基于 bash shell 脚本制定灵活的 trimlog 日志清理策略

前言

透过 Zabbix 文件系统监控告警发现日志未定时清理，进一步排查后确认前同事写的 trimlog 脚本在某些服务器上执行定时任务时出现了异常，review 后发现代码逻辑本身没有问题，主要由于 cron job 在执行 date 参数时没有使用转义字符导致，不过 trimlog.sh 这个日志清理脚本代码结构清晰易读，做下共享方便大家参考和二次修改。

基于 bash shell 脚本制定灵活的 trimlog 日志清理策略

更新历史

2019 年 10 月 08 日 - 初稿

阅读原文 - https://wsgzao.github.io/post/trimlog/

扩展阅读

基于 bash find 命令执行 log 日志备份和清理的一次简单实践

问题描述

# 检查 crontab
cat /etc/crontab

#Ansible: gdp_trim_log
0 1 * * * root /data/release/trimlog.sh '/data/release/log/gop_gdp' 30 1 '*' '%Y%m%d' >> /data/release/trimlog.txt
0 1 * * * root /data/release/trimlog.sh '/data/release/log/cacheupdate' 30 1 '*' '%Y%m%d' >> /data/release/trimlog.txt
#Ansible: gdp_trim_backup
0 1 * * * root /data/release/trimbackup.sh '/data/release/backup/gop_gdp' 30 >> /data/release/trimbackup.txt

# 检查 crontab 日志
less /var/log/cron

Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183782]: (root) CMD (/data/release/trimlog.sh '/data/release/log/gop_gdp' 30 1 '*' ')
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183783]: (root) CMD (/data/release/trimbackup.sh '/data/release/backup/gop_gdp' 30 >> /data/release/trimbackup.txt)
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183784]: (root) CMD (/data/release/trimlog.sh '/data/release/log/cacheupdate' 30 1 '*' ')
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183786]: (root) CMD (/usr/lib64/sa/sa1 1 1)
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183788]: (root) CMD (cd /tmp &&  ss -tna | awk '{print $1}' | sort | uniq -c > snmpss.tmp && chcon system_u:object_r
:snmpd_var_run_t:s0 snmpss.tmp && mv -f snmpss.tmp snmpss.cache)
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183779]: (root) CMDOUT (/bin/bash: -c: line 0: unexpected EOF while looking for matching `'')
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183779]: (root) CMDOUT (/bin/bash: -c: line 1: syntax error: unexpected end of file)
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183778]: (root) CMDOUT (/bin/bash: -c: line 0: unexpected EOF while looking for matching `'')
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183778]: (root) CMDOUT (/bin/bash: -c: line 1: syntax error: unexpected end of file)
Oct  8 01:00:01 sg-gop-10-71-12-146 CROND[183777]: (root) CMDOUT (find: ‘/data/release/backup/gop_gdp’: No such file or directory)

# 在 crontab 的 date 中加入转移字符即可
0 1 * * * root /data/release/trimlog.sh '/data/release/log/gop_gdp' 30 1 '*' '\%Y\%m\%d' >> /data/release/trimlog.txt
0 1 * * * root /data/release/trimlog.sh '/data/release/log/cacheupdate' 30 1 '*' '\%Y\%m\%d' >> /data/release/trimlog.txt

bash shell 代码

vim /data/release/trimlog.sh

#!/bin/bash
dir=`dirname $0`
if [ $# -lt 1 ]
then
	echo "usage: $0 DIRECTORY [DELETE_DAYS] [COMPRESS_DAYS] [COMPRESS_FILE_PATTERN] [DATE_PATTERN]"
	echo "multiple matches example for COMPRESS_FILE_PATTERN: data|error"
	exit
fi

current_date=$(date +"%Y-%m-%d %T")
echo "Start trim log at $current_date "

path=$1
if [ $# -gt 1 ]
then
	log_delete_days=$2
else
	log_delete_days=7
fi
if [ $# -gt 2 ]
then
	log_compress_days=$3
else
	log_compress_days=0
fi
if [ $# -gt 3 ]
then
	log_compress_match=$4
else
	log_compress_match='*'
fi
if [ $# -gt 4 ]
then
	date_pattern=$5
else
	date_pattern="%Y-%m-%d"
fi
if [ $log_delete_days -gt 0 ]
then
	files=`ls $path/*.log.*`
	i=0
	while [ $i -le $log_delete_days ]
	do
		d=`date "+$date_pattern" --date "$i day ago"`
		files=`echo "$files"|grep -v $d`
		i=`expr $i + 1`
	done
	echo "$files"|xargs rm -f
fi
if [ $log_compress_days -gt 0 ] && [ -n "$log_compress_match" ]
then
	files=`ls $path/*.log.*|grep -v "\.gz$"|grep -E "$log_compress_match"`
	i=0
	while [ $i -lt $log_compress_days ]
	do
		d=`date "+$date_pattern" --date "$i day ago"`
		files=`echo "$files"|grep -v $d`
		i=`expr $i + 1`
	done
	echo "$files"|xargs gzip
fi

current_date=$(date +"%Y-%m-%d %T")
echo "Finish trim log at $current_date "

vim /data/release/trimbackup.sh

#!/bin/bash
dir=`dirname $0`
if [ $# -lt 1 ]
then
	echo "usage: $0 DIRECTORY [KEEP_BACKUP_NUM]"
	exit
fi

current_date=$(date +"%Y-%m-%d %T")
echo "Start trim backup at $current_date "

path=$1
if [ $# -gt 1 ]
then
	keep_backup_num=$2
else
	keep_backup_num=10
fi

i=0
find $path -maxdepth 1 ! -path $path -type d -printf '%p\n' | sort -r -n | while read dir; do
	i=`expr $i + 1`
	if [ $i -gt $keep_backup_num ]
	then
		echo "del $dir"
		rm -rf $dir
	else
		echo "keep $dir"
	fi
done

current_date=$(date +"%Y-%m-%d %T")
echo "Finish trim backup at $current_date "