lastlog

size can specify bytes (default) and KB (Sizek) or MB (sizem). Second, the default configuration LogrotateLogrotate default configuration/etc/logrotate.conf.The file contents of the Red Hat Linux default installation are:# see ' Man logrotate ' for details# Rotate log Files WeeklyWeekly# Keep 4 weeks worth of backlogsRotate 4# Send errors to rootErrors Root# Create new (empty) log files after rotating old onesCreate# Uncomment this if you want your log files compressed#compress1# RPM Packages D

Importance of the login file To resolve system errors: Solve the problem of network service; Past Event Log book: Linux Common Login file name /var/log/cron: Is your crontab schedule actually being carried out? Did the process occur without errors? Is your/etc/crontab written correctly? Check in this log in file. /VAR/LOG/DMESG: Record the information generated by the core detection process when the system is powered on. Be

example: Mail rootCommand name: LastCommand path:/usr/bin/lastExecute Permissions: All UsersSyntax: LastFunction Description: Lists the current and past logged in system User Information example: lastCommand name: LastlogCommand path:/usr/bin/lastlogExecute Permissions: All UsersSyntax: LastlogFunction Description: Check the last login time for a specific user example: Lastlog lastlog-u 502 (502 for user I

permissions mechanism. /var/log/boot.log -Contains the log at system startup. /var/log/daemon.log -Contains various system daemon log information. /var/log/dpkg.log – includes installation or DPKG command to clear the log of the package. /var/log/kern.log – Contains logs generated by the kernel to help resolve issues when customizing the kernel. /var/log/lastlog -Records the most recent information for all users. This is not an ASCII file,

who's online Last recent landing of the host information Lastlog recently logged in to read/var/log/lastlog Talk Chat with other users Write send message write test [ctrl]+d send MESG Set Terminal Write permission MESG n prohibit receiving MESG y Wall send information to all users wall this is Q test Mail Write Mail /etc/default/useradd Home Directory default settings Quota shows the space used by the disk

by the kernel to help resolve problems while customizing the kernel./var/log/lastlog-records the most recent information for all users. This is not an ASCII file, so you need to view the content with the Lastlog command./var/log/maillog/var/log/mail.log-contains the log information for the system to run the e-mail server. For example, the SendMail log information is all sent to this file./var/log/user.log-

and the printing of the last login and the ' Day '. Otherwise if the file "Var/log/lastlog" exists the ' last login ' is printed and then the ' current login ' recorded in th is file. Is the current login recorded in this file if it does not already exist or if the file ". Hushlogin" exists? I do it does but have found no documentation that says. At this point the login program would perform standard administrative tasks. These include:setting the UI

this command does not, it is difficult to find, all the groups in the system. Second, user action 1, Increase user View copy print? [Root@krlcgcms01 mytest]# Useradd–help Usage:useradd [Options] LOGIN Options: -b,–base-dir Base_dir set basic path as user's login directory -c,–comment comment comments to the user -d,–home-dir Home_dir Set the user's login directory -d,–defaults Change settings -e,–expiredate Expire_date Set the user's expiration date -f,–inactive The password

/DMESGMail system/var/log/maillogUser Login/var/log/lastlog;/var/log/secure;/var/log/wtmp;/var/run/btmp 2. Kernel and system logsUnified management by System service RSYSLOGDPackage: rsyslog-5.8.10-8.el6.x86_64Main program:/SBIN/RSYSLOGDConfiguration file:/etc/rsyslog.confLevel of log messages0 Emerg (Emergency): causes the host system to become unusable1 alert (warning): A problem that must be taken immediate action to resolve2 Crit (severe): mo

(the database file of the last command), which is a data file at the time of the file. Read through the last command, the Cat command will read garbled, because he book order a special format file. Lastlog (/var/log/lastlog)Add: You can view file types by using the files command[Email protected] ~]# File/bin/cat/bin/cat:elf 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared li

-19 02:46Root pts/0 2017-04-19 03:19 (192.168.146.1)"Attached": see who is currently logged on userWHOAMI (no spaces between letters)650) this.width=650; "src=" Https://s2.51cto.com/wyfs02/M02/91/A2/wKioL1j3JQqBZVmiAAAKsK3UYMg466.png "title=" Whoami.png "alt=" Wkiol1j3jqqbzvmiaaaksk3uymg466.png "/>3. Lastlog command to view the users on the host650) this.width=650; "src=" Https://s1.51cto.com/wyfs02/M02/91/A3/wKiom1j3JC-RfSUQAACPruqRJeA858.png "title=

Linux logsLinux logs are mostly stored in clear text, generally stored in the/var/log directory, Linux system mainly has three log subsystem: Connection time log, process statistics log, error log.Connection Time LogThe connection time log is executed by several programs, logging the log to/var/log/wtmp/var/run/utmp/var/log/lastlog three files, these three files record the user login system and the information about the exit, Utmp saves each user's in

command is not, it is difficult to find, all the groups in the system.Two, user operation1, increase the userView copy print?[Email protected] mytest]# Useradd–helpUsage:useradd [Options] LOGINOptions:-b,–base-dir Base_dir Set the base path as the user's logon directory-c,–comment comment comments to the user-d,–home-dir Home_dir Setting the user's login directory-d,–defaults changing settings-e,–expiredate Expire_date Set the user's validity period-f,–inactive inactive user expires, make passw

enters or issues the system./var/log/lastlog: Recent successful logon events and the last unsuccessful logon event ./var/log/rpmpkgs: records the list of RPM packages installed in the system./var/log/secure: record the event information during user logon authentication ./var/log/wtmp: Log Each user logon, logoff, and system startup and shutdown events ./var/run/utmp: records the details of each user who is currently logged on .Second, log file analys

root privilegesLast command search wtmp to show users who have logged in since the first time the file was created, found the illegal user, and processed it.[Email protected]]# lastDevin PTS/1 10.0.2.221 Mon Jul 15:08-down (8+17:46)Devin PTS/1 10.0.2.221 Mon Jul 21 14:42-14:53 (00:11)Changyi PTS/2 10.0.2.141 Mon Jul 21 14:12-14:12 (00:00)Devin PTS/1 10.0.2.221 Mon Jul 21 12:51-14:40 (01:49)Reboot system boot 2.4.18 Fri Jul 18 15:42 (11+17:13)You can display their login information by indicating

The login file can help us understand many of the system's important events, including some information about the login, so the permissions to log in to the file are usually set to read only by Root . and because the login file can record the system so much more detailed information, so, an experienced host administrator will be on the go to check their own log files, to keep abreast of the system's latest pulse! So what are some of the most common log files? Generally, there are several: ?? /v

, do not add the user to the Lastlog file-M, do not create the login directory automatically-R, set up the system account-o,–non-unique allows the user to have the same UID-p,–password password using encrypted passwords for new users-s,–shell Shell login Time Shell-u,–uid UID Specifies a UID for the new user-z,–selinux-user Seuser Use a specific seuser for the SELinux user mapping[email protected] mytest]# useradd--helpusage:useradd [options] LOGINOpt

size, and size can specify bytes (default) and KB (Sizek) or MB (sizem). Second, the default configuration LogrotateLogrotate default configuration/etc/logrotate.conf.The file contents of the Red Hat Linux default installation are:# see ' Man logrotate ' for details# Rotate log Files WeeklyWeekly# Keep 4 weeks worth of backlogsRotate 4# Send errors to rootErrors Root# Create new (empty) log files after rotating old onesCreate# Uncomment this if you want your log files compressed#compress1# RPM

program. You can use this tool to edit all wtmp or utmp types of files.Z2Utmp/wtmp/lastlog Log Cleanup Tool. You can delete all entries for a user name in the Utmp/wtmp/lastlog log file. However, if the Linux system needs to manually modify its source code, set the location of the log file.File creation Time Several file-related time: 1, Access time, read the contents of this file, this time will be upda

Linux system logs are generally placed in the/var/log directory, for the understanding of this directory of the role of the document is very important, I would like to list some of the work commonly used in the log document, and the role of the file, I hope to help you, record down to oneself also convenient:/var/log: Common directory, The directory dedicated to storing all log files, which contains a lot of system, software, users and other related log information; there are some files that are