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Issue with Core Dump Personalization in AIX

  • 1.  Issue with Core Dump Personalization in AIX

    Posted Fri May 19, 2023 04:42 PM

    Hello community,

    We are facing an issue regarding the personalization of core dump files generation as documented in this IBM URL

    The problem is that the core dumps are not being generated when the personalization parameters are enabled for non-privileged accounts, the core dumps are only generated when logging in as root through SSH.

    It's important to mention that when logging in as root through SSH and then switch (su) to a non-privileged account the core dump files are generated as expected.

    The server and the account are configured as following:

     # lsattr -E -l sys0 | grep full

    fullcore Enable full CORE dump

    # lsuser -f -a fsize core core_hard ACCOUNT





    # lscore ACCOUNT

    compression: on

    path specification: on

    corefile location: /users/ACCOUNT/dir_coredumps

    naming specification: on

    We force the core dump generation (Segmentation Fault) executing the following C code :

    #include <stdio.h>

    int main() {

        int *ptr = NULL;

        *ptr = 5;

        return 0;


    After some research our hypothesis is that the issue could be related to the SSH protocol, because, when we access the server directly from the HMC or using the TELNET protocol, the generation of core dump files is successful for both, root and non-privileged accounts.

    The test was executed in the following environment:

    SO version: AIX 7200-05-05-2246

    OpenSSH version:

    $ lslpp -L | grep -i ssh

      openssh.base.client    C     F    Open Secure Shell Commands

      openssh.base.server    C     F    Open Secure Shell Server

    $ ssh -V

    OpenSSH_8.1p1, OpenSSL 1.1.1l  24 Aug 2021

    ¿Do you have any ideas to solve this issue?, we really appreciate any suggestions.



    Aarón Gaona

  • 2.  RE: Issue with Core Dump Personalization in AIX

    Posted Mon May 22, 2023 04:36 AM

    I would run the lsuser command after switching to the non-root user as the user may have had various login scripts run like .profile etc.

    Then check the difference between env for root and no-root and look for different settings.
    If that does not help raise an AIX PMR (now called a support case) - assuming you paid for AIX Support.


    Nigel Griffiths

  • 3.  RE: Issue with Core Dump Personalization in AIX

    Posted Tue May 30, 2023 06:06 PM

    Hi Nigel,

    We already post our case with IBM/AIX support, unfortunately they didn't give us any solution to this issue, their answer was that this was not an issue with the IBM provided openssh and Openssh is working as designed. At the end, they only recommend us to submit a request for enhancement (RFE). 

    Thanks for your time,


    Aarón Ernesto Gaona Amezcua