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日志管理相關知識

日志管理相關知識   一 日志相關文件 [plain]  #很關鍵   [root@client01 ~]# ls /var/log/   anaconda.ifcfg.log    anaconda.xlog      btmp           dmesg       maillog            secure            wtmp   anaconda.log          anaconda.yum.log   btmp-20130805  dmesg.old  maillog-20130805  secure-20130805   yum.log   anaconda.program.log  audit              ConsoleKit     dracut.log messages           spooler   anaconda.storage.log  boot.log           cron          httpd       messages-20130805  spooler-20130805   anaconda.syslog       boot.log-20130805  cron-20130805 lastlog     rhsm               tallylog       #關鍵日志,大部分記錄在裡面   [root@client01 ~]# ls /var/log/messages   /var/log/messages            #系統啟動,硬件相關日志   [root@client01 ~]# ls /var/log/dmesg*   /var/log/dmesg  /var/log/dmesg.old       #登錄安全相關日志   [root@client01 ~]# ls /var/log/secure   /var/log/secure       #使用ssh登錄,輸入錯誤密碼   [root@larrywen opt]# ssh 192.168.1.11   [email protected]'s password:   Permission denied, please try again.   [email protected]'s password:   Permission denied, please try again.       #監控文件,可以看到剛才輸入的錯誤密碼已經記錄下來了   [root@client01 ~]# tail -f /var/log/secure   [root@client01 ~]# tail -n 4/var/log/secure   Aug 5 14:46:13 client01 sshd[2796]: pam_unix(sshd:auth): authenticationfailure; logname= uid=0 euid=0 tty=ssh ruser= rhost=192.168.1.1  user=root   Aug 5 14:46:15 client01 sshd[2796]: Failed password for root from192.168.1.1 port 50116 ssh2   Aug 5 14:46:23 client01 unix_chkpwd[2800]: password check failed for user(root)   Aug 5 14:46:25 client01 sshd[2796]: Failed password for root from192.168.1.1 port 50116 ssh2       #郵件相關日志   [root@larrywen opt]# ls /var/log/maillog   /var/log/maillog       #登錄信息日志   [root@client01 ~]# ls /var/log/lastlog   #最後登錄的信息   [root@client01 ~]# ls /var/log/lastlog   /var/log/lastlog   [root@client01 ~]# last   #最後登錄錯誤的信息   [root@client01 ~]# lastb       #SELINUX相關日志   [root@client01 ~]# ls /var/log/audit/   audit.log       [root@client01 ~]# ls /var/log/maillog*   /var/log/maillog  /var/log/maillog-20130805   #之前日志的備份,一個星期切換一次,會自動備份   maillog-20130805       [root@larrywen 0805]# ls /var/log/maillog*   /var/log/maillog  /var/log/maillog-20130729  /var/log/maillog-20130805   [root@larrywen 0805]# ls /var/log/boot.log*   /var/log/boot.log  /var/log/boot.log-20130729  /var/log/boot.log-20130805     二 日志相關服務 [plain]  [root@client01 ~]# ps -ef|grep log   #系統日志服務   root      959     1  0 08:49 ?        00:00:00 /sbin/rsyslogd -c 4   root     1133     1  0 08:49 ?        00:00:00 login -- root       root     2811  2776  0 14:54 pts/0    00:00:00 grep log       [root@client01 ~]# /etc/init.d/rsyslogrestart   Shutting down system logger:                               [  OK  ]   Starting system logger:                                    [  OK  ]           #rsyslog:日志記錄的位置,指定輸出文件   #日志級別:Debug Warning     三 實驗:日志轉移(一台機器的日志備份到另一台機器)   client01: [plain]  [root@client01 ~]# ls /etc/*log*   /etc/csh.login  /etc/login.defs  /etc/logrotate.conf  /etc/rsyslog.conf       /etc/logrotate.d:   dracut httpd  subscription-manager  syslog up2date  yum   [root@client01 ~]# ls /etc/rsyslog.conf   /etc/rsyslog.conf   [root@client01 ~]# vim /etc/rsyslog.conf       #模塊:實現某個功能的程序       #不要急著寫,支持異步寫。等到一定量的時候才寫,延遲寫(負號的含義)   -/var/log/maillog       #修改文件   [root@client01 ~]# vim /etc/rsyslog.conf       [root@client01 ~]# grep "hongyi"/etc/rsyslog.conf -n   60:local3.*                                      /var/log/hongyi.log   #重啟服務   [root@client01 ~]# /etc/init.d/rsyslogrestart   Shutting down system logger:                               [  OK  ]   Starting system logger:                                    [  OK  ]   #可以查看到生成了這個文件   [root@client01 ~]# ls /var/log/hongyi.log   /var/log/hongyi.log   #寫日志   [root@client01 ~]# logger -p"local3.info" "this is test"   [root@client01 ~]# cat /var/log/hongyi.log   Aug 5 15:17:00 client01 root: this is test   #我們寫local2.info,發現沒有記錄   [root@client01 ~]# logger -p"local2.info" "this is test"   [root@client01 ~]# cat /var/log/hongyi.log   Aug 5 15:17:00 client01 root: this is test       [root@client01 ~]# logger --help   logger: invalid option -- '-'   usage: logger [-is] [-f file] [-p pri] [-ttag] [-u socket] [ message ... ]       #性能       #一台機器上的文件保存到另一台機器上   [root@serv02 ~]# grep "UDP" /etc/rsyslog.conf  -n -A1   12:# Provides UDP syslog reception   13-$ModLoad imudp.so   14:$UDPServerRun 514   15-   [root@serv02 ~]# grep "local3.*"/etc/rsyslog.conf  -n   59:local3.*                                      /tmp/up.log   [root@larrywen 0805]# man rsyslog.conf     serv01: [plain]  #rsyslog.conf做如下配置   [root@serv01 ~]# grep local3/etc/rsyslog.conf -n   #192.168.1.12是serv02的IP   #@:UDP 服務   #@@:TCP服務   60:local3.*     @192.168.1.12   #重啟服務   [root@serv01 ~]# /etc/init.d/rsyslogrestart   Shutting down system logger:                               [  OK  ]   Starting system logger:                                    [  OK  ]   #Serv02配置完後,輸出日志到第二台機器   [root@serv01 ~]# logger -p"local3.info" "hello,world"     serv02: [plain]  #rsyslog.conf文件做如下配置   [root@serv02 ~]# cat -n/etc/rsyslog.conf|sed "8,9p;/local3/p"  -n       8  $ModLoad imuxsock.so    # provides support for local system logging(e.g. via logger command)       9  $ModLoad imklog.so # provides kernel logging support (previouslydone by rklogd)   59   local3.*     /tmp/up.log   #重啟服務   [root@serv02 ~]# /etc/init.d/rsyslogrestart   Shutting down system logger:                               [  OK  ]   Starting system logger:                                    [  OK  ]   #查看文件可以看到   [root@serv02 ~]# cat /tmp/up.log   Aug 5 15:31:38 serv01 root: hello,world       #日志備份     四 定時計劃任務 [plain]  [root@client01 ~]# yum install at -y   [root@client01 ~]# at now +3 minutes   at> echo "hello,wolrd" >/opt/aa01.txt   at> <EOT>   job 2 at 2013-08-05 16:20   Can't open /var/run/atd.pid to signal atd.No atd running?   [root@client01 ~]# /etc/init.d/atd start   Starting atd:                                              [  OK  ]   #相對當前時間   [root@client01 ~]# at now +3 minutes   at> echo "hello,wolrd" >/opt/aa01.txt   at> <EOT>   job 3 at 2013-08-05 16:21   [root@client01 ~]# at -l   3     2013-08-0516:21 a root:     2     2013-08-0516:20 a root   root@client01 opt]# ll   total 20   -rw-r--r--. 1 root root    12 Aug 5 16:20 aa01.txt   drwx------. 2 root root 16384 Jul 23 00:54lost+found       #支持分鐘 小時 天   [root@client01 ~]# at now +1 days           [root@client01 opt]# at 16:28 08/05/2013   at> echo "hello,uplooking"> /opt/aa02.txt   at> <EOT>   job 4 at 2013-08-05 16:28   [root@client01 opt]# at -l   4     2013-08-0516:28 a root       [root@client01 opt]# at 18:20 08/06/2013   at> rm -rf /*<EOT>   job 5 at 2013-08-06 18:20   [root@client01 opt]# at -l   5     2013-08-0618:20 a root   4     2013-08-0516:28 a root       [root@client01 opt]# at --help   at: invalid option -- '-'   Usage: at [-V] [-q x] [-f file] [-mldbv]time         at -c job ...         atq [-V] [-q x]         atrm [-V] job ...         batch   #移除   [root@client01 opt]# atrm 5   #列出詳細的任務   [root@client01 opt]# at -l   4     2013-08-0516:28 a root       #執行完後自動清除,本次有效       #crontab:循環有效   [root@client01 opt]# vim /etc/crontab      ** * * * echo `date` >> /opt/aa03.txt   #添加規則   [root@client01 opt]# crontab -e   no crontab for root - using an empty one   crontab: installing new crontab       30 18 * * * init 0   1 */2 10-20 7,8 5 wall "Have aholiday"   #列出所有的任務   [root@client01 opt]# crontab -l   * * * * * echo `date` >>/opt/aa03.txt   30 18 * * * init 0   [root@client01 opt]# crontab --help   crontab: invalid option -- '-'   crontab: usage error: unrecognized option   usage:    crontab[-u user] file          crontab[-u user] [ -e | -l | -r ]                 (defaultoperation is replace, per 1003.2)          -e    (edit user's crontab)          -l     (list user's crontab)          -r    (delete user's crontab)          -i     (prompt before deleting user's crontab)          -s    (selinux context)       #查看編寫的文件   [root@client01 opt]# cd /var/spool/   [root@client01 spool]# ls   anacron at  cron  lpd mail  plymouth  postfix up2date   [root@client01 spool]# cd cron/   [root@client01 cron]# ll   total 4   -rw-------. 1 root root 58 Aug  5 16:37 root   [root@client01 cron]# cat root   * * * * * echo `date` >>/opt/aa03.txt   30 18 * * * init 0   [root@client01 cron]# cd /etc/cron.   cron.d/       cron.daily/   cron.deny    cron.hourly/  cron.monthly/cron.weekly/            #每天執行的   [root@client01 cron]# cat/etc/cron.d/0hourly   SHELL=/bin/bash   PATH=/sbin:/bin:/usr/sbin:/usr/bin   MAILTO=root   HOME=/   01 * * * * root run-parts /etc/cron.hourly       #每個小時執行的   [root@client01 cron]# cat/etc/cron.hourly/0anacron   #!/bin/bash   #in case file doesn't exist   if test -r /var/spool/anacron/cron.daily;then      day=`cat /var/spool/anacron/cron.daily`   fi   if [ `date +%Y%m%d` = "$day" ];then      exit 0;   fi       # in case anacron is already running,   # there will be log (daemon won't berunning twice).   if test -x /usr/bin/on_ac_power; then      /usr/bin/on_ac_power &> /dev/null      if test $? -eq 1; then      exit 0      fi   fi   /usr/sbin/anacron -s       #查看每天執行的配置文件   [root@client01 cron]# cat/etc/cron.daily/logrotate   #!/bin/sh       /usr/sbin/logrotate /etc/logrotate.conf>/dev/null 2>&1   EXITVALUE=$?   if [ $EXITVALUE != 0 ]; then      /usr/bin/logger -t logrotate "ALERT exited abnormally with[$EXITVALUE]"   fi   exit 0       #查看syslog文件,可以看到日志的創建過程   [root@client01 logrotate.d]# cat syslog   /var/log/messages /var/log/secure/var/log/maillog /var/log/spooler /var/log/boot.log /var/log/cron {      sharedscripts      postrotate          /bin/kill-HUP `cat /var/run/syslogd.pid 2> /dev/null` 2> /dev/null || true      endscript   }       #可以對日志的相關文件進行配置   [root@client01 cron]# cat/etc/logrotate.conf   # see "man logrotate" for details   # rotate log files weekly   weekly       # keep 4 weeks worth of backlogs   rotate 4       # create new (empty) log files afterrotating old ones   create       # use date as a suffix of the rotated file   dateext       # uncomment this if you want your log filescompressed   #compress       # RPM packages drop log rotationinformation into this directory   include /etc/logrotate.d       # no packages own wtmp and btmp -- we'llrotate them here   /var/log/wtmp {      monthly      create 0664 root utmp          minsize1M      rotate 1   }       /var/log/btmp {      missingok      monthly      create 0600 root utmp      rotate 1   }       # system-specific logs may be also beconfigured here.     五 模擬日志文件的拷貝 [plain]  #從man中進行示例的拷貝   [root@client01 logrotate.d]# manlogrotate.conf       #編輯文件   [root@client01 logrotate.d]# vim/etc/logrotate.conf   [root@client01 logrotate.d]# cat/etc/logrotate.conf   /opt/hongyi.log {      monthly      rotate 2      olddir /opt/old      missingok      create 0600 root hongyi      nocompress   }   #創建用戶   [root@client01 logrotate.d]# useradd hongyi   #創建目錄   [root@client01 logrotate.d]# mkdir /opt/old   #創建文件   [root@client01 logrotate.d]# touch/opt/hongyi.log   #編輯文件   [root@client01 logrotate.d]# vim/opt/hongyi.log   [root@client01 logrotate.d]# ls /opt   aa03.txt hongyi.log  old       [root@client01 logrotate.d]# 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 sendmail (instead of `/bin/mail')     -s,--state=statefile     Path of state file     -v,--verbose             Display messagesduring rotation       Help options:     -?,--help                Show this helpmessage    —usage                   Displaybrief usage message   #強制使配置文件生效   [root@client01 logrotate.d]# logrotate -f/etc/logrotate.conf   [root@client01 logrotate.d]# ls /opt   aa03.txt hongyi.log  old   #可以看到已經生成了文件   [root@client01 logrotate.d]# ls /opt/old/   hongyi.log-20130805   #日志輪尋   #日志切換       [root@client01 ~]# ls /etc/cron.d   cron.d/    cron.daily/ cron.deny   #查看每天切換的    [root@client01 ~]# ls /etc/cron.daily/   logrotate makewhatis.cron  rhsm-complianced   [root@client01 ~]# cat/etc/cron.daily/logrotate   #!/bin/sh       /usr/sbin/logrotate /etc/logrotate.conf>/dev/null 2>&1   EXITVALUE=$?   if [ $EXITVALUE != 0 ]; then      /usr/bin/logger -t logrotate "ALERT exited abnormally with[$EXITVALUE]"   fi   exit 0   [root@client01 ~]# cat /etc/logrotate.conf   # see "man logrotate" for details   # rotate log files weekly   weekly       # keep 4 weeks worth of backlogs   rotate 4       # create new (empty) log files afterrotating old ones   create       # use date as a suffix of the rotated file   dateext       # uncomment this if you want your log filescompressed   #compress       # RPM packages drop log rotationinformation into this directory   include /etc/logrotate.d       # no packages own wtmp and btmp -- we'llrotate them here   /var/log/wtmp {      monthly      create 0664 root utmp          minsize1M      rotate 1   }       /var/log/btmp {      missingok      monthly      create 0600 root utmp      rotate 1   }       /opt/hongyi.log {      monthly      rotate 2      olddir /opt/old      missingok      create 0600 root hongyi      nocompress   }       # system-specific logs may be also beconfigured here.   [root@client01 ~]# cd /etc/lo   localtime       login.defs      logrotate.conf  logrotate.d/      [root@client01 ~]# cd /etc/logrotate.d/   [root@client01 logrotate.d]# ll   total 24   -rw-r--r--. 1 root root 103 Apr 27  2011 dracut   -rw-r--r--. 1 root root 185 Jun 24  2010 httpd   -rw-r--r--. 1 root root  71 May 5  2011 subscription-manager   -rw-r--r--. 1 root root 228 May 20  2009 syslog   -rw-r--r--. 1 root root  32 Apr 8  2010 up2date   -rw-r--r--. 1 root root 100 Apr 29  2011 yum       #程序切換 日志切換   #日志:很重要            #設置日期   [root@client01 opt]# date -s"2013-08-07"   Wed Aug 7 00:00:00 CST 2013   #強制使文件生效,v顯示過程   [root@client01 opt]# logrotate -fv/etc/logrotate.conf   reading config file /etc/logrotate.conf   including /etc/logrotate.d   reading config file dracut   reading config info for /var/log/dracut.log   reading config file httpd   reading config info for /var/log/httpd/*log   reading config file subscription-manager   reading config info for /var/log/rhsm/*.log   reading config file syslog   reading config info for /var/log/messages/var/log/secure /var/log/maillog /var/log/spooler /var/log/boot.log/var/log/cron   reading config file up2date   reading config info for /var/log/up2date   reading config file yum   reading config info for /var/log/yum.log   reading config info for /var/log/wtmp   reading config info for /var/log/btmp   reading config info for /opt/hongyi.log   olddir is now /opt/old       Handling 9 logs       rotating pattern: /var/log/dracut.log  forced from command line (4 rotations)   empty log files are not rotated, old logsare removed   considering log /var/log/dracut.log     logdoes not need rotating       rotating pattern: /var/log/httpd/*log  forced from command line (4 rotations)   empty log files are not rotated, old logsare removed   considering log /var/log/httpd/access_log     logdoes not need rotating   considering log /var/log/httpd/error_log     logdoes not need rotating   not running postrotate script, since nologs were rotated       rotating pattern: /var/log/rhsm/*.log  forced from command line (4 rotations)   empty log files are not rotated, old logsare removed   considering log /var/log/rhsm/rhsmcertd.log     logdoes not need rotating   considering log /var/log/rhsm/rhsm.log     logdoes not need rotating       rotating pattern: /var/log/messages/var/log/secure /var/log/maillog /var/log/spooler /var/log/boot.log/var/log/cron  forced from command line(4 rotations)   empty log files are rotated, old logs areremoved   considering log /var/log/messages     logneeds rotating   considering log /var/log/secure     logneeds rotating   considering log /var/log/maillog     logneeds rotating   considering log /var/log/spooler     logneeds rotating   considering log /var/log/boot.log     logneeds rotating   considering log /var/log/cron     logneeds rotating   rotating log /var/log/messages,log->rotateCount is 4   dateext suffix '-20130807'   glob pattern '-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   rotating log /var/log/secure,log->rotateCount is 4   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   rotating log /var/log/maillog,log->rotateCount is 4   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   rotating log /var/log/spooler,log->rotateCount is 4   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   rotating log /var/log/boot.log,log->rotateCount is 4   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   rotating log /var/log/cron,log->rotateCount is 4   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   fscreate context set to system_u:object_r:var_log_t:s0   renaming /var/log/messages to/var/log/messages-20130807   creating new /var/log/messages mode = 0600uid = 0 gid = 0   fscreate context set tosystem_u:object_r:var_log_t:s0   renaming /var/log/secure to/var/log/secure-20130807   creating new /var/log/secure mode = 0600uid = 0 gid = 0   fscreate context set tosystem_u:object_r:var_log_t:s0   renaming /var/log/maillog to/var/log/maillog-20130807   creating new /var/log/maillog mode = 0600uid = 0 gid = 0   fscreate context set tosystem_u:object_r:var_log_t:s0   renaming /var/log/spooler to/var/log/spooler-20130807   creating new /var/log/spooler mode = 0600uid = 0 gid = 0   fscreate context set tosystem_u:object_r:var_log_t:s0   renaming /var/log/boot.log to/var/log/boot.log-20130807   creating new /var/log/boot.log mode = 0644uid = 0 gid = 0   fscreate context set tosystem_u:object_r:var_log_t:s0   renaming /var/log/cron to/var/log/cron-20130807   creating new /var/log/cron mode = 0600 uid= 0 gid = 0   running postrotate script       rotating pattern: /var/log/up2date  forced from command line (4 rotations)   empty log files are rotated, old logs areremoved   considering log /var/log/up2date     log/var/log/up2date does not exist -- skipping       rotating pattern: /var/log/yum.log  forced from command line (4 rotations)   empty log files are not rotated, old logsare removed   considering log /var/log/yum.log     logdoes not need rotating       rotating pattern: /var/log/wtmp  forced from command line (1 rotations)   empty log files are rotated, only log files>= 1048576 bytes are rotated, old logs are removed   considering log /var/log/wtmp     logneeds rotating   rotating log /var/log/wtmp,log->rotateCount is 1   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   fscreate context set to system_u:object_r:wtmp_t:s0   renaming /var/log/wtmp to/var/log/wtmp-20130807   creating new /var/log/wtmp mode = 0664 uid= 0 gid = 22   removing old log /var/log/wtmp-20130806       rotating pattern: /var/log/btmp  forced from command line (1 rotations)   empty log files are rotated, old logs areremoved   considering log /var/log/btmp     logneeds rotating   rotating log /var/log/btmp,log->rotateCount is 1   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   fscreate context set to system_u:object_r:faillog_t:s0   renaming /var/log/btmp to/var/log/btmp-20130807   creating new /var/log/btmp mode = 0600 uid= 0 gid = 22   removing old log /var/log/btmp-20130806       rotating pattern: /opt/hongyi.log  forced from command line (2 rotations)   olddir is /opt/old, empty log files arerotated, old logs are removed   considering log /opt/hongyi.log     logneeds rotating   rotating log /opt/hongyi.log,log->rotateCount is 2   dateext suffix '-20130807'   glob pattern'-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'   fscreate context set tounconfined_u:object_r:usr_t:s0   renaming /opt/hongyi.log to/opt/old/hongyi.log-20130807   creating new /opt/hongyi.log mode = 0600uid = 0 gid = 500   removing old log/opt/old/hongyi.log-20130805       #可以查看old目錄下的文件   [root@client01 opt]# ls old/   hongyi.log-20130806  hongyi.log-20130807   [root@client01 opt]# cat hongyi.log   #查看文件的權限   [root@client01 opt]# ll   total 8   -rw-r--r--. 1 root root   2436 Aug 7 00:01 aa03.txt   -rw-------. 1 root hongyi    0 Aug 7 00:00 hongyi.log   drwxr-xr-x. 2 root root   4096 Aug 7 00:00 old     六 crontab——定時任務 [plain]  #延時執行,系統啟動後,檢測還沒有執行的任務。計劃任務   #什麼時候啟動機器,什麼時候檢測   [root@client01 opt]# cat /etc/anacrontab   # /etc/anacrontab: configuration file foranacron       # See anacron(8) and anacrontab(5) fordetails.       SHELL=/bin/sh   PATH=/sbin:/bin:/usr/sbin:/usr/bin   MAILTO=root   # the maximal random delay added to thebase delay of the jobs   RANDOM_DELAY=45   # the jobs will be started during thefollowing hours only   START_HOURS_RANGE=3-22       #period in days   delay in minutes   job-identifier   command   1     5     cron.daily            nicerun-parts /etc/cron.daily   7     25   cron.weekly         nicerun-parts /etc/cron.weekly   @monthly 45      cron.monthly              nice run-parts /etc/cron.monthly       #crontab:列出和刪除   [root@client01 opt]# crontab -l   * * * * * echo `date` >>/opt/aa03.txt   30 18 * * * init 0   [root@client01 opt]# crontab --help   crontab: invalid option -- '-'   crontab: usage error: unrecognized option   usage:    crontab[-u user] file          crontab[-u user] [ -e | -l | -r ]                 (defaultoperation is replace, per 1003.2)          -e    (edit user's crontab)          -l     (list user's crontab)          -r    (delete user's crontab)          -i     (prompt before deleting user's crontab)          -s    (selinux context)   [root@client01 opt]# crontab -r   [root@client01 opt]# crontab -l   no crontab for root    
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