logrotate 日志滚动的使用

最近由于最近上一个了项目，但是项目的本身没有做日志的滚动，导致日志一直在增长，这样下去肯定会撑爆磁盘，导致不可预测的结果   
这个适合logrotate就出场了

作用

 logrotate is designed to ease administration of systems that generate large numbers of log files. It allows automatic rotation, compression, removal,   
  and mailing of log files. Each log file may be handled daily, weekly, monthly, or when it grows too large.

正如man logrotate说的那样，logrotate可以实现自动轮替、压缩、删除日志、并且发邮件的功能

使用

root@49335c6e5ee3:/var/log# logrotate --help
Usage: logrotate [OPTION...] <configfile>
  -d, --debug               Don't do anything, just test (implies -v)
  -f, --force               Force file rotation
  -m, --mail=command        Command to send mail (instead of `/usr/bin/mail')
  -s, --state=statefile     Path of state file
  -v, --verbose             Display messages during rotation
  -l, --log=STRING          Log file or 'syslog' to log to syslog
      --version             Display version information

Help options:
  -?, --help                Show this help message
      --usage               Display brief usage message

也就是说，可以手动的执行 logrotate configfile 文件,那配置文件里的内容怎么设置呢，如下demo：

/var/log/cron.log {
  daily
  rotate 7
  notifempty
  create
  size 1K
  nocompress
  nodateext
  missingok
}

解释说明

具体的详细说明，参照man logrotate

运行机制

对安装了cron的系统来说,crontab会每天定时执行/etc/cron.daily目录下的脚本，而这个目录下有个文件叫logrotate :

 #!/bin/sh

test -x /usr/sbin/logrotate || exit 0
/usr/sbin/logrotate /etc/logrotate.conf

我们看到 每天会运行/usr/sbin/logrotate /etc/logrotate.conf 这个命令，
在linux上 文件/etc/logrotate.conf内容如下：

# see "man logrotate" for details
# rotate log files weekly
weekly

# use the syslog group by default, since this is the owning group
# of /var/log/syslog.
su root syslog

# keep 4 weeks worth of backlogs
rotate 4

# create new (empty) log files after rotating old ones
create

# uncomment this if you want your log files compressed
#compress

# packages drop log rotation information into this directory
include /etc/logrotate.d

# no packages own wtmp, or btmp -- we'll rotate them here
/var/log/wtmp {
    missingok
    monthly
    create 0664 root utmp
    rotate 1
}

/var/log/btmp {
    missingok
    monthly
    create 0660 root utmp
    rotate 1
}

# system-specific logs may be configured here

我们看到include /etc/logrotate.d，会把/etc/logrotate.d目录下的文件include进来，
所以对于用户来说在/etc/logrotate.d 配置文件，就可以，总结一下
logrotate的配置文件:

/etc/logrotate.d/*   
/etc/logrotate.conf