/var/log/messages文件
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linux内核启动日志::

    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 journal: Runtime journal is using 8.0M (max allowed 794.3M, trying to leave 1.1G free of 7.7G available → current limit 794.3M).
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: Initializing cgroup subsys cpuset
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: Initializing cgroup subsys cpu
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: Initializing cgroup subsys cpuacct
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: Linux version 3.10.0-693.2.2.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-16) (GCC) ) #1 SMP Tue Sep 12 22:26:13 UTC 2017
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: Command line: BOOT_IMAGE=/boot/vmlinuz-3.10.0-693.2.2.el7.x86_64 root=UUID=eb448abb-3012-4d8d-bcde-94434d586a31 ro crashkernel=auto rhgb quiet net.ifnames=0 console=tty0 console=ttyS0,115200n8
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: e820: BIOS-provided physical RAM map:
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x0000000000100000-0x00000000bffdffff] usable
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x00000000bffe0000-0x00000000bfffffff] reserved
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: BIOS-e820: [mem 0x0000000100000000-0x000000043fffffff] usable
    May 19 08:04:11 ali-bj-iot-ol-ota-a-01 kernel: NX (Execute Disable) protection: active