- Open Source, Freely available
- Released by Red Hat
- Fedora 4 and 5 include the original version of GFS, and Fedora Core 6 onwards includes GFS2 using a similar set of configuration and management tools and native kernel support for kernel-level operations.
GFS2 packages include:
- gfs2-utils: gfs2 service script to mount GFS2 file system to the location specified in the /etc/fstab file. Use the command
service gfs2 start
- cman: The Cluster Manager, to add or remove a node from a cluster. It runs as a kernel module directly. Use the below command to start file system service
service cman start
- lvm-cluster: The GFS configuration settings available in the /etc/sysconfig/cluster file
These packages contain tools like:
- fence: Fence overview
- fenced: Fencing daemon and a service script for starting the fenced daemon
- fence_tool: Manages the fenced daemon, to isolate failed resources, supported by the fence server
- fence_node: invokes fence agent
- fencing agents: Numerous fencing agents available for different kinds of connections
- fence_manual: Fence agent for manual interaction
- fence_ack_manual: User interface for fence_manual
- gulm_tool: manage gulm locking
- cman_tool: implements cluster management and manages cluster nodes
- dlm: The distributed lock manager managing locking control. It operates as a daemon with supporting libraries. It is implemented as kernel module invoked by the cman script.
- css cluster configuration supported by Cluster Configuration System. LVM cluster support locates in packages lvm2-cluster (Fedora) and clvm (Debian).
- ccs: CCS service script to start Cluster Configuration Service Server
- ccs_tool: CCS configuration update tool. To create cluster.ccs, fence,ccs and node.ccs configuration files, organized into CCS archive placed on each node and cluster device.
- css_test: CCS diagnostic tools to test CCS configuration files
- ccsd: Daemon run on nodes to provide CCS configuration data to cluster software
- clvmd: Cluster Logical Volume Manager daemon, needed to create and manage LVM cluster devices. It is also a script to start clvmd.
- cman script: Cluster Configuration System. It checks the /etc/cluster.conf file for cluster configuration and run ccsd to start up configuration.
- clusterfs: The primary administrative tool
- gfs2: To create a file system on the cluster device, use the command gfs2_mkfs, and mount them with the -t gfs2 option (-t indicates lock table)
- gfs2_mount: Use -t gfs2 mount option
mount -t gfs2 /dev/vg0/mgfs /anagfs
- gfs2_fsck: The GFS2 file system checker for corrupt system and attempting repairs. Unmount the file system before using gfs2_fsck.
- gfs2_grow: Grows a GFS2 file system to available space, from one node to expand the entire cluster
- gfs2_jadd: Adds a journal to a GFS 2 file system. Journal files are installed in space outside of the GFS file system.
- gfs2_quota: Manipulates GFS2 disk quotas
- gfs2_tool: Manages a GFS2 file system
- getfacl: Gets the ACL permission for a file or directory
- setfact: Set access control (ACL) for a file or directory, restrict users or groups, specifying read or write permissions. The -m option to modify and ACL permission and -x to delete it.
- mkfs-gfs2: Makes a GFS2 file system
- rmanager: Resource Group Manager, provides a command line interface for managing user services and resources on a GFS file system. It let user to perform basic administrative tasks like setting user quotas, shutting down the system (clushutdown), and statistics on GFS use (clustat).
Implement GFS2 File System
The GFS can run directly via connecting to SAN (storage area network) or GNBD (Global Network Block Device) storage connected over a LAN (Ethernet) -connected systems. It separates the physical implementation from the logical format.
To setup GFS2 file system, create a cluster device using the physical-volumes and organize them in logical-volumes. The GFS logical volumes created and managed by the Cluster Logical Volume Manager (CLVM), a cluster enabled LVM. They can easily mount on any directory on the Linux file system.
gfs2_mkfs -t ananovacluster:anagfs -p lock_dlm -j 2 /dev/vg0/mgfs mount -t gfs /dev/vg0/mgfs /gfs1
Place an entry in the /etc/fstab file to automatically mount file system
/dev/vg0/mgfs /anagfs gfs2 noauto,defaults 0 0 service gfs start