#grep command

See, that is why Redhat and Mr. Poettering have introduced all in one systemd command that does grep command and limiting output in a single go for a given service log. How cool is that? You guys hate systemd for no good reason 🤭

journalctl -u nginx.service -g failed -n 10

UNIX Grep command examples

Hi Friends, today we will see some use of UNIX GREP command examples which is very useful and powerful command. As we all know that grep command is used mainly for pattern search in files. But this is just the basic explanation of grep command. Today we will see how grep is enriched with a lot of options to do pattern search in many other ways.

Let’s consider below example file on which we…

Filter Logs with Grep : linux Command Grep

Filter Logs with Grep : linux Command Grep

Let’s understand the use of grep is to extract useful information from system logs:

grep -Eoc "^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}.* 200" /srv/www/example.com/logs/access.log

  In this command, grep filters an Apache access log for all lines that begin with an IP address, followed by a number of characters, a space and then the characters