[Linux] How to check kernel logs

1. dmesg

$ dmesg
[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Initializing cgroup subsys cpuacct
[    0.000000] Linux version 3.10.0-1160.11.1.el7.x86_64 (mockbuild@kbuilder.bsys.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC) ) #1 SMP Fri Dec 18 16:34:56 UTC 2020
[    0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-3.10.0-1160.11.1.el7.x86_64 root=UUID=6691577e-a654-48c0-8efb-2c845db4c8d8 ro net.ifnames=0 biosdevname=0 console=tty0 console=ttyS0,115200n8 crashkernel=auto rhgb quiet intel_idle.max_cstate=0 processor.max_cstate=0 transparent_hugepage=never pcie_aspm.policy=performance intel_pstate=disable nospectre_v1 nospectre_v2 nopti l1tf=off nospec_store_bypass_disable mds=off no_stf_barrier mitigations=off tsx=on tsx_async_abort=off
[    0.000000] e820: BIOS-provided physical RAM map:
[    0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
[    0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved

...

2. kmsg

$ cat /dev/kmsg

or

$ cat /proc/kmsg

3. /var/log/messages

cat /var/log/messages | grep kernel