mount forcedirectio: Disable Linux CIFS / NFS Client Caching

Posted on in Categories CentOS, File system, GNU/Open source, kernel, Linux, Linux Scalability, RedHat/Fedora Linux, Storage, UNIX last updated November 16, 2008

If your network is heavily loaded you may see some problem with Common Internet File System (CIFS) and NFS under Linux. By default Linux CIFS mount command will try to cache files open by the client. You can use mount option forcedirectio when mounting the CIFS filesystem to disable caching on the CIFS client. This is tested with NETAPP and other storage devices and Novell, CentOS, UNIX and Red Hat Linux systems. This is the only way to avoid data mis-compare and problems.

Linux Supports More Devices Than Any Other OS

Posted on in Categories GNU/Open source, Hardware, kernel, Linux, News last updated November 3, 2008

Interesting read and claim has been independently verified by somebody from Microsoft.

Greg Kroah-Hartman is a longtime developer of the Linux kernel, known for his work maintaining USB drivers as well as for packaging the SUSE kernel at Novell. O’Reilly Media recently interviewed Greg about his claim that the Linux kernel now supports more devices than any other operating system ever has, as well as why binary-only drivers are illegal, and how the kernel development process works.

Read full interview: How Linux Supports More Devices Than Any Other OS, Ever

Troubleshooting Lighttpd Chrooted RedHat PHP Version 5.1.6-20.el5_2.1

Posted on in Categories CentOS, GNU/Open source, kernel, lighttpd, Linux, Linux distribution, php, RedHat/Fedora Linux, Troubleshooting last updated October 1, 2008

It appears that latest php version 5.1.6-20.el5_2.1 under RHEL / CentOS Linux v5.2 has made some major changes. As a result choort jail setup using previous instructions no longer works. PHP is crashing with segmentation fault errors. So I had to trace php errors using strace command.