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.

How To Track Changes in Your Linux Filesystem

Posted on in Categories File system, Howto, Linux, RedHat/Fedora Linux, Sys admin, Tips last updated January 25, 2008

kfsmd is an interesting tool to keep track of changes in your filesystems. This tool based upon inotify which is a Linux kernel subsystem that provides file system event notification. Useful for file auditing. From the article:

Applications can ask the Linux kernel to report changes to selected files and directories. I created the Kernel Filesystem Monitoring Daemon (kfsmd) to make monitoring filesystem changes simple. Command-line clients for kfsmd come in two categories: monitoring and logging. The monitoring client produces output on the console whenever something happens to a filesystem you are watching. You can log to either a Berkeley DB4 file or a PostgreSQL database.

=> Use kfsmd to keep track of changes in your filesystems

Related: Linux audit files to see who made changes to a file