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Which command will provide you with a live watch of a log file?
I often need to watch a log file in live action, for error detection. The command tail -f will display the last 10 lines of a file, and then continuously wait for new lines, and display them as they appear. The tail command is fast and simple.
What does the command FIND do?
Find command is used to search and locate the list of files and directories based on conditions you specify for files that match the arguments. Find can be used in a variety of conditions like you can find files by permissions, users, groups, file type, date, size, and other possible criteria.
How to display a log file in real time?
As said, tail command is the most common solution to display a log file in real time. However, the command to display the file has two versions, as illustrated in the below examples. In the first example the command tail needs the -f argument to follow the content of a file. $ sudo tail -f /var/log/apache2/access.log
How to monitor any command output in real time?
Monitor log output One of the most common scenarios in Linux is looking at the log output of an application using the tail command $ tail -n 10 output.log This command will output the last 10 lines of the output.log file to the terminal console.
How to show the first 10 lines of a log file?
This example displays only first 15 lines of /var/log/maillog file. Change 15 to 10 to display the first 10 lines of a log file. This example shows how to ignore the last N lines, and show only the remaining lines from the top of file. The following example will display all the lines of the /var/log/secure except the last 250 lines.
How can I watch a log file rotate?
To watch log files that get rotated on a daily base you can use the -F flag to tail command. The tail -F will keep track if new log file being created and will start following the new file instead of the old file. However, by default, tail command will display the last 10 lines of a file.