Linux Convert ext3 to ext4 File system

Posted on in Categories CentOS, Data recovery, Linux, Linux desktop, Linux distribution, RedHat/Fedora Linux, Storage, Suse Linux, Sys admin, Tips, Troubleshooting, Tuning, Ubuntu Linux last updated January 23, 2009

Some time ago ext4 was released and available for Linux kernel. ext4 provides some additional benefits and perforce over ext3 file system. You can easily convert ext3 to ext4 file system. The next release of Fedora, 11, will default to the ext4 file system unless serious regressions are seen. In this quick tutorial you will learn about converting ext3 to ext4 file system.

How To Measure Linux Filesystem I/O Performance With iozone

Posted on in Categories File system, High performance computing, Linux, Linux distribution, RedHat/Fedora Linux, Storage, Sys admin, Tips, UNIX last updated July 4, 2008

IOzone is a filesystem benchmark tool. The benchmark generates and measures a variety of file operations. Iozone has been ported to many systems and runs under many operating systems including Windows, UNIX, Linux and BSD. This article gives you a jumpstart on performing benchmark on filesystem using iozone a free Filesystem Benchmark utility under Linux.

Mount a Linux filesystem on a SAN from multiple nodes at the same time

Posted on in Categories CentOS, FAQ, File system, Gentoo Linux, Hardware, High performance computing, Linux, Linux Scalability, RedHat/Fedora Linux, Storage last updated May 12, 2006

If you try to mount an ext3 Linux filesystem on a SAN from multiple nodes at the same time you will be in serious deep trouble.

SAN based storage allows multiple nodes to connect to same devices at the same time. Ext3/2 are not cluster aware file system. They can lead to a disaster such as kernel panic, server hang, corruption etc.

You need to use something which supports:

  1. Useful in clusters for moderate scale out and shared SAN volumes
  2. Symmetrical Parallel Cluster File System, Journaled
  3. POSIX access controls

Both GFS (RedHat Global File System) and Lustre (a scalable, secure, robust, highly available cluster file system) can be used with SAN based storage allows multiple nodes to connect to same devices at the same time.

Many newbie get confused as Linux offers a number of file systems. This paper (Linux File System Primer) discusses these file systems, why there are so many, and which ones are the best to use for which workloads and data.