Simplify Log Parsing: Identifying Errors and IP Addresses

As a systems administrator, parsing log files is a common yet challenging task. Learn how to effectively parse an error log file from a website with over 1,500 lines of entries. Discover the use of tools like 'less' to navigate logs and 'grep' with regular expressions to filter specific error messages. Additionally, gain insights into sorting and identifying unique IP addresses to pinpoint potential issues or malicious activity. Enhance your log analysis skills with these practical techniques.

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Bash: Shortcuts and Scripting Tutorial for Linux | Into the Terminal 108

Linux File Permissions | Into the Terminal 105

Helpful Linux commands (Admin 101)

00:00 Introduction to Log Parsing
00:07 Exploring the Error Log
00:36 Using 'less' for Log Navigation
00:45 Identifying Common Errors
01:12 Extracting IP Addresses
01:53 Using Grep and Regex
03:01 Sorting and Filtering IP Addresses
03:49 Counting and Sorting IP Occurrences
04:46 Analyzing the Results

[bobanmilisavljevic]

Thanks for the reminder to review regular expressions

[brianshizniz]

That IP regex is neat! I guess you could then pipe those addresses into dig for rDNS maybe, perhaps with awk/sed/xargs? That would be neat. I’ve also always wondered about how to parse through dates and times for identifying patterns, but not sure where on bash or the cmd line one would do that…. 😅