fluent-plugin-systemd fails with SIGABORT on Ubuntu 21.04

[scrwr]

When using fluent-plugin-systemd the worker crashes hard with a SIGABRT. Initially we assumed it to be a problem with the plugin, but it turned out to be related to libjemalloc. After removing

Environment=LD_PRELOAD=/opt/td-agent/lib/libjemalloc.so

from the service, crashes are gone.

See https://github.com/ledbettj/systemd-journal/issues/93 for more details.

We were using td-agent 3 in the above example, but the issue is the same with td-agent 4.

Some more info:

• Ubuntu 21.10
• td-agent 4.3.0-1 from http://packages.treasuredata.com/4/ubuntu/focal/

Related config part:

<source>
  @type systemd
  tag systemd
  path /var/log/journal
  <storage>
    @type local
    persistent true
    path /var/tmp/fluentd_systemd
  </storage>
  <entry>
    fields_strip_underscores true
    fields_lowercase true
  </entry>
</source>

Let me know, in case I can help with further details.

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[github-actions[bot]]

This issue was automatically closed because of stale in 30 days

[daipom]

Seems like this problem still exists.

Environment

• Ubuntu 22.04
• td-agent 4.4.1 fluentd 1.15.2 (c32842297ed2c306f1b841a8f6e55bdd0f1cb27f)
  • Installed by $ curl -fsSL https://toolbelt.treasuredata.com/sh/install-ubuntu-jammy-td-agent4.sh | sh

How to Reproduce

• Install fluent-plugin-systemd plugin: $ td-agent-gem install fluent-plugin-systemd
• Add the following setting

<source>
  @type systemd
  tag debug
  path /var/log/journal
  read_from_head true
</source>

• $ (sudo) adduser td-agent systemd-journal
• $ (sudo) systemctl restart td-agent

Result

• After reading one record, then the worker dies with SIGABRT.

2022-10-12 05:58:38 +0000 [info]: #0 fluentd worker is now running worker=0
2022-10-12 04:50:35.083947000 +0000 debug: {"SYSLOG_FACILITY":"3","SYSLOG_IDENTIFIER":"systemd-journald","_TRANSPORT":"driver","PRIORITY":"6","MESSAGE_ID":"f77379a8490b408bbe5f6940505a777b","MESSAGE":"Journal started","_PID":"57","_UID":"0","_GID":"0","_COMM":"systemd-journal","_EXE":"/usr/lib/systemd/systemd-journald","_CMDLINE":"/lib/systemd/systemd-journald","_CAP_EFFECTIVE":"25402800cf","_SELINUX_CONTEXT":"unconfined\n","_SYSTEMD_CGROUP":"/system.slice/systemd-journald.service","_SYSTEMD_UNIT":"systemd-journald.service","_SYSTEMD_SLICE":"system.slice","_SYSTEMD_INVOCATION_ID":"ad56283776054be3859ad9b4e1f962d5","_BOOT_ID":"eb783cbf1e3c47c0a680a80b99e356d9","_MACHINE_ID":"6981994dead5402094f9195aec951d36","_HOSTNAME":"jammy-td-agetn"}
2022-10-12 05:58:39 +0000 [error]: Worker 0 finished unexpectedly with signal SIGABRT

ETC

This doesn't reproduce on Ubuntu 20.04.

[daipom]

As @scrwr says, we can avoid this issue by commenting out the following line in /lib/systemd/system/td-agent.service

Environment=LD_PRELOAD=/opt/td-agent/lib/libjemalloc.so

Then apply this.

$ (sudo) systemctl daemon-reload
$ (sudo) systemctl restart td-agent

However, is it correct to comment out this?

[daipom]

However, is it correct to comment out this?

It is not recommended to edit directly /lib/systemd/system/td-agent.service. The correct way to change environment variables would be as follows for Ubuntu:

• Edit /etc/default/td-agent and add the following line:

LD_PRELOAD=

• Then restart td-agent: $ (sudo) systemctl restart td-agent

My concern here was the effect of omitting this environment variable, but it seems that if memory usage is not a problem, this environment variable can be omitted.

Thus, for now, this seems to be a workaround.

[mszabo]

having the same issue. workaround helped, but I wonder if there is any progress on a permanent fix?

[daipom]

I think there is no progress. We still need this workaround for fluent-plugin-systemd in some environments.

@mszabo Could you share your environment information? Are you using Ubuntu?

[mszabo]

@daipom yes, issue surfaced when we started to migrate to the latest ubuntu LTS. (22.04).

[daipom]

Thanks!

[fesia]

Hello,

Migrated my app from RHEL 8.8 to RHEL 9.2 and started experiencing the same issue:

2023-10-05 11:06:29 +0200 [error]: Worker 0 exited unexpectedly with signal SIGABRT

The workaround with unsetting LD_PRELOAD var helped. Posting my env info in case it may help with the permanent fix.

• OS: RHEL 9.2
• kernel version 5.14.0-284.30.1
• td-agent package version 4.5.1-1
• ruby version 3.1.4p223 (bundled with td-agent)
• fluent-plugin-systemd gem version 1.0.5
• systemd-journal gem version 1.4.2

Thanks, Andrii