/tmp/vmcore.0.tar scp://[email protected]:/pub/incoming/2012-0107-0000/
The authenticity of host 'sftp.juniper.net (66.129.230.52)' can't be established.
RSA key fingerprint is 8b:6b:36:94:ea:6d:92:55:bb:1f:80:3e:54:ea:4d:30.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'sftp.juniper.net,66.129.230.52' (RSA) to the list of known hosts.
[email protected]'s password:
For more information, refer to KB23337 - How to upload large files to a JTAC Case [juniper.net] .