目录
常见的系统日志
/var/log/messages 记录内核消息、各种服务的公共消息
/var/log/dmesg 记录系统启动过程的各种消息
/var/log/cron 记录与cron计划任务相关的信息
/var/log/mailog 记录邮件收发相关的消息
/var/log/secure 记录与访问限制相关的安全消息
日志消息的优先级(高---->低)
EMERG(紧急):级别0,系统不可用的情况
ALERT(警报):级别1 ,必须马上采取措施的情况
CRIT(严重):级别2,严重情形
ERR(错误):级别3,出现错误
WARNING(警告) :级别4,值得警告的情形
NOTICE(注意):级别5 普通但值的引起注意的事情
INFO(信息):级别6,一般信息
DEBUG(调试):级别7 ,程序/服务调试消息
journalctl日志工具的常见用法
journalctl | grep 关键词
journalctl -u 服务器 -p 优先级
journalctl -n 消息条数
journalctl --since="yyyy-mm-dd HH:MM:SS" --until="yyyy-mm-dd HH:MM:SS"
举例:
[root@pc01 ~]# journalctl -p err -n 10
[root@pc01 ~]# journalctl --since "2017-01-06 14:11" --until "2017-01-06 19:11"
[root@pc01 ~]# journalctl -u httpd
查看硬件的信息模块
[root@pc01 ~]# dmesg | grep -i vbr
[ 62.157532] device vbr-nic entered promiscuous mode
[ 62.283506] vbr: port 1(vbr-nic) entered listening state
[ 62.283516] vbr: port 1(vbr-nic) entered listening state
[ 62.283575] IPv6: ADDRCONF(NETDEV_UP): vbr: link is not ready
[ 62.313847] vbr: port 1(vbr-nic) entered disabled state
[ 62.699983] IPv6: ADDRCONF(NETDEV_UP): vbr-nic: link is not ready
[90636.235930] vbr: port 2(vnet5) entered listening state
[90636.235939] vbr: port 2(vnet5) entered listening state
[90638.241630] vbr: port 2(vnet5) entered learning state
[90640.246914] vbr: topology change detected, propagating
[90640.246936] vbr: port 2(vnet5) entered forwarding state
[90640.247039] IPv6: ADDRCONF(NETDEV_CHANGE): vbr: link becomes ready