Still unable to generate core dump file.

[root@testans401 ~]# sudo /usr/bin/maxscale -d -lstdout -U maxscale &
[1] 83549
[root@testans401 ~]# 2023-04-25 21:28:01 notice : MaxScale will be run in the terminal process.
2023-04-25 21:28:01 notice : /etc/maxscale.cnf.d does not exist, not reading.
2023-04-25 21:28:01 warning: The 'log_debug' option has no effect in release mode.
2023-04-25 21:28:01 notice : The logging of debug messages has been enabled.
2023-04-25 21:28:01 notice : The logging of info messages has been enabled.
2023-04-25 21:28:01 notice : The logging of notice messages has been enabled.
2023-04-25 21:28:01 notice : The logging of warning messages has been enabled.
2023-04-25 21:28:01 notice : Using up to 2.32GiB of memory for query classifier cache
2023-04-25 21:28:01 notice : syslog logging is disabled.
2023-04-25 21:28:01 notice : maxlog logging is enabled.
2023-04-25 21:28:01 notice : Host: 'testans401.corp.copart.com' OS: Linux@3.10.0-1160.71.1.el7.x86_64, #1 SMP Tue Jun 28 15:37:28 UTC 2022, x86_64 with 4 processor cores (4.00 available).
2023-04-25 21:28:01 notice : Total main memory: 15.49GiB (15.49GiB usable).
2023-04-25 21:28:01 notice : MariaDB MaxScale 23.02.1 started (Commit: 5de96ecc39da80a992fc8f362d22a030a844bef5)
2023-04-25 21:28:01 notice : MaxScale is running in process 83550

Configuration file : /etc/maxscale.cnf
Log directory : /var/log/maxscale
Data directory : /var/lib/maxscale
Module directory : /usr/lib64/maxscale
Service cache : /var/cache/maxscale

2023-04-25 21:28:01 notice : Configuration file: /etc/maxscale.cnf
2023-04-25 21:28:01 notice : Log directory: /var/log/maxscale
2023-04-25 21:28:01 notice : Data directory: /var/lib/maxscale
2023-04-25 21:28:01 notice : Module directory: /usr/lib64/maxscale
2023-04-25 21:28:01 notice : Service cache: /var/cache/maxscale
2023-04-25 21:28:01 notice : Module 'qc_sqlite' loaded from '/usr/lib64/maxscale/libqc_sqlite.so'.
2023-04-25 21:28:01 info : qc_sqlite loaded.
2023-04-25 21:28:01 notice : Query classification results are cached and reused. Memory used per thread: 595MiB
2023-04-25 21:28:01 notice : Password encryption key file '/var/lib/maxscale/.secrets' not found, using configured passwords as plaintext.
2023-04-25 21:28:01 info : [qc_sqlite] In-memory sqlite database successfully opened for thread 140610602904704.
2023-04-25 21:28:01 info : No 'auto_tune' parameters specified, no auto tuning will be performed.
2023-04-25 21:28:01 notice : Using HS256 for JWT signatures
2023-04-25 21:28:01 notice : Started REST API on [testans401]:8080
2023-04-25 21:28:01 notice : No services defined in any of the configuration files
2023-04-25 21:28:01 info : [qc_sqlite] In-memory sqlite database successfully opened for thread 140610431850240.
2023-04-25 21:28:01 info : Epoll instance for listening sockets added to worker epoll instance.
2023-04-25 21:28:01 info : [qc_sqlite] In-memory sqlite database successfully opened for thread 140610423457536.
2023-04-25 21:28:01 info : Epoll instance for listening sockets added to worker epoll instance.
2023-04-25 21:28:01 info : [qc_sqlite] In-memory sqlite database successfully opened for thread 140610415064832.
2023-04-25 21:28:01 info : Epoll instance for listening sockets added to worker epoll instance.
2023-04-25 21:28:01 info : [qc_sqlite] In-memory sqlite database successfully opened for thread 140610406672128.
2023-04-25 21:28:01 info : Epoll instance for listening sockets added to worker epoll instance.
2023-04-25 21:28:01 notice : MaxScale started with 4 worker threads.
2023-04-25 21:28:09 notice : Message from PAM api when authenticating 'nachandra': 'Your password will expire in 11 days.
'
2023-04-25 21:28:09 error : Unknown PAM message type '5'.
2023-04-25 21:28:09 info : Accept authentication from 'nachandra', using password. Request: /auth

[1]+ Segmentation fault sudo /usr/bin/maxscale -d -lstdout -U maxscale
[root@testans401 ~]#
[root@testans401 ~]#
[root@testans401 ~]# ps -ef|grep maxscale
root 83691 82112 0 21:30 pts/6 00:00:00 grep --color=auto maxscale
[root@testans401 ~]# coredumpctl
No coredumps found.
[root@testans401 ~]# sysctl kernel.core_pattern
kernel.core_pattern = core
[root@testans401 ~]# ls -lrth /usr/lib/systemd/systemd-coredump*
-rwxr-xr-x 1 root root 130K Jan 13 2022 /usr/lib/systemd/systemd-coredump
[root@testans401 ~]#
[root@testans401 ~]#
[root@testans401 ~]# ls -lrht /usr/bin/maxscale/
ls: cannot access /usr/bin/maxscale/: Not a directory
[root@testans401 ~]#
[root@testans401 ~]# ls -lrht /var/lib/systemd/coredump/
total 0
[root@testans401 ~]#

Could you try doing the test again but this time with the debug packages? You can find the debug version of the 23.02.1 release here: https://dlm.mariadb.com/2900358/MaxScale/23.02.1-debug/packages/rhel/7/x86_64/maxscale-23.02.1-1.rhel.7.x86_64.rpm

Another option is to run MaxScale under gdb and see if that catches the problem. Use this to start GDB:

sudo gdb /usr/bin/maxscale

Then use this GDB command to start MaxScale:

r -d -lstdout -U maxscale

Once it hits that problem, run this command to print the stacktrace:

bt

The stacktrace should show where the problem originates from.

naresh.chandra@copart.com any updates?

naresh.chandra@copart.com have you been able to reproduce this outside of a production environment? If you have, can you provide a test case that we can use to reproduce this?

We'll need information on how to reproduce this or at least a stacktrace to see where the problem is. Right now there's not much to go on so I closed this as Incomplete. Once we have some information or it can be reproduced on another system, we can reopen this issue.