How to connect to Cisco routers using Minicom

In this tutorial, I am going to show you how to connect to a Cisco router by using Minicom terminal. I am using Linux by the way. If you’re
using Window$, besides the suggestion to dump it out and change it with Linux, I think hyperterminal is still your best option. Just Google it: “How to hyperterminal cisco router”. Continue reading

Understanding logrotate utility

Logs are useful when you want to track usage or troubleshoot an application. As more information gets logged, however, log files use more disk space. Over time a log file can grow to unwieldy size. Running out of disk space because of a large log file is a problem, but a large log file can also slow down the process of resizing or backing up your virtual server. Additionally, it’s hard to look for a particular event if you have a million log entries to skim through. So it’s a good idea to keep log files down to a manageable size, and to prune them when they get too old to be of much use. Continue reading

Linux audit files to see who made changes to a file

This is one of the key questions many new sys admin ask:

How do I audit file events such as read / write etc? How can I use audit to see who changed a file in Linux?

The answer is to use 2.6 kernel’s audit system. Modern Linux kernel (2.6.x) comes with auditd daemon. It’s responsible for writing audit records to the disk. During startup, the rules in /etc/audit.rules are read by this daemon. You can open /etc/audit.rules file and make changes such as setup audit file log location and other option. The default file is good enough to get started with auditd. Continue reading

Linux Troubleshooting – semanage command not found in CentOS 7/RHEL 7

How to check hard disk health on Linux using smartmontools

If there is something that you never want to happen on your Linux system, that is having hard drives die on you without any warning. Backups and storage technologies such as RAID can get you back on your feet in no time, but the cost associated with a sudden loss of a hardware device can take a considerable toll on your budget, especially if you haven’t planned ahead of time what to do in such circumstances. Continue reading