Chapter 11. Contacting Red Hat support for service

1. Install the debuginfo packages if they are not installed already.

   1. Enable the following repositories to install the required debuginfo packages.

      Example

      [root@host01 ~]# subscription-manager repos --enable=rhceph-5-tools-for-rhel-8-x86_64-rpms
      [root@host01 ~]# yum --disablerepo='*' --enable=rhceph-5-tools-for-rhel-8-x86_64-debug-rpms

      Once the repository is enabled, you can install the debug info packages that you need from this list of supported packages:

      ceph-base-debuginfo
      ceph-common-debuginfo
      ceph-debugsource
      ceph-fuse-debuginfo
      ceph-immutable-object-cache-debuginfo
      ceph-mds-debuginfo
      ceph-mgr-debuginfo
      ceph-mon-debuginfo
      ceph-osd-debuginfo
      ceph-radosgw-debuginfo
      cephfs-mirror-debuginfo

2. Ensure that the gdb package is installed and if it is not, install it:

   Example

   [root@host01 ~]# dnf install gdb

   • Section 11.3.2, “Generating readable core dump files in containerized deployments”

Procedure

1. If a Ceph process terminates unexpectedly due to the SIGILL, SIGTRAP, SIGABRT, or SIGSEGV error:

   1. Set the core pattern to the systemd-coredump service on the node where the container with the failed Ceph process is running:

      Example

      [root@mon]# echo "| /usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h %e" > /proc/sys/kernel/core_pattern

   2. Watch for the next container failure due to a Ceph process and search for the core dump file in the /var/lib/systemd/coredump/ directory:

      Example

      [root@mon]# ls -ltr /var/lib/systemd/coredump
      total 8232
      -rw-r-----. 1 root root 8427548 Jan 22 19:24 core.ceph-osd.167.5ede29340b6c4fe4845147f847514c12.15622.1584573794000000.xz

2. To manually capture a core dump file for the Ceph Monitors and Ceph OSDs:

   1. Get the MONITOR_ID or the OSD_ID and enter the container:

      Syntax

      podman ps
      podman exec -it MONITOR_ID_OR_OSD_ID bash

      Example

      [root@host01 ~]# podman ps
      [root@host01 ~]# podman exec -it ceph-1ca9f6a8-d036-11ec-8263-fa163ee967ad-osd-2 bash

   2. Install the procps-ng and gdb packages inside the container:

      Example

      [root@host01 ~]# dnf install procps-ng gdb

   3. Find the process ID:

      Syntax

      ps -aef | grep PROCESS | grep -v run

      Replace PROCESS with the name of the running process, for example ceph-mon or ceph-osd.

      Example

      [root@host01 ~]# ps -aef | grep ceph-mon | grep -v run
      ceph       15390   15266  0 18:54 ?        00:00:29 /usr/bin/ceph-mon --cluster ceph --setroot ceph --setgroup ceph -d -i 5
      ceph       18110   17985  1 19:40 ?        00:00:08 /usr/bin/ceph-mon --cluster ceph --setroot ceph --setgroup ceph -d -i 2

   4. Generate the core dump file:

      Syntax

      gcore ID

      Replace ID with the ID of the process that you got from the previous step, for example 18110:

      Example

      [root@host01 ~]# gcore 18110
      warning: target file /proc/18110/cmdline contained unexpected null characters
      Saved corefile core.18110

   5. Verify that the core dump file has been generated correctly.

      Example

      [root@host01 ~]# ls -ltr
      total 709772
      -rw-r--r--. 1 root root 726799544 Mar 18 19:46 core.18110

   6. Copy the core dump file outside of the Ceph Monitor container:

      Syntax

      podman cp ceph-mon-MONITOR_ID:/tmp/mon.core.MONITOR_PID /tmp

      Replace MONITOR_ID with the ID number of the Ceph Monitor and replace MONITOR_PID with the process ID number.

3. To manually capture a core dump file for other Ceph daemons:

   1. Log in to the cephadm shell:

      Example

      [root@host03 ~]# cephadm shell

   2. Enable ptrace for the daemons:

      Example

      [ceph: root@host01 /]# ceph config set mgr mgr/cephadm/allow_ptrace true

   3. Redeploy the daemon service:

      Syntax

      ceph orch redeploy SERVICE_ID

      Example

      [ceph: root@host01 /]# ceph orch redeploy mgr
      [ceph: root@host01 /]# ceph orch redeploy rgw.rgw.1

   4. Exit the cephadm shell and log in to the host where the daemons are deployed:

      Example

      [ceph: root@host01 /]# exit
      [root@host01 ~]# ssh root@10.0.0.11

   5. Get the DAEMON_ID and enter the container:

      Example

      [root@host04 ~]# podman ps
      [root@host04 ~]# podman exec -it ceph-1ca9f6a8-d036-11ec-8263-fa163ee967ad-rgw-rgw-1-host04 bash

   6. Install the procps-ng and gdb packages:

      Example

      [root@host04 /]# dnf install procps-ng gdb

   7. Get the PID of process:

      Example

      [root@host04 /]# ps aux | grep rados
      ceph           6  0.3  2.8 5334140 109052 ?      Sl   May10   5:25 /usr/bin/radosgw -n client.rgw.rgw.1.host04 -f --setuser ceph --setgroup ceph --default-log-to-file=false --default-log-to-stderr=true --default-log-stderr-prefix=debug

   8. Gather core dump:

      Syntax

      gcore PID

      Example

      [root@host04 /]# gcore 6

   9. Verify that the core dump file has been generated correctly.

      Example

      [root@host04 /]# ls -ltr
      total 108798
      -rw-r--r--. 1 root root 726799544 Mar 18 19:46 core.6

   10. Copy the core dump file outside the container:

       Syntax

       podman cp ceph-mon-DAEMON_ID:/tmp/mon.core.PID /tmp

       Replace DAEMON_ID with the ID number of the Ceph daemon and replace PID with the process ID number.

4. Upload the core dump file for analysis to a Red Hat support case. See Providing information to Red Hat Support engineers for details.