omsagent/omi アクティビティ中に Azure 仮想マシンが再起動したのはなぜですか?

omsagent/omi アクティビティ中に Azure 仮想マシンが再起動したのはなぜですか?

Azure で RHEL8 を実行している私の仮想マシンが数分間ダウンしていました。結局、再起動しました。テレメトリとログには問題は表示されていません。dnf 更新はなく、スケジュールされた更新ウィンドウもありませんでした。Azure サービスの正常性何も言うことはありません。公式トラブルシューティングドキュメント適用されます。では、なぜ仮想マシンが再起動したのでしょうか?

イベントの順序については 100% 確信はありませんが、唯一のヒントは Azure によって開始された再起動を示しています。Azure ポータルのアクティビティ ログには、再起動自体である「正常性イベント」が報告され、10 秒以内に解決済みとしてマークされます。

    "submissionTimestamp": "2024-01-24T05:14:50.701Z",
    "properties": {
        "title": "Reboot initiated from inside the machine",
        "details": "The Virtual Machine is undergoing a reboot as requested by a restart action triggered by an authorized user or process from within the Virtual Machine. No other action is required at this time.",
        "currentHealthStatus": "Unavailable",
        "previousHealthStatus": "Unavailable",
        "type": "Downtime",
        "cause": "UserInitiated"
    },

そのイベントが解決済みとしてマークされてから数秒後に VM が起動しました。

[Wed Jan 24 05:15:01 2024] Linux version 4.18.0-513.11.1.el8_9.x86_64 ([email protected]) (gcc version 8.5.0 20210514 (Red Hat 8.5.0-20) (GCC)) #1 SMP Thu Dec 7 03:06:13 EST 2023

約20秒後でログには、OMI/omsagent が sudo を使用していることが示されています。

Jan 24 07:15:19 <redacted> sudo[39861]: omsagent : TTY=unknown ; PWD=/opt/microsoft/omsconfig/Scripts/3.x ; USER=root ; COMMAND=/opt/microsoft/omsconfig/Scripts/OMSYumUpdates.sh

監査ログ ( ausearch --format text -if /var/log/audit/audit.log) には、前後 1 分間の omsagent からの活発なアクティビティが次のような行で表示されます。

At 05:10:17 01/24/2024 system, acting as omsagent, successfully was-authorized omsagent using /usr/bin/sudo
At 05:10:17 01/24/2024 system, acting as omsagent, successfully ran-command /opt/microsoft/omsconfig/Scripts/OMSAuditdPlugin.sh get /var/opt/microsoft/omsagent/87230cd3-6635-446c-bfc0-00e4fd6f2a13/tmp using /usr/bin/sudo
At 05:14:25 01/24/2024 system, acting as root, successfully started-service omsagent-87230cd3-6635-446c-bfc0-00e4fd6f2a13 using /usr/lib/systemd/systemd
At 05:14:25 01/24/2024 system, acting as root, successfully stopped-service omsagent-87230cd3-6635-446c-bfc0-00e4fd6f2a13 using /usr/lib/systemd/systemd
At 05:15:13 01/24/2024 system, acting as root, successfully started-service omsagent-87230cd3-6635-446c-bfc0-00e4fd6f2a13 using /usr/lib/systemd/systemd
At 05:15:16 01/24/2024 system, acting as omsagent, successfully was-authorized omsagent using /usr/bin/sudo
At 05:15:16 01/24/2024 system, acting as omsagent, successfully ran-command /opt/microsoft/omsconfig/Scripts/OMSYumUpdates.sh using /usr/bin/sudo

At 05:10:17 01/24/2024 system, acting as omsagent, successfully was-authorized omsagent using /usr/bin/sudo
At 05:10:17 01/24/2024 system, acting as omsagent, successfully ran-command /opt/microsoft/omsconfig/Scripts/OMSAuditdPlugin.sh get /var/opt/microsoft/omsagent/87230cd3-6635-446c-bfc0-00e4fd6f2a13/tmp using /usr/bin/sudo
At 05:10:17 01/24/2024 system, acting as root, successfully changed-login-id-to root 
At 05:10:17 01/24/2024 root successfully triggered-unknown-audit-rule using /usr/lib/systemd/systemd
At 05:10:17 01/24/2024 root successfully started-session ? using /usr/lib/systemd/systemd
At 05:10:17 01/24/2024 system, acting as root, successfully started-service user@0 using /usr/lib/systemd/systemd
At 05:14:24 01/24/2024 system, acting as root, successfully negotiated-crypto-key SHA256:<redacted> using /usr/sbin/sshd
At 05:14:24 01/24/2024 system, acting as root, successfully started-service libstoragemgmt using /usr/lib/systemd/systemd
At 05:14:24 01/24/2024 system, acting as root, successfully stopped-service libstoragemgmt using /usr/lib/systemd/systemd
At 05:14:24 01/24/2024 system, acting as root, successfully started-service waagent using /usr/lib/systemd/systemd
At 05:14:24 01/24/2024 system, acting as root, successfully stopped-service waagent using /usr/lib/systemd/systemd
At 05:14:24 01/24/2024 root successfully changed-auditd-configuration using signal
At 05:14:25 01/24/2024  unloaded-bpf-program 118
At 05:14:25 01/24/2024 system, acting as root, successfully started-service dracut-shutdown using /usr/lib/systemd/systemd
At 05:14:25 01/24/2024 system, acting as root, successfully stopped-service dracut-shutdown using /usr/lib/systemd/systemd
At 05:14:25 01/24/2024  unloaded-bpf-program 15 
At 05:14:25 01/24/2024 system, acting as root, successfully started-service omsagent-87230cd3-6635-446c-bfc0-00e4fd6f2a13 using /usr/lib/systemd/systemd
At 05:14:25 01/24/2024 system, acting as root, successfully stopped-service omsagent-87230cd3-6635-446c-bfc0-00e4fd6f2a13 using /usr/lib/systemd/system
At 05:14:25 01/24/2024 system, acting as root, successfully started-service gcd using /usr/lib/systemd/systemd
At 05:14:25 01/24/2024 system, acting as root, successfully stopped-service gcd using /usr/lib/systemd/systemd
At 05:14:26 01/24/2024 system, acting as root, successfully started-service mdatp using /usr/lib/systemd/systemd
At 05:14:26 01/24/2024 system, acting as root, successfully stopped-service mdatp using /usr/lib/systemd/systemd

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