How To: Upgrade Red Hat Enterprise Linux 5.3 to v5.4

Posted on in Categories GNU/Open source, Hardware, Howto, Linux, Linux distribution, News, package management, RedHat/Fedora Linux last updated September 2, 2009

Red Hat Enterprise Linux v5.4 has been released and available via RHN for immediate update. The new version includes the kernel-based virtual machine (KVM) virtualization, next generation of developer features and tools including GCC 4.4, a new malloc(). Also included clustered, high-availability filesystem to support Microsoft Windows storage needs on Red Hat Enterprise Linux.

Install Linux On Intel Xeon 7400 Dunnington

Posted on in Categories Hardware, Links, Linux, Linux distribution, Linux Scalability, Linux Virtualization, vmware last updated November 13, 2008

Dunnington is Intel’s first multi-core CPU – features a single-die six- (or hexa) core design with three unified 3 MB L2 caches (resembling three merged 45 nm dual-core Wolfdale dies), and 96 KB L1 cache (Data) and 16 MB of L3 cache. It features 1066 MHz FSB, fits into the Tigerton’s mPGA604 socket, and is compatible with the Caneland chipset. These processors support DDR2-1066 (533 MHz), and have a maximum TDP below 130 W. They are intended for blades and other stacked computer systems.

CentOS / Red Hat Enterprise Linux 5.2 Poor NFS Performance and Solution

Posted on in Categories Apache, CentOS, data center, File system, High performance computing, Howto, Linux, Linux distribution, Networking, package management, RedHat/Fedora Linux, Security Alert, Storage, Sys admin, Troubleshooting, Tuning last updated August 22, 2008

A few days ago I noticed that NFS performance between a web server node and NFS server went down by 50%. NFS was optimized and the only thing was updated Red Hat kernel v5.2. I also noticed same trend on CentOS 5.2 64 bit edition.

dnsmasq Dns Cache Software Security Update To Fix DNS Spoofing Attacks

Posted on in Categories BIND Dns, CentOS, Debian Linux, fedora linux, Linux, Linux distribution, package management, RedHat/Fedora Linux, Security Alert last updated August 12, 2008

Red Hat has shipped a new version of its dnsmasq caching software to plug source UDP port bug. This could have made DNS spoofing attacks (CVE-2008-1447) easier. Dnsmasq is lightweight ultra fast dns cache server forwarder and DHCP server. It is designed to provide DNS and, optionally, DHCP, to a small network.

How To: Double Linux disk read performance with readahead parameter

Posted on in Categories CentOS, Debian Linux, File system, Hardware, Howto, Linux, RedHat/Fedora Linux, Storage, Suse Linux, Tuning last updated November 22, 2007

The open source journal has published an interesting hack. It mostly applies to high-end, multiple-disk storage:

Under the right conditions (that is, with certain hardware configurations which I’ll identify later) it is possible to literally double your sequential read performance from disk. If you noticed the terrible performance of the 3Ware 9500S RAID controller and cared enough to investigate. It all has to do with a sneaky little block device parameter known as readahead. Without going into too much gory detail, readahead controls how much in advance the operating system reads when, well, reading, as its name implies. By default, some operating systems (in particular, RHEL5 Server) sets this to 256 (512-byte sectors), or about 128 KB. When dealing with large filesystems spanning many disks, this paltry figure can actually nuke your performance.

=> HowTo: Linux: Double your disk read performance in a single command