Table of Contents
What permissions should var log have?
The RHEL 8 /var/log/messages file must have mode 0640 or less permissive.
What is wtmp in var log?
On the Linux, Solaris, and BSD operating systems, wtmp is a file containing a history of all logins and logouts. On Linux systems, it is located at /var/log/wtmp. Various commands access wtmp to report login statistics, including the who and lastb commands.
How do I give permission to log in Linux?
Log File Permissions
- Open a terminal and switch to root using “su” or “sudo -s”.
- Run the following commands depending on the scenario: Zend Server on Nginx. chmod o+r /var/log/nginx/{access,error}.log. Zend Server on Apache. Enterprise Linux 5/6/7: chmod o+x /var/log/httpd. Debian / Ubuntu: chmod o+x /var/log/apache2.
Can you read var log messages as a regular user?
Yes it is, but note that regular users don’t have permission to read /var/log/messages and /var/log/secure .
What does wtmp stand for?
WTMP
| Acronym | Definition |
|---|---|
| WTMP | Water Temperature |
What does wtmp and utmp files maintain?
utmp, wtmp and btmp utmp maintains a full accounting of the current status of the system, system boot time (used by uptime), recording user logins at which terminals, logouts, system events etc.
How do I change permissions on var log messages in Linux?
For CentOS/RHEL 6 and 7 (using rsyslogd version >3)
- Check the current permissions of the /va/log/messages file:
- Edit the /etc/rsyslog.
- Lets move the current /var/log/messages file to some other location.
- Restart the rsyslog service to generate a new /var/log/messages file.
- Check the permission of the file again.
How do I access var log messages?
Linux logs will display with the command cd/var/log. Then, you can type ls to see the logs stored under this directory. One of the most important logs to view is the syslog, which logs everything but auth-related messages. Issue the command var/log/syslog to view everything under the syslog.
How do I manage var log messages in Linux?
Firstly, you need to open the command-line shell via the shortcut key “Ctrl+Alt+T”. After opening it, we will be utilizing the “tail” command with the “-f” flag to check the logs in the “/var/log/messages”.
What happens if var log is full?
If logs are being spammed with errors or if there are debugs enabled, a log file may become too large for logrotate to copy and compress if /var/log is too low on space. This will result in archive files being created, but once space is maxed out, logrotate cannot complete.
What is var log messages in Linux?
The folder /var/log/messages contain a variety of messages, such as mail, kern, auth, cron, daemon, and so on. Linux log data is a useful debugging utility whenever you run into problems with the Linux operating system, programs, or server. They give a chronology of the Linux system, apps, and framework actions.
What does var log lastlog do?
The /var/log/lastlog file is used to store information about the successful logins to the host. On several versions of RedHat Enterprise Linux and Fedora, corruption in this file can cause the size to be misrepresented. This has no effect on the real space used by the file, as reported by the du command.
How do you configure permissions of log files created by Rsyslog?
What is in var log messages?
This folder contains overall system notifications and messages recorded at system boot. The folder /var/log/messages contain a variety of messages, such as mail, kern, auth, cron, daemon, and so on.
How do I read wtmp?
We can also use the last command to read the content of the files wtmp, utmp and btmp as well. For example: # last -f /var/log/wtmp ### To open wtmp file and view its content use blow command. # last -f /var/run/utmp ### To see still logged in users view utmp file use last command.
Can I delete var log wtmp?
Logrotating the wtmp file : Althrough by defauld the /var/log/wtmp file will be reset each month , it can be configured to maintain his information for more than one month . This can be configured through the logrotate.
How do I change permissions on a log file?
Because a user ID with UID 0 must run syslogd, the owner is always a superuser. To change the default permissions used by syslogd, use either the -F or the -D start option to set the global default permissions for files and directories, respectively.
How do I give file permission to user and directory?
To change file and directory permissions, use the command chmod (change mode). The owner of a file can change the permissions for user ( u ), group ( g ), or others ( o ) by adding ( + ) or subtracting ( – ) the read, write, and execute permissions.
How do I read a log file?
Double-click on the log file and it will likely open in a text program by default, or you can choose the program you’d like to use to open the file by using the right-click and “Open With” option. Another option is to use a web browser and open the server log file in HTML.
Is it safe to delete lastlog?
Most likely you do not need to clear lastlog or be concerned with how much it is being written to at all. lastlog is a binary file that contains information about the last time a user logged in, I would always recommend copying the file to a partition that has more storage and compressing it prior to clearing it.
What is Wtmp in AIX?
/var/adm/wtmp on AIX maintains a list of past user sessions and information about the restart/shutdown of that particular system. While this file is normally very small in terms of file size, on an active box, this can grow if not properly maintained.