ext2, ext3 and ext4 are all filesystems created for Linux. This article explains the following: High level difference between these filesystems. How to create these filesystems. How to convert from one filesystem type to another. Ext2 Ext2 stands for second extended file system. It was introduced in 1993. Developed by Rémy Card. This was developed [...]
Ramesh Natarajan
As we discussed in our Linux performance monitoring introduction article, measuring IO subsystem performance is very important. If someone is complaining that a database (or any application) running on one server (with certain filesystem, or RAID configuration) is running faster than the same database or application running on another server, you might want to make [...]
Question: How do I identify my file system type? I like to upgrade my current file system to the latest ext4. Before that I would like to know what my current file system type is for various mount points I have on my UNIX system. Answer: Use any one of the five methods mentioned below [...]
If you are spending lot of time on UNIX / Linux, you’ll be manipulating text files frequently. You may be making the similar edits on multiple configuration files on one or more servers. You may be digging huge log files (or data files) looking for certain information. Sed and Awk 101 Hacks is a downloadable [...]
Using sar you can monitor performance of various Linux subsystems (CPU, Memory, I/O..) in real time. Using sar, you can also collect all performance data on an on-going basis, store them, and do historical analysis to identify bottlenecks. Sar is part of the sysstat package. This article explains how to install and configure sysstat package [...]
For the past several months, I’ve been working on writing a book on the two great UNIX tools — Sed and Awk. I’ve spend lot of sleepless nights to make this book easy to read and understand with lot of examples. It is almost complete and the book will be released very soon. Once you [...]
If you are a sysadmin, you should secure your Apache web server by following the 10 tips mentioned in this article. 1. Disable unnecessary modules If you are planning to install apache from source, you should disable the following modules. If you do ./configure –help, you’ll see all available modules that you can disable/enable. userdir [...]
In our previous IPTables firewall series article, we reviewed how to add firewall rule using “iptables -A”. We also explained how to allow incoming SSH connection. On a high-level, it involves following 3 steps. Delete all existing rules: “iptables -F” Allow only incoming SSH: “iptables -A INPUT -i eth0 -p tcp –dport 22 -j ACCEPT” [...]